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// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2015 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or
#include "addrdb.h"
#include "addrman.h"
#include "amount.h"
#include "bloom.h"
#include "compat.h"
#include "hash.h"
#include "limitedmap.h"
#include "netaddress.h"
#include "protocol.h"
#include "random.h"
#include "streams.h"
#include "sync.h"
#include "uint256.h"
#include "threadinterrupt.h"
#include <atomic>
#include <deque>
#include <stdint.h>
#include <thread>
#include <memory>
#include <condition_variable>
#ifndef WIN32
#include <arpa/inet.h>
#include <boost/filesystem/path.hpp>
#include <boost/foreach.hpp>
#include <boost/signals2/signal.hpp>
class CAddrMan;
class CScheduler;
class CNode;
namespace boost {
class thread_group;
} // namespace boost
/** Time between pings automatically sent out for latency probing and keepalive (in seconds). */
static const int PING_INTERVAL = 2 * 60;
/** Time after which to disconnect, after waiting for a ping response (or inactivity). */
static const int TIMEOUT_INTERVAL = 20 * 60;
/** Run the feeler connection loop once every 2 minutes or 120 seconds. **/
static const int FEELER_INTERVAL = 120;
/** The maximum number of entries in an 'inv' protocol message */
static const unsigned int MAX_INV_SZ = 50000;
/** The maximum number of new addresses to accumulate before announcing. */
static const unsigned int MAX_ADDR_TO_SEND = 1000;
/** Maximum length of incoming protocol messages (no message over 4 MB is currently acceptable). */
static const unsigned int MAX_PROTOCOL_MESSAGE_LENGTH = 4 * 1000 * 1000;
/** Maximum length of strSubVer in `version` message */
static const unsigned int MAX_SUBVERSION_LENGTH = 256;
/** Maximum number of outgoing nodes */
static const int MAX_OUTBOUND_CONNECTIONS = 8;
/** -listen default */
static const bool DEFAULT_LISTEN = true;
/** -upnp default */
#ifdef USE_UPNP
static const bool DEFAULT_UPNP = USE_UPNP;
static const bool DEFAULT_UPNP = false;
/** The maximum number of entries in mapAskFor */
static const size_t MAPASKFOR_MAX_SZ = MAX_INV_SZ;
/** The maximum number of entries in setAskFor (larger due to getdata latency)*/
static const size_t SETASKFOR_MAX_SZ = 2 * MAX_INV_SZ;
/** The maximum number of peer connections to maintain. */
static const unsigned int DEFAULT_MAX_PEER_CONNECTIONS = 125;
/** The default for -maxuploadtarget. 0 = Unlimited */
static const uint64_t DEFAULT_MAX_UPLOAD_TARGET = 0;
/** The default timeframe for -maxuploadtarget. 1 day. */
static const uint64_t MAX_UPLOAD_TIMEFRAME = 60 * 60 * 24;
/** Default for blocks only*/
static const bool DEFAULT_BLOCKSONLY = false;
static const bool DEFAULT_FORCEDNSSEED = false;
static const size_t DEFAULT_MAXRECEIVEBUFFER = 5 * 1000;
static const size_t DEFAULT_MAXSENDBUFFER = 1 * 1000;
static const ServiceFlags REQUIRED_SERVICES = NODE_NETWORK;
// NOTE: When adjusting this, update rpcnet:setban's help ("24h")
static const unsigned int DEFAULT_MISBEHAVING_BANTIME = 60 * 60 * 24; // Default 24-hour ban
typedef int NodeId;
struct AddedNodeInfo
std::string strAddedNode;
CService resolvedAddress;
bool fConnected;
bool fInbound;
class CTransaction;
class CNodeStats;
class CClientUIInterface;
struct CSerializedNetMsg
CSerializedNetMsg() = default;
CSerializedNetMsg(CSerializedNetMsg&&) = default;
CSerializedNetMsg& operator=(CSerializedNetMsg&&) = default;
// No copying, only moves.
