starwels/src/net.cpp

// 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.

#if defined(HAVE_CONFIG_H)
#include "config/bitcoin-config.h"
#endif

#include "net.h"

#include "addrman.h"
#include "chainparams.h"
#include "clientversion.h"
#include "consensus/consensus.h"
#include "crypto/common.h"
#include "crypto/sha256.h"
#include "hash.h"
#include "primitives/transaction.h"
#include "netbase.h"
#include "scheduler.h"
#include "ui_interface.h"
#include "utilstrencodings.h"

#ifdef WIN32
#include <string.h>
#else
#include <fcntl.h>
#endif

#ifdef USE_UPNP
#include <miniupnpc/miniupnpc.h>
#include <miniupnpc/miniwget.h>
#include <miniupnpc/upnpcommands.h>
#include <miniupnpc/upnperrors.h>
#endif

#include <boost/filesystem.hpp>
#include <boost/thread.hpp>

#include <math.h>

// Dump addresses to peers.dat and banlist.dat every 15 minutes (900s)
#define DUMP_ADDRESSES_INTERVAL 900

// We add a random period time (0 to 1 seconds) to feeler connections to prevent synchronization.
#define FEELER_SLEEP_WINDOW 1

#if !defined(HAVE_MSG_NOSIGNAL) && !defined(MSG_NOSIGNAL)
#define MSG_NOSIGNAL 0
#endif

// Fix for ancient MinGW versions, that don't have defined these in ws2tcpip.h.
// Todo: Can be removed when our pull-tester is upgraded to a modern MinGW version.
#ifdef WIN32
#ifndef PROTECTION_LEVEL_UNRESTRICTED
#define PROTECTION_LEVEL_UNRESTRICTED 10
#endif
#ifndef IPV6_PROTECTION_LEVEL
#define IPV6_PROTECTION_LEVEL 23
#endif
#endif

const static 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]
//
// Global state variables
//
bool fDiscover = true;
bool fListen = true;
bool fRelayTxes = true;
CCriticalSection cs_mapLocalHost;
std::map<CNetAddr, LocalServiceInfo> mapLocalHost;
static bool vfLimited[NET_MAX] = {};
std::string strSubVersion;

limitedmap<uint256, int64_t> mapAlreadyAskedFor(MAX_INV_SZ);

// Signals for message handling
static CNodeSignals g_signals;
CNodeSignals& GetNodeSignals() { return g_signals; }

void CConnman::AddOneShot(const std::string& strDest)
{
    LOCK(cs_vOneShots);
    vOneShots.push_back(strDest);
}

unsigned short GetListenPort()
{
    return (unsigned short)(GetArg("-port", Params().GetDefaultPort()));
}

// find 'best' local address for a particular peer
bool GetLocal(CService& addr, const CNetAddr *paddrPeer)
{
    if (!fListen)
        return false;

    int nBestScore = -1;
    int nBestReachability = -1;
    {
        LOCK(cs_mapLocalHost);
        for (std::map<CNetAddr, LocalServiceInfo>::iterator it = mapLocalHost.begin(); it != mapLocalHost.end(); it++)
        {
            int nScore = (*it).second.nScore;
            int nReachability = (*it).first.GetReachabilityFrom(paddrPeer);
            if (nReachability > nBestReachability || (nReachability == nBestReachability && nScore > nBestScore))
            {
                addr = CService((*it).first, (*it).second.nPort);
                nBestReachability = nReachability;
                nBestScore = nScore;
            }
        }
    }
    return nBestScore >= 0;
}

