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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 http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_NET_H
#define BITCOIN_NET_H
#include "addrdb.h"
#include "amount.h"
#include "bloom.h"
#include "compat.h"
#include "limitedmap.h"
#include "netaddress.h"
#include "protocol.h"
#include "random.h"
#include "streams.h"
#include "sync.h"
#include "uint256.h"
#include <atomic>
#include <deque>
#include <stdint.h>
#include <memory>
#ifndef WIN32
#include <arpa/inet.h>
#endif
#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;
/** -listen default */
static const bool DEFAULT_LISTEN = true;
/** -upnp default */
#ifdef USE_UPNP
static const bool DEFAULT_UPNP = USE_UPNP;
#else
static const bool DEFAULT_UPNP = false;
#endif
/** 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;
/** 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
unsigned int ReceiveFloodSize();
unsigned int SendBufferSize();
typedef int NodeId;
void AddOneShot(const std::string& strDest);
void AddressCurrentlyConnected(const CService& addr);
CNode* FindNode(const CNetAddr& ip);
CNode* FindNode(const CSubNet& subNet);
CNode* FindNode(const std::string& addrName);
CNode* FindNode(const CService& ip);
CNode* FindNode(const NodeId id); //TODO: Remove this
class CConnman
{
public:
CConnman();
~CConnman();
bool Start(boost::thread_group& threadGroup, std::string& strNodeError);
void Stop();
bool BindListenPort(const CService &bindAddr, std::string& strError, bool fWhitelisted = false);
bool OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound = NULL, const char *strDest = NULL, bool fOneShot = false, bool fFeeler = false);
private:
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();
CNode* ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure);
void DeleteNode(CNode* pnode);
std::vector<ListenSocket> vhListenSocket;
};
extern std::unique_ptr<CConnman> g_connman;
void MapPort(bool fUseUPnP);
unsigned short GetListenPort();
bool BindListenPort(const CService &bindAddr, std::string& strError, bool fWhitelisted = false);
bool StartNode(CConnman& connman, boost::thread_group& threadGroup, CScheduler& scheduler, std::string& strNodeError);
bool StopNode(CConnman& connman);
void 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;
++first;
}
return true;
}
};
// Signals for message handling
struct CNodeSignals
{
boost::signals2::signal<int ()> GetHeight;
boost::signals2::signal<bool (CNode*, CConnman&), CombinerAll> ProcessMessages;
boost::signals2::signal<bool (CNode*, CConnman&), CombinerAll> SendMessages;
boost::signals2::signal<void (NodeId, const CNode*)> InitializeNode;
boost::signals2::signal<void (NodeId, bool&)> FinalizeNode;
};
CNodeSignals& GetNodeSignals();
enum
{
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=)
LOCAL_MAX
};
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 = NULL);
extern bool fDiscover;
extern bool fListen;
extern ServiceFlags nLocalServices;
extern ServiceFlags nRelevantServices;
extern bool fRelayTxes;
extern uint64_t nLocalHostNonce;
extern CAddrMan addrman;
/** Maximum number of connections to simultaneously allow (aka connection slots) */
extern int nMaxConnections;
extern std::vector<CNode*> vNodes;
extern CCriticalSection cs_vNodes;
extern limitedmap<uint256, int64_t> mapAlreadyAskedFor;
extern std::vector<std::string> vAddedNodes;
extern CCriticalSection cs_vAddedNodes;
extern NodeId nLastNodeId;
extern CCriticalSection cs_nLastNodeId;
/** 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
{
public:
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 dPingMin;
std::string addrLocal;
};
class CNetMessage {
public:
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) {
hdrbuf.resize(24);
in_data = false;
nHdrPos = 0;
nDataPos = 0;
nTime = 0;
}
bool complete() const
{
if (!in_data)
return false;
return (hdr.nMessageSize == nDataPos);
}
void SetVersion(int nVersionIn)
{
hdrbuf.SetVersion(nVersionIn);
vRecv.SetVersion(nVersionIn);
}
int readHeader(const char *pch, unsigned int nBytes);
int readData(const char *pch, unsigned int nBytes);
};
/** Information about a peer */
class CNode
{
public:
// socket
ServiceFlags nServices;
ServiceFlags nServicesExpected;
SOCKET hSocket;
CDataStream ssSend;
size_t nSendSize; // total size of all vSendMsg entries
size_t nSendOffset; // offset inside the first vSendMsg already sent
uint64_t nSendBytes;
std::deque<CSerializeData> 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;
bool fInbound;
bool fNetworkNode;
bool fSuccessfullyConnected;
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;
NodeId id;
const uint64_t nKeyedNetGroup;
protected:
// Denial-of-service detection/prevention
// Key is IP address, value is banned-until-time
static banmap_t setBanned;
static CCriticalSection cs_setBanned;
static bool setBannedIsDirty;
// Whitelisted ranges. Any node connecting from these is automatically
// whitelisted (as well as those connecting to whitelisted binds).