CSerializedNetMsg(const CSerializedNetMsg& msg) = delete;
CSerializedNetMsg& operator=(const CSerializedNetMsg&) = delete;
std::vector<unsigned char> data;
std::string command;
class CConnman
enum NumConnections {
struct Options
ServiceFlags nLocalServices = NODE_NONE;
ServiceFlags nRelevantServices = NODE_NONE;
int nMaxConnections = 0;
int nMaxOutbound = 0;
int nMaxFeeler = 0;
int nBestHeight = 0;
CClientUIInterface* uiInterface = nullptr;
unsigned int nSendBufferMaxSize = 0;
unsigned int nReceiveFloodSize = 0;
uint64_t nMaxOutboundTimeframe = 0;
uint64_t nMaxOutboundLimit = 0;
CConnman(uint64_t seed0, uint64_t seed1);
bool Start(CScheduler& scheduler, std::string& strNodeError, Options options);
void Stop();
void Interrupt();
bool BindListenPort(const CService &bindAddr, std::string& strError, bool fWhitelisted = false);
bool GetNetworkActive() const { return fNetworkActive; };
void SetNetworkActive(bool active);
bool OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound = NULL, const char *strDest = NULL, bool fOneShot = false, bool fFeeler = false);
bool CheckIncomingNonce(uint64_t nonce);
bool ForNode(NodeId id, std::function<bool(CNode* pnode)> func);
void PushMessage(CNode* pnode, CSerializedNetMsg&& msg);
template<typename Callable>
bool ForEachNodeContinueIf(Callable&& func)
for (auto&& node : vNodes)
return false;
return true;
template<typename Callable>
bool ForEachNodeContinueIf(Callable&& func) const
for (const auto& node : vNodes)
return false;
return true;
template<typename Callable, typename CallableAfter>
bool ForEachNodeContinueIfThen(Callable&& pre, CallableAfter&& post)
bool ret = true;
for (auto&& node : vNodes)
if(!pre(node)) {
ret = false;
return ret;
template<typename Callable, typename CallableAfter>
bool ForEachNodeContinueIfThen(Callable&& pre, CallableAfter&& post) const
bool ret = true;
for (const auto& node : vNodes)
if(!pre(node)) {
ret = false;
return ret;
template<typename Callable>
void ForEachNode(Callable&& func)
for (auto&& node : vNodes)
template<typename Callable>
void ForEachNode(Callable&& func) const
for (const auto& node : vNodes)
template<typename Callable, typename CallableAfter>
void ForEachNodeThen(Callable&& pre, CallableAfter&& post)
for (auto&& node : vNodes)
template<typename Callable, typename CallableAfter>
void ForEachNodeThen(Callable&& pre, CallableAfter&& post) const
for (const auto& node : vNodes)
void RelayTransaction(const CTransaction& tx);
// Addrman functions
size_t GetAddressCount() const;
void SetServices(const CService &addr, ServiceFlags nServices);
void MarkAddressGood(const CAddress& addr);
void AddNewAddress(const CAddress& addr, const CAddress& addrFrom, int64_t nTimePenalty = 0);
void AddNewAddresses(const std::vector<CAddress>& vAddr, const CAddress& addrFrom, int64_t nTimePenalty = 0);
std::vector<CAddress> GetAddresses();
void AddressCurrentlyConnected(const CService& addr);
// Denial-of-service detection/prevention
// The idea is to detect peers that are behaving
// badly and disconnect/ban them, but do it in a
// one-coding-mistake-won't-shatter-the-entire-network
// way.
// IMPORTANT: There should be nothing I can give a
// node that it will forward on that will make that
// node's peers drop it. If there is, an attacker
// can isolate a node and/or try to split the network.
// Dropping a node for sending stuff that is invalid
// now but might be valid in a later version is also
// dangerous, because it can cause a network split
// between nodes running old code and nodes running
// new code.