//! Convert the pnSeeds6 array into usable address objects.
static std::vector<CAddress> convertSeed6(const std::vector<SeedSpec6> &vSeedsIn)
{
    // It'll only connect to one or two seed nodes because once it connects,
    // it'll get a pile of addresses with newer timestamps.
    // Seed nodes are given a random 'last seen time' of between one and two
    // weeks ago.
    const int64_t nOneWeek = 7*24*60*60;
    std::vector<CAddress> vSeedsOut;
    vSeedsOut.reserve(vSeedsIn.size());
    for (std::vector<SeedSpec6>::const_iterator i(vSeedsIn.begin()); i != vSeedsIn.end(); ++i)
    {
        struct in6_addr ip;
        memcpy(&ip, i->addr, sizeof(ip));
        CAddress addr(CService(ip, i->port), NODE_NETWORK);
        addr.nTime = GetTime() - GetRand(nOneWeek) - nOneWeek;
        vSeedsOut.push_back(addr);
    }
    return vSeedsOut;
}

// get best local address for a particular peer as a CAddress
// Otherwise, return the unroutable 0.0.0.0 but filled in with
// the normal parameters, since the IP may be changed to a useful
// one by discovery.
CAddress GetLocalAddress(const CNetAddr *paddrPeer, ServiceFlags nLocalServices)
{
    CAddress ret(CService(CNetAddr(),GetListenPort()), NODE_NONE);
    CService addr;
    if (GetLocal(addr, paddrPeer))
    {
        ret = CAddress(addr, nLocalServices);
    }
    ret.nTime = GetAdjustedTime();
    return ret;
}

int GetnScore(const CService& addr)
{
    LOCK(cs_mapLocalHost);
    if (mapLocalHost.count(addr) == LOCAL_NONE)
        return 0;
    return mapLocalHost[addr].nScore;
}

// Is our peer's addrLocal potentially useful as an external IP source?
bool IsPeerAddrLocalGood(CNode *pnode)
{
    return fDiscover && pnode->addr.IsRoutable() && pnode->addrLocal.IsRoutable() &&
           !IsLimited(pnode->addrLocal.GetNetwork());
}

// pushes our own address to a peer
void AdvertiseLocal(CNode *pnode)
{
    if (fListen && pnode->fSuccessfullyConnected)
    {
        CAddress addrLocal = GetLocalAddress(&pnode->addr, pnode->GetLocalServices());
        // If discovery is enabled, sometimes give our peer the address it
        // tells us that it sees us as in case it has a better idea of our
        // address than we do.
        if (IsPeerAddrLocalGood(pnode) && (!addrLocal.IsRoutable() ||
             GetRand((GetnScore(addrLocal) > LOCAL_MANUAL) ? 8:2) == 0))
        {
            addrLocal.SetIP(pnode->addrLocal);
        }
        if (addrLocal.IsRoutable())
        {
            LogPrint("net", "AdvertiseLocal: advertising address %s\n", addrLocal.ToString());
            FastRandomContext insecure_rand;
            pnode->PushAddress(addrLocal, insecure_rand);
        }
    }
}

// learn a new local address
bool AddLocal(const CService& addr, int nScore)
{
    if (!addr.IsRoutable())
        return false;

    if (!fDiscover && nScore < LOCAL_MANUAL)
        return false;

    if (IsLimited(addr))
        return false;

    LogPrintf("AddLocal(%s,%i)\n", addr.ToString(), nScore);

    {
        LOCK(cs_mapLocalHost);
        bool fAlready = mapLocalHost.count(addr) > 0;
        LocalServiceInfo &info = mapLocalHost[addr];
        if (!fAlready || nScore >= info.nScore) {
            info.nScore = nScore + (fAlready ? 1 : 0);
            info.nPort = addr.GetPort();
        }
    }

    return true;
}

bool AddLocal(const CNetAddr &addr, int nScore)
{
    return AddLocal(CService(addr, GetListenPort()), nScore);
}

bool RemoveLocal(const CService& addr)
{
    LOCK(cs_mapLocalHost);
    LogPrintf("RemoveLocal(%s)\n", addr.ToString());
    mapLocalHost.erase(addr);
    return true;
}

/** Make a particular network entirely off-limits (no automatic connects to it) */
void SetLimited(enum Network net, bool fLimited)
{
    if (net == NET_UNROUTABLE)
        return;
    LOCK(cs_mapLocalHost);
    vfLimited[net] = fLimited;
}

bool IsLimited(enum Network net)
{
    LOCK(cs_mapLocalHost);
    return vfLimited[net];
}

bool IsLimited(const CNetAddr &addr)
{
    return IsLimited(addr.GetNetwork());
}

