src/net.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2015 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #if defined(HAVE_CONFIG_H)
   7 #include "config/bitcoin-config.h"
   8 #endif
   9
  10 #include "net.h"
  11
  12 #include "addrman.h"
  13 #include "chainparams.h"
  14 #include "clientversion.h"
  15 #include "consensus/consensus.h"
  16 #include "crypto/common.h"
  17 #include "crypto/sha256.h"
  18 #include "hash.h"
  19 #include "primitives/transaction.h"
  20 #include "netbase.h"
  21 #include "scheduler.h"
  22 #include "ui_interface.h"
  23 #include "utilstrencodings.h"
  24
  25 #ifdef WIN32
  26 #include <string.h>
  27 #else
  28 #include <fcntl.h>
  29 #endif
  30
  31 #ifdef USE_UPNP
  32 #include <miniupnpc/miniupnpc.h>
  33 #include <miniupnpc/miniwget.h>
  34 #include <miniupnpc/upnpcommands.h>
  35 #include <miniupnpc/upnperrors.h>
  36 #endif
  37
  38 #include <boost/filesystem.hpp>
  39 #include <boost/thread.hpp>
  40
  41 #include <math.h>
  42
  43 // Dump addresses to peers.dat and banlist.dat every 15 minutes (900s)
  44 #define DUMP_ADDRESSES_INTERVAL 900
  45
  46 // We add a random period time (0 to 1 seconds) to feeler connections to prevent synchronization.
  47 #define FEELER_SLEEP_WINDOW 1
  48
  49 #if !defined(HAVE_MSG_NOSIGNAL) && !defined(MSG_NOSIGNAL)
  50 #define MSG_NOSIGNAL 0
  51 #endif
  52
  53 // Fix for ancient MinGW versions, that don't have defined these in ws2tcpip.h.
  54 // Todo: Can be removed when our pull-tester is upgraded to a modern MinGW version.
  55 #ifdef WIN32
  56 #ifndef PROTECTION_LEVEL_UNRESTRICTED
  57 #define PROTECTION_LEVEL_UNRESTRICTED 10
  58 #endif
  59 #ifndef IPV6_PROTECTION_LEVEL
  60 #define IPV6_PROTECTION_LEVEL 23
  61 #endif
  62 #endif
  63
  64
  65 namespace {
  66     const int MAX_FEELER_CONNECTIONS = 1;
  67 }
  68
  69 const static std::string NET_MESSAGE_COMMAND_OTHER = "*other*";
  70
  71 //
  72 // Global state variables
  73 //
  74 bool fDiscover = true;
  75 bool fListen = true;
  76 bool fRelayTxes = true;
  77 CCriticalSection cs_mapLocalHost;
  78 std::map<CNetAddr, LocalServiceInfo> mapLocalHost;
  79 static bool vfLimited[NET_MAX] = {};
  80 static CNode* pnodeLocalHost = NULL;
  81 std::string strSubVersion;
  82
  83 limitedmap<uint256, int64_t> mapAlreadyAskedFor(MAX_INV_SZ);
  84
  85 // Signals for message handling
  86 static CNodeSignals g_signals;
  87 CNodeSignals& GetNodeSignals() { return g_signals; }
  88
  89 void CConnman::AddOneShot(const std::string& strDest)
  90 {
  91     LOCK(cs_vOneShots);
  92     vOneShots.push_back(strDest);
  93 }
  94
  95 unsigned short GetListenPort()
  96 {
  97     return (unsigned short)(GetArg("-port", Params().GetDefaultPort()));
  98 }
  99
 100 // find 'best' local address for a particular peer
 101 bool GetLocal(CService& addr, const CNetAddr *paddrPeer)
 102 {
 103     if (!fListen)
 104         return false;
 105
 106     int nBestScore = -1;
 107     int nBestReachability = -1;
 108     {
 109         LOCK(cs_mapLocalHost);
 110         for (std::map<CNetAddr, LocalServiceInfo>::iterator it = mapLocalHost.begin(); it != mapLocalHost.end(); it++)
 111         {
 112             int nScore = (*it).second.nScore;
 113             int nReachability = (*it).first.GetReachabilityFrom(paddrPeer);
 114             if (nReachability > nBestReachability || (nReachability == nBestReachability && nScore > nBestScore))
 115             {
 116                 addr = CService((*it).first, (*it).second.nPort);
 117                 nBestReachability = nReachability;
 118                 nBestScore = nScore;
 119             }
 120         }
 121     }
 122     return nBestScore >= 0;
 123 }
 124
 125 //! Convert the pnSeeds6 array into usable address objects.
 126 static std::vector<CAddress> convertSeed6(const std::vector<SeedSpec6> &vSeedsIn)
 127 {
 128     // It'll only connect to one or two seed nodes because once it connects,
 129     // it'll get a pile of addresses with newer timestamps.
 130     // Seed nodes are given a random 'last seen time' of between one and two
 131     // weeks ago.