void Ban(const CNetAddr& netAddr, const BanReason& reason, int64_t bantimeoffset = 0, bool sinceUnixEpoch = false);
void Ban(const CSubNet& subNet, const BanReason& reason, int64_t bantimeoffset = 0, bool sinceUnixEpoch = false);
void ClearBanned(); // needed for unit testing
bool IsBanned(CNetAddr ip);
bool IsBanned(CSubNet subnet);
bool Unban(const CNetAddr &ip);
bool Unban(const CSubNet &ip);
void GetBanned(banmap_t &banmap);
void SetBanned(const banmap_t &banmap);
void AddOneShot(const std::string& strDest);
bool AddNode(const std::string& node);
bool RemoveAddedNode(const std::string& node);
std::vector<AddedNodeInfo> GetAddedNodeInfo();
size_t GetNodeCount(NumConnections num);
void GetNodeStats(std::vector<CNodeStats>& vstats);
bool DisconnectAddress(const CNetAddr& addr);
bool DisconnectNode(const std::string& node);
bool DisconnectNode(NodeId id);
bool DisconnectSubnet(const CSubNet& subnet);
unsigned int GetSendBufferSize() const;
void AddWhitelistedRange(const CSubNet &subnet);
ServiceFlags GetLocalServices() const;
//!set the max outbound target in bytes
void SetMaxOutboundTarget(uint64_t limit);
uint64_t GetMaxOutboundTarget();
//!set the timeframe for the max outbound target
void SetMaxOutboundTimeframe(uint64_t timeframe);
uint64_t GetMaxOutboundTimeframe();
//!check if the outbound target is reached
// if param historicalBlockServingLimit is set true, the function will
// response true if the limit for serving historical blocks has been reached
bool OutboundTargetReached(bool historicalBlockServingLimit);
//!response the bytes left in the current max outbound cycle
// in case of no limit, it will always response 0
uint64_t GetOutboundTargetBytesLeft();
//!response the time in second left in the current max outbound cycle
// in case of no limit, it will always response 0
uint64_t GetMaxOutboundTimeLeftInCycle();
uint64_t GetTotalBytesRecv();
uint64_t GetTotalBytesSent();
void SetBestHeight(int height);
int GetBestHeight() const;
/** Get a unique deterministic randomizer. */
CSipHasher GetDeterministicRandomizer(uint64_t id);
struct ListenSocket {
SOCKET socket;
bool whitelisted;
ListenSocket(SOCKET socket_, bool whitelisted_) : socket(socket_), whitelisted(whitelisted_) {}
void ThreadOpenAddedConnections();
void ProcessOneShot();
void ThreadOpenConnections();
void ThreadMessageHandler();
void AcceptConnection(const ListenSocket& hListenSocket);
void ThreadSocketHandler();
void ThreadDNSAddressSeed();
uint64_t CalculateKeyedNetGroup(const CAddress& ad);
CNode* FindNode(const CNetAddr& ip);
CNode* FindNode(const CSubNet& subNet);
CNode* FindNode(const std::string& addrName);
CNode* FindNode(const CService& addr);
bool AttemptToEvictConnection();
CNode* ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure);
bool IsWhitelistedRange(const CNetAddr &addr);
void DeleteNode(CNode* pnode);
NodeId GetNewNodeId();
//!check is the banlist has unwritten changes
bool BannedSetIsDirty();
//!set the "dirty" flag for the banlist
void SetBannedSetDirty(bool dirty=true);
//!clean unused entries (if bantime has expired)
void SweepBanned();
void DumpAddresses();
void DumpData();
void DumpBanlist();
unsigned int GetReceiveFloodSize() const;
// Network stats
void RecordBytesRecv(uint64_t bytes);
void RecordBytesSent(uint64_t bytes);
// Network usage totals
CCriticalSection cs_totalBytesRecv;
CCriticalSection cs_totalBytesSent;
uint64_t nTotalBytesRecv;
uint64_t nTotalBytesSent;
// outbound limit & stats
uint64_t nMaxOutboundTotalBytesSentInCycle;
uint64_t nMaxOutboundCycleStartTime;
uint64_t nMaxOutboundLimit;
uint64_t nMaxOutboundTimeframe;
// Whitelisted ranges. Any node connecting from these is automatically
// whitelisted (as well as those connecting to whitelisted binds).