/** vote for a local address */
bool SeenLocal(const CService& addr)
{
    {
        LOCK(cs_mapLocalHost);
        if (mapLocalHost.count(addr) == 0)
            return false;
        mapLocalHost[addr].nScore++;
    }
    return true;
}


/** check whether a given address is potentially local */
bool IsLocal(const CService& addr)
{
    LOCK(cs_mapLocalHost);
    return mapLocalHost.count(addr) > 0;
}

/** check whether a given network is one we can probably connect to */
bool IsReachable(enum Network net)
{
    LOCK(cs_mapLocalHost);
    return !vfLimited[net];
}

/** check whether a given address is in a network we can probably connect to */
bool IsReachable(const CNetAddr& addr)
{
    enum Network net = addr.GetNetwork();
    return IsReachable(net);
}


CNode* CConnman::FindNode(const CNetAddr& ip)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
        if ((CNetAddr)pnode->addr == ip)
            return (pnode);
    return NULL;
}

CNode* CConnman::FindNode(const CSubNet& subNet)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
    if (subNet.Match((CNetAddr)pnode->addr))
        return (pnode);
    return NULL;
}

CNode* CConnman::FindNode(const std::string& addrName)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
        if (pnode->addrName == addrName)
            return (pnode);
    return NULL;
}

CNode* CConnman::FindNode(const CService& addr)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
        if ((CService)pnode->addr == addr)
            return (pnode);
    return NULL;
}

bool CConnman::CheckIncomingNonce(uint64_t nonce)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes) {
        if (!pnode->fSuccessfullyConnected && !pnode->fInbound && pnode->GetLocalNonce() == nonce)
            return false;
    }
    return true;
}

CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure)
{
    if (pszDest == NULL) {
        if (IsLocal(addrConnect))
            return NULL;

        // Look for an existing connection
        CNode* pnode = FindNode((CService)addrConnect);
        if (pnode)
        {
            pnode->AddRef();
            return pnode;
        }
    }

    /// debug print
    LogPrint("net", "trying connection %s lastseen=%.1fhrs\n",
        pszDest ? pszDest : addrConnect.ToString(),
        pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);

    // Connect
    SOCKET hSocket;
    bool proxyConnectionFailed = false;
    if (pszDest ? ConnectSocketByName(addrConnect, hSocket, pszDest, Params().GetDefaultPort(), nConnectTimeout, &proxyConnectionFailed) :
                  ConnectSocket(addrConnect, hSocket, nConnectTimeout, &proxyConnectionFailed))
    {
        if (!IsSelectableSocket(hSocket)) {
            LogPrintf("Cannot create connection: non-selectable socket created (fd >= FD_SETSIZE ?)\n");
            CloseSocket(hSocket);
            return NULL;
        }

        if (pszDest && addrConnect.IsValid()) {
            // It is possible that we already have a connection to the IP/port pszDest resolved to.
            // In that case, drop the connection that was just created, and return the existing CNode instead.
            // Also store the name we used to connect in that CNode, so that future FindNode() calls to that
            // name catch this early.
            CNode* pnode = FindNode((CService)addrConnect);
            if (pnode)
            {
                pnode->AddRef();
                {
                    LOCK(cs_vNodes);
                    if (pnode->addrName.empty()) {
                        pnode->addrName = std::string(pszDest);
                    }
                }
                CloseSocket(hSocket);
                return pnode;
            }
        }

        addrman.Attempt(addrConnect, fCountFailure);