static std::vector<CSubNet> vWhitelistedRange;
static CCriticalSection cs_vWhitelistedRange;
mapMsgCmdSize mapSendBytesPerMsgCmd;
mapMsgCmdSize mapRecvBytesPerMsgCmd;
// Basic fuzz-testing
void Fuzz(int nChance); // modifies ssSend
public:
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(SOCKET hSocketIn, const CAddress &addrIn, const std::string &addrNameIn = "", bool fInboundIn = false);
~CNode();
private:
// Network usage totals
static CCriticalSection cs_totalBytesRecv;
static CCriticalSection cs_totalBytesSent;
static uint64_t nTotalBytesRecv;
static uint64_t nTotalBytesSent;
// outbound limit & stats
static uint64_t nMaxOutboundTotalBytesSentInCycle;
static uint64_t nMaxOutboundCycleStartTime;
static uint64_t nMaxOutboundLimit;
static uint64_t nMaxOutboundTimeframe;
CNode(const CNode&);
void operator=(const CNode&);
static uint64_t CalculateKeyedNetGroup(const CAddress& ad);
public:
NodeId GetId() const {
return id;
}
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);
// requires LOCK(cs_vRecvMsg)
void SetRecvVersion(int nVersionIn)
{
nRecvVersion = nVersionIn;
BOOST_FOREACH(CNetMessage &msg, vRecvMsg)
msg.SetVersion(nVersionIn);
}
CNode* AddRef()
{
nRefCount++;
return this;
}
void Release()
{
nRefCount--;
}
void AddAddressKnown(const CAddress& _addr)
{
addrKnown.insert(_addr.GetKey());
}
void PushAddress(const CAddress& _addr)
{
// 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() % vAddrToSend.size()] = _addr;
} else {
vAddrToSend.push_back(_addr);
}
}
}
void AddInventoryKnown(const CInv& inv)
{
{
LOCK(cs_inventory);
filterInventoryKnown.insert(inv.hash);
}
}
void PushInventory(const CInv& inv)
{
LOCK(cs_inventory);
if (inv.type == MSG_TX) {
if (!filterInventoryKnown.contains(inv.hash)) {
setInventoryTxToSend.insert(inv.hash);
}
} else if (inv.type == MSG_BLOCK) {
vInventoryBlockToSend.push_back(inv.hash);
}
}
void PushBlockHash(const uint256 &hash)
{
LOCK(cs_inventory);
vBlockHashesToAnnounce.push_back(hash);
}
void AskFor(const CInv& inv);
// TODO: Document the postcondition of this function. Is cs_vSend locked?
void BeginMessage(const char* pszCommand) EXCLUSIVE_LOCK_FUNCTION(cs_vSend);
// TODO: Document the precondition of this function. Is cs_vSend locked?
void AbortMessage() UNLOCK_FUNCTION(cs_vSend);
// TODO: Document the precondition of this function. Is cs_vSend locked?
void EndMessage(const char* pszCommand) UNLOCK_FUNCTION(cs_vSend);
void PushVersion();
void PushMessage(const char* pszCommand)
{
try
{
BeginMessage(pszCommand);
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1>
void PushMessage(const char* pszCommand, const T1& a1)
{
try
{
BeginMessage(pszCommand);
ssSend << a1;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
/** Send a message containing a1, serialized with flag flag. */
template<typename T1>
void PushMessageWithFlag(int flag, const char* pszCommand, const T1& a1)
{
try
{
BeginMessage(pszCommand);
WithOrVersion(&ssSend, flag) << a1;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3, typename T4>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3 << a4;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3, typename T4, typename T5>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3 << a4 << a5;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3, typename T4, typename T5, typename T6>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3 << a4 << a5 << a6;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6, const T7& a7)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3 << a4 << a5 << a6 << a7;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6, const T7& a7, const T8& a8)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3 << a4 << a5 << a6 << a7 << a8;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
template<typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8, typename T9>
void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6, const T7& a7, const T8& a8, const T9& a9)
{
try
{
BeginMessage(pszCommand);
ssSend << a1 << a2 << a3 << a4 << a5 << a6 << a7 << a8 << a9;
EndMessage(pszCommand);
}
catch (...)
{
AbortMessage();
throw;
}
}
void CloseSocketDisconnect();
// 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.
static void ClearBanned(); // needed for unit testing
static bool IsBanned(CNetAddr ip);
static bool IsBanned(CSubNet subnet);
static void Ban(const CNetAddr &ip, const BanReason &banReason, int64_t bantimeoffset = 0, bool sinceUnixEpoch = false);
static void Ban(const CSubNet &subNet, const BanReason &banReason, int64_t bantimeoffset = 0, bool sinceUnixEpoch = false);
static bool Unban(const CNetAddr &ip);
static bool Unban(const CSubNet &ip);
static void GetBanned(banmap_t &banmap);
static void SetBanned(const banmap_t &banmap);
//!check is the banlist has unwritten changes
static bool BannedSetIsDirty();
//!set the "dirty" flag for the banlist
static void SetBannedSetDirty(bool dirty=true);
//!clean unused entries (if bantime has expired)
static void SweepBanned();
void copyStats(CNodeStats &stats);
static bool IsWhitelistedRange(const CNetAddr &ip);
static void AddWhitelistedRange(const CSubNet &subnet);
// Network stats
static void RecordBytesRecv(uint64_t bytes);
static void RecordBytesSent(uint64_t bytes);
static uint64_t GetTotalBytesRecv();
static uint64_t GetTotalBytesSent();
//!set the max outbound target in bytes
static void SetMaxOutboundTarget(uint64_t limit);
static uint64_t GetMaxOutboundTarget();
//!set the timeframe for the max outbound target
static void SetMaxOutboundTimeframe(uint64_t timeframe);
static 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
static bool OutboundTargetReached(bool historicalBlockServingLimit);
//!response the bytes left in the current max outbound cycle
// in case of no limit, it will always response 0
static 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
static uint64_t GetMaxOutboundTimeLeftInCycle();
};
class CTransaction;
void RelayTransaction(const CTransaction& tx);
/** Return a timestamp in the future (in microseconds) for exponentially distributed events. */
int64_t PoissonNextSend(int64_t nNow, int average_interval_seconds);
struct AddedNodeInfo
{
std::string strAddedNode;
CService resolvedAddress;
bool fConnected;
bool fInbound;
};
std::vector<AddedNodeInfo> GetAddedNodeInfo();
#endif // BITCOIN_NET_H