std::vector<CSubNet> vWhitelistedRange;
CCriticalSection cs_vWhitelistedRange;
unsigned int nSendBufferMaxSize;
unsigned int nReceiveFloodSize;
std::vector<ListenSocket> vhListenSocket;
std::atomic<bool> fNetworkActive;
banmap_t setBanned;
CCriticalSection cs_setBanned;
bool setBannedIsDirty;
bool fAddressesInitialized;
CAddrMan addrman;
std::deque<std::string> vOneShots;
CCriticalSection cs_vOneShots;
std::vector<std::string> vAddedNodes;
CCriticalSection cs_vAddedNodes;
std::vector<CNode*> vNodes;
std::list<CNode*> vNodesDisconnected;
mutable CCriticalSection cs_vNodes;
std::atomic<NodeId> nLastNodeId;
/** Services this instance offers */
ServiceFlags nLocalServices;
/** Services this instance cares about */
ServiceFlags nRelevantServices;
CSemaphore *semOutbound;
int nMaxConnections;
int nMaxOutbound;
int nMaxFeeler;
std::atomic<int> nBestHeight;
CClientUIInterface* clientInterface;
/** SipHasher seeds for deterministic randomness */
const uint64_t nSeed0, nSeed1;
std::condition_variable condMsgProc;
std::mutex mutexMsgProc;
std::atomic<bool> flagInterruptMsgProc;
CThreadInterrupt interruptNet;
std::thread threadDNSAddressSeed;
std::thread threadSocketHandler;
std::thread threadOpenAddedConnections;
std::thread threadOpenConnections;
std::thread threadMessageHandler;
extern std::unique_ptr<CConnman> g_connman;
void Discover(boost::thread_group& threadGroup);
void MapPort(bool fUseUPnP);
unsigned short GetListenPort();
bool BindListenPort(const CService &bindAddr, std::string& strError, bool fWhitelisted = false);
size_t SocketSendData(CNode *pnode);
struct CombinerAll
typedef bool result_type;
template<typename I>
bool operator()(I first, I last) const
while (first != last) {
if (!(*first)) return false;
return true;
// Signals for message handling
struct CNodeSignals
boost::signals2::signal<bool (CNode*, CConnman&, std::atomic<bool>&), CombinerAll> ProcessMessages;
boost::signals2::signal<bool (CNode*, CConnman&, std::atomic<bool>&), CombinerAll> SendMessages;
boost::signals2::signal<void (CNode*, CConnman&)> InitializeNode;
boost::signals2::signal<void (NodeId, bool&)> FinalizeNode;
CNodeSignals& GetNodeSignals();
LOCAL_NONE, // unknown
LOCAL_IF, // address a local interface listens on
LOCAL_BIND, // address explicit bound to
LOCAL_UPNP, // address reported by UPnP
LOCAL_MANUAL, // address explicitly specified (-externalip=)
bool IsPeerAddrLocalGood(CNode *pnode);
void AdvertiseLocal(CNode *pnode);
void SetLimited(enum Network net, bool fLimited = true);
bool IsLimited(enum Network net);
bool IsLimited(const CNetAddr& addr);
bool AddLocal(const CService& addr, int nScore = LOCAL_NONE);
bool AddLocal(const CNetAddr& addr, int nScore = LOCAL_NONE);
bool RemoveLocal(const CService& addr);
bool SeenLocal(const CService& addr);
bool IsLocal(const CService& addr);
bool GetLocal(CService &addr, const CNetAddr *paddrPeer = NULL);
bool IsReachable(enum Network net);
bool IsReachable(const CNetAddr &addr);
CAddress GetLocalAddress(const CNetAddr *paddrPeer, ServiceFlags nLocalServices);
extern bool fDiscover;
extern bool fListen;
extern bool fRelayTxes;
extern limitedmap<uint256, int64_t> mapAlreadyAskedFor;
/** Subversion as sent to the P2P network in `version` messages */
extern std::string strSubVersion;
struct LocalServiceInfo {
int nScore;
int nPort;
extern CCriticalSection cs_mapLocalHost;
extern std::map<CNetAddr, LocalServiceInfo> mapLocalHost;
typedef std::map<std::string, uint64_t> mapMsgCmdSize; //command, total bytes
class CNodeStats
NodeId nodeid;
ServiceFlags nServices;
bool fRelayTxes;
int64_t nLastSend;
int64_t nLastRecv;
int64_t nTimeConnected;
int64_t nTimeOffset;
std::string addrName;
int nVersion;
std::string cleanSubVer;
bool fInbound;
int nStartingHeight;
uint64_t nSendBytes;
mapMsgCmdSize mapSendBytesPerMsgCmd;
uint64_t nRecvBytes;
mapMsgCmdSize mapRecvBytesPerMsgCmd;
bool fWhitelisted;
double dPingTime;
double dPingWait;
double dMinPing;
std::string addrLocal;
CAddress addr;
class CNetMessage {
mutable CHash256 hasher;
mutable uint256 data_hash;
bool in_data; // parsing header (false) or data (true)
CDataStream hdrbuf; // partially received header
CMessageHeader hdr; // complete header
unsigned int nHdrPos;
CDataStream vRecv; // received message data
unsigned int nDataPos;
int64_t nTime; // time (in microseconds) of message receipt.