        // Add node
        NodeId id = GetNewNodeId();
        uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize();
        CNode* pnode = new CNode(id, nLocalServices, GetBestHeight(), hSocket, addrConnect, CalculateKeyedNetGroup(addrConnect), nonce, pszDest ? pszDest : "", false);
        pnode->nServicesExpected = ServiceFlags(addrConnect.nServices & nRelevantServices);
        pnode->nTimeConnected = GetTime();
        pnode->AddRef();
        GetNodeSignals().InitializeNode(pnode, *this);
        {
            LOCK(cs_vNodes);
            vNodes.push_back(pnode);
        }

        return pnode;
    } else if (!proxyConnectionFailed) {
        // If connecting to the node failed, and failure is not caused by a problem connecting to
        // the proxy, mark this as an attempt.
        addrman.Attempt(addrConnect, fCountFailure);
    }

    return NULL;
}

void CConnman::DumpBanlist()
{
    SweepBanned(); // clean unused entries (if bantime has expired)

    if (!BannedSetIsDirty())
        return;

    int64_t nStart = GetTimeMillis();

    CBanDB bandb;
    banmap_t banmap;
    SetBannedSetDirty(false);
    GetBanned(banmap);
    if (!bandb.Write(banmap))
        SetBannedSetDirty(true);

    LogPrint("net", "Flushed %d banned node ips/subnets to banlist.dat  %dms\n",
        banmap.size(), GetTimeMillis() - nStart);
}

void CNode::CloseSocketDisconnect()
{
    fDisconnect = true;
    if (hSocket != INVALID_SOCKET)
    {
        LogPrint("net", "disconnecting peer=%d\n", id);
        CloseSocket(hSocket);
    }

    // in case this fails, we'll empty the recv buffer when the CNode is deleted
    TRY_LOCK(cs_vRecvMsg, lockRecv);
    if (lockRecv)
        vRecvMsg.clear();
}

void CConnman::ClearBanned()
{
    {
        LOCK(cs_setBanned);
        setBanned.clear();
        setBannedIsDirty = true;
    }
    DumpBanlist(); //store banlist to disk
    if(clientInterface)
        clientInterface->BannedListChanged();
}

bool CConnman::IsBanned(CNetAddr ip)
{
    bool fResult = false;
    {
        LOCK(cs_setBanned);
        for (banmap_t::iterator it = setBanned.begin(); it != setBanned.end(); it++)
        {
            CSubNet subNet = (*it).first;
            CBanEntry banEntry = (*it).second;

            if(subNet.Match(ip) && GetTime() < banEntry.nBanUntil)
                fResult = true;
        }
    }
    return fResult;
}

bool CConnman::IsBanned(CSubNet subnet)
{
    bool fResult = false;
    {
        LOCK(cs_setBanned);
        banmap_t::iterator i = setBanned.find(subnet);
        if (i != setBanned.end())
        {
            CBanEntry banEntry = (*i).second;
            if (GetTime() < banEntry.nBanUntil)
                fResult = true;
        }
    }
    return fResult;
}

void CConnman::Ban(const CNetAddr& addr, const BanReason &banReason, int64_t bantimeoffset, bool sinceUnixEpoch) {
    CSubNet subNet(addr);
    Ban(subNet, banReason, bantimeoffset, sinceUnixEpoch);
}

void CConnman::Ban(const CSubNet& subNet, const BanReason &banReason, int64_t bantimeoffset, bool sinceUnixEpoch) {
    CBanEntry banEntry(GetTime());
    banEntry.banReason = banReason;
    if (bantimeoffset <= 0)
    {
        bantimeoffset = GetArg("-bantime", DEFAULT_MISBEHAVING_BANTIME);
        sinceUnixEpoch = false;
    }
    banEntry.nBanUntil = (sinceUnixEpoch ? 0 : GetTime() )+bantimeoffset;