CNetMessage(const CMessageHeader::MessageStartChars& pchMessageStartIn, int nTypeIn, int nVersionIn) : hdrbuf(nTypeIn, nVersionIn), hdr(pchMessageStartIn), vRecv(nTypeIn, nVersionIn) {
in_data = false;
nHdrPos = 0;
nDataPos = 0;
nTime = 0;
bool complete() const
if (!in_data)
return false;
return (hdr.nMessageSize == nDataPos);
const uint256& GetMessageHash() const;
void SetVersion(int nVersionIn)
int readHeader(const char *pch, unsigned int nBytes);
int readData(const char *pch, unsigned int nBytes);
/** Information about a peer */
class CNode
friend class CConnman;
// socket
ServiceFlags nServices;
ServiceFlags nServicesExpected;
SOCKET hSocket;
size_t nSendSize; // total size of all vSendMsg entries
size_t nSendOffset; // offset inside the first vSendMsg already sent
uint64_t nSendBytes;
std::deque<std::vector<unsigned char>> vSendMsg;
CCriticalSection cs_vSend;
std::deque<CInv> vRecvGetData;
std::deque<CNetMessage> vRecvMsg;
CCriticalSection cs_vRecvMsg;
uint64_t nRecvBytes;
int nRecvVersion;
int64_t nLastSend;
int64_t nLastRecv;
int64_t nTimeConnected;
int64_t nTimeOffset;
const CAddress addr;
std::string addrName;
CService addrLocal;
int nVersion;
// strSubVer is whatever byte array we read from the wire. However, this field is intended
// to be printed out, displayed to humans in various forms and so on. So we sanitize it and
// store the sanitized version in cleanSubVer. The original should be used when dealing with
// the network or wire types and the cleaned string used when displayed or logged.
std::string strSubVer, cleanSubVer;
bool fWhitelisted; // This peer can bypass DoS banning.
bool fFeeler; // If true this node is being used as a short lived feeler.
bool fOneShot;
bool fClient;
const bool fInbound;
bool fSuccessfullyConnected;
std::atomic_bool fDisconnect;
// We use fRelayTxes for two purposes -
// a) it allows us to not relay tx invs before receiving the peer's version message
// b) the peer may tell us in its version message that we should not relay tx invs
// unless it loads a bloom filter.
bool fRelayTxes; //protected by cs_filter
bool fSentAddr;
CSemaphoreGrant grantOutbound;
CCriticalSection cs_filter;
CBloomFilter* pfilter;
int nRefCount;
const NodeId id;
const uint64_t nKeyedNetGroup;
mapMsgCmdSize mapSendBytesPerMsgCmd;
mapMsgCmdSize mapRecvBytesPerMsgCmd;
uint256 hashContinue;
int nStartingHeight;
// flood relay
std::vector<CAddress> vAddrToSend;
CRollingBloomFilter addrKnown;
bool fGetAddr;
std::set<uint256> setKnown;
int64_t nNextAddrSend;
int64_t nNextLocalAddrSend;
// inventory based relay
CRollingBloomFilter filterInventoryKnown;
// Set of transaction ids we still have to announce.
// They are sorted by the mempool before relay, so the order is not important.
std::set<uint256> setInventoryTxToSend;
// List of block ids we still have announce.
// There is no final sorting before sending, as they are always sent immediately
// and in the order requested.
std::vector<uint256> vInventoryBlockToSend;
CCriticalSection cs_inventory;
std::set<uint256> setAskFor;
std::multimap<int64_t, CInv> mapAskFor;
int64_t nNextInvSend;
// Used for headers announcements - unfiltered blocks to relay
// Also protected by cs_inventory
std::vector<uint256> vBlockHashesToAnnounce;
// Used for BIP35 mempool sending, also protected by cs_inventory
bool fSendMempool;
// Last time a "MEMPOOL" request was serviced.
std::atomic<int64_t> timeLastMempoolReq;
// Block and TXN accept times
std::atomic<int64_t> nLastBlockTime;
std::atomic<int64_t> nLastTXTime;
// Ping time measurement:
// The pong reply we're expecting, or 0 if no pong expected.
uint64_t nPingNonceSent;
// Time (in usec) the last ping was sent, or 0 if no ping was ever sent.
int64_t nPingUsecStart;
// Last measured round-trip time.
int64_t nPingUsecTime;
// Best measured round-trip time.
int64_t nMinPingUsecTime;
// Whether a ping is requested.
bool fPingQueued;
// Minimum fee rate with which to filter inv's to this node
CAmount minFeeFilter;
CCriticalSection cs_feeFilter;
CAmount lastSentFeeFilter;
int64_t nextSendTimeFeeFilter;
CNode(NodeId id, ServiceFlags nLocalServicesIn, int nMyStartingHeightIn, SOCKET hSocketIn, const CAddress &addrIn, uint64_t nKeyedNetGroupIn, uint64_t nLocalHostNonceIn, const std::string &addrNameIn = "", bool fInboundIn = false);
CNode(const CNode&);
void operator=(const CNode&);
const uint64_t nLocalHostNonce;
// Services offered to this peer
const ServiceFlags nLocalServices;
const int nMyStartingHeight;
int nSendVersion;
NodeId GetId() const {
return id;
uint64_t GetLocalNonce() const {
return nLocalHostNonce;
int GetMyStartingHeight() const {
return nMyStartingHeight;
int GetRefCount()
assert(nRefCount >= 0);
return nRefCount;
// requires LOCK(cs_vRecvMsg)
unsigned int GetTotalRecvSize()
unsigned int total = 0;
BOOST_FOREACH(const CNetMessage &msg, vRecvMsg)
total += msg.vRecv.size() + 24;
return total;
// requires LOCK(cs_vRecvMsg)
bool ReceiveMsgBytes(const char *pch, unsigned int nBytes, bool& complete);
// requires LOCK(cs_vRecvMsg)
void SetRecvVersion(int nVersionIn)
nRecvVersion = nVersionIn;
BOOST_FOREACH(CNetMessage &msg, vRecvMsg)
void SetSendVersion(int nVersionIn)
// Send version may only be changed in the version message, and
// only one version message is allowed per session. We can therefore
// treat this value as const and even atomic as long as it's only used
// once the handshake is complete. Any attempt to set this twice is an
// error.
assert(nSendVersion == 0);
nSendVersion = nVersionIn;
int GetSendVersion() const
// The send version should always be explicitly set to
// INIT_PROTO_VERSION rather than using this value until the handshake
// is complete.
assert(nSendVersion != 0);
return nSendVersion;
CNode* AddRef()
return this;
void Release()
void AddAddressKnown(const CAddress& _addr)
void PushAddress(const CAddress& _addr, FastRandomContext &insecure_rand)
// Known checking here is only to save space from duplicates.
// SendMessages will filter it again for knowns that were added
// after addresses were pushed.
if (_addr.IsValid() && !addrKnown.contains(_addr.GetKey())) {
if (vAddrToSend.size() >= MAX_ADDR_TO_SEND) {
vAddrToSend[insecure_rand.rand32() % vAddrToSend.size()] = _addr;
} else {
void AddInventoryKnown(const CInv& inv)
void PushInventory(const CInv& inv)
if (inv.type == MSG_TX) {
if (!filterInventoryKnown.contains(inv.hash)) {
} else if (inv.type == MSG_BLOCK) {
void PushBlockHash(const uint256 &hash)
void AskFor(const CInv& inv);
void CloseSocketDisconnect();
void copyStats(CNodeStats &stats);
ServiceFlags GetLocalServices() const
return nLocalServices;
/** Return a timestamp in the future (in microseconds) for exponentially distributed events. */
int64_t PoissonNextSend(int64_t nNow, int average_interval_seconds);
#endif // BITCOIN_NET_H