    {
        LOCK(cs_setBanned);
        if (setBanned[subNet].nBanUntil < banEntry.nBanUntil) {
            setBanned[subNet] = banEntry;
            setBannedIsDirty = true;
        }
        else
            return;
    }
    if(clientInterface)
        clientInterface->BannedListChanged();
    {
        LOCK(cs_vNodes);
        BOOST_FOREACH(CNode* pnode, vNodes) {
            if (subNet.Match((CNetAddr)pnode->addr))
                pnode->fDisconnect = true;
        }
    }
    if(banReason == BanReasonManuallyAdded)
        DumpBanlist(); //store banlist to disk immediately if user requested ban
}

bool CConnman::Unban(const CNetAddr &addr) {
    CSubNet subNet(addr);
    return Unban(subNet);
}

bool CConnman::Unban(const CSubNet &subNet) {
    {
        LOCK(cs_setBanned);
        if (!setBanned.erase(subNet))
            return false;
        setBannedIsDirty = true;
    }
    if(clientInterface)
        clientInterface->BannedListChanged();
    DumpBanlist(); //store banlist to disk immediately
    return true;
}

void CConnman::GetBanned(banmap_t &banMap)
{
    LOCK(cs_setBanned);
    banMap = setBanned; //create a thread safe copy
}

void CConnman::SetBanned(const banmap_t &banMap)
{
    LOCK(cs_setBanned);
    setBanned = banMap;
    setBannedIsDirty = true;
}

void CConnman::SweepBanned()
{
    int64_t now = GetTime();

    LOCK(cs_setBanned);
    banmap_t::iterator it = setBanned.begin();
    while(it != setBanned.end())
    {
        CSubNet subNet = (*it).first;
        CBanEntry banEntry = (*it).second;
        if(now > banEntry.nBanUntil)
        {
            setBanned.erase(it++);
            setBannedIsDirty = true;
            LogPrint("net", "%s: Removed banned node ip/subnet from banlist.dat: %s\n", __func__, subNet.ToString());
        }
        else
            ++it;
    }
}

bool CConnman::BannedSetIsDirty()
{
    LOCK(cs_setBanned);
    return setBannedIsDirty;
}

void CConnman::SetBannedSetDirty(bool dirty)
{
    LOCK(cs_setBanned); //reuse setBanned lock for the isDirty flag
    setBannedIsDirty = dirty;
}


bool CConnman::IsWhitelistedRange(const CNetAddr &addr) {
    LOCK(cs_vWhitelistedRange);
    BOOST_FOREACH(const CSubNet& subnet, vWhitelistedRange) {
        if (subnet.Match(addr))
            return true;
    }
    return false;
}

void CConnman::AddWhitelistedRange(const CSubNet &subnet) {
    LOCK(cs_vWhitelistedRange);
    vWhitelistedRange.push_back(subnet);
}

#undef X
#define X(name) stats.name = name
void CNode::copyStats(CNodeStats &stats)
{
    stats.nodeid = this->GetId();
    X(nServices);
    X(addr);
    X(fRelayTxes);
    X(nLastSend);
    X(nLastRecv);
    X(nTimeConnected);
    X(nTimeOffset);
    X(addrName);
    X(nVersion);
    X(cleanSubVer);
    X(fInbound);
    X(nStartingHeight);
    X(nSendBytes);
    X(mapSendBytesPerMsgCmd);
    X(nRecvBytes);
    X(mapRecvBytesPerMsgCmd);
    X(fWhitelisted);

    // It is common for nodes with good ping times to suddenly become lagged,
    // due to a new block arriving or other large transfer.
    // Merely reporting pingtime might fool the caller into thinking the node was still responsive,
    // since pingtime does not update until the ping is complete, which might take a while.
    // So, if a ping is taking an unusually long time in flight,
    // the caller can immediately detect that this is happening.
    int64_t nPingUsecWait = 0;
    if ((0 != nPingNonceSent) && (0 != nPingUsecStart)) {
        nPingUsecWait = GetTimeMicros() - nPingUsecStart;
    }

    // Raw ping time is in microseconds, but show it to user as whole seconds (Bitcoin users should be well used to small numbers with many decimal places by now :)
    stats.dPingTime = (((double)nPingUsecTime) / 1e6);
    stats.dMinPing  = (((double)nMinPingUsecTime) / 1e6);
    stats.dPingWait = (((double)nPingUsecWait) / 1e6);