 132     const int64_t nOneWeek = 7*24*60*60;
 133     std::vector<CAddress> vSeedsOut;
 134     vSeedsOut.reserve(vSeedsIn.size());
 135     for (std::vector<SeedSpec6>::const_iterator i(vSeedsIn.begin()); i != vSeedsIn.end(); ++i)
 136     {
 137         struct in6_addr ip;
 138         memcpy(&ip, i->addr, sizeof(ip));
 139         CAddress addr(CService(ip, i->port), NODE_NETWORK);
 140         addr.nTime = GetTime() - GetRand(nOneWeek) - nOneWeek;
 141         vSeedsOut.push_back(addr);
 142     }
 143     return vSeedsOut;
 144 }
 145
 146 // get best local address for a particular peer as a CAddress
 147 // Otherwise, return the unroutable 0.0.0.0 but filled in with
 148 // the normal parameters, since the IP may be changed to a useful
 149 // one by discovery.
 150 CAddress GetLocalAddress(const CNetAddr *paddrPeer, ServiceFlags nLocalServices)
 151 {
 152     CAddress ret(CService(CNetAddr(),GetListenPort()), NODE_NONE);
 153     CService addr;
 154     if (GetLocal(addr, paddrPeer))
 155     {
 156         ret = CAddress(addr, nLocalServices);
 157     }
 158     ret.nTime = GetAdjustedTime();
 159     return ret;
 160 }
 161
 162 int GetnScore(const CService& addr)
 163 {
 164     LOCK(cs_mapLocalHost);
 165     if (mapLocalHost.count(addr) == LOCAL_NONE)
 166         return 0;
 167     return mapLocalHost[addr].nScore;
 168 }
 169
 170 // Is our peer's addrLocal potentially useful as an external IP source?
 171 bool IsPeerAddrLocalGood(CNode *pnode)
 172 {
 173     return fDiscover && pnode->addr.IsRoutable() && pnode->addrLocal.IsRoutable() &&
 174            !IsLimited(pnode->addrLocal.GetNetwork());
 175 }
 176
 177 // pushes our own address to a peer
 178 void AdvertiseLocal(CNode *pnode)
 179 {
 180     if (fListen && pnode->fSuccessfullyConnected)
 181     {
 182         CAddress addrLocal = GetLocalAddress(&pnode->addr, pnode->GetLocalServices());
 183         // If discovery is enabled, sometimes give our peer the address it
 184         // tells us that it sees us as in case it has a better idea of our
 185         // address than we do.
 186         if (IsPeerAddrLocalGood(pnode) && (!addrLocal.IsRoutable() ||
 187              GetRand((GetnScore(addrLocal) > LOCAL_MANUAL) ? 8:2) == 0))
 188         {
 189             addrLocal.SetIP(pnode->addrLocal);
 190         }
 191         if (addrLocal.IsRoutable())
 192         {
 193             LogPrint("net", "AdvertiseLocal: advertising address %s\n", addrLocal.ToString());
 194             pnode->PushAddress(addrLocal);
 195         }
 196     }
 197 }
 198
 199 // learn a new local address
 200 bool AddLocal(const CService& addr, int nScore)
 201 {
 202     if (!addr.IsRoutable())
 203         return false;
 204
 205     if (!fDiscover && nScore < LOCAL_MANUAL)
 206         return false;
 207
 208     if (IsLimited(addr))
 209         return false;
 210
 211     LogPrintf("AddLocal(%s,%i)\n", addr.ToString(), nScore);
 212
 213     {
 214         LOCK(cs_mapLocalHost);
 215         bool fAlready = mapLocalHost.count(addr) > 0;
 216         LocalServiceInfo &info = mapLocalHost[addr];
 217         if (!fAlready || nScore >= info.nScore) {
 218             info.nScore = nScore + (fAlready ? 1 : 0);
 219             info.nPort = addr.GetPort();
 220         }
 221     }
 222
 223     return true;
 224 }
 225
 226 bool AddLocal(const CNetAddr &addr, int nScore)
 227 {
 228     return AddLocal(CService(addr, GetListenPort()), nScore);
 229 }
 230
 231 bool RemoveLocal(const CService& addr)
 232 {
 233     LOCK(cs_mapLocalHost);
 234     LogPrintf("RemoveLocal(%s)\n", addr.ToString());
 235     mapLocalHost.erase(addr);
 236     return true;
 237 }
 238
 239 /** Make a particular network entirely off-limits (no automatic connects to it) */
 240 void SetLimited(enum Network net, bool fLimited)
 241 {
 242     if (net == NET_UNROUTABLE)
 243         return;
 244     LOCK(cs_mapLocalHost);
 245     vfLimited[net] = fLimited;
 246 }
 247
 248 bool IsLimited(enum Network net)
 249 {
 250     LOCK(cs_mapLocalHost);
 251     return vfLimited[net];
 252 }
 253
 254 bool IsLimited(const CNetAddr &addr)
 255 {
 256     return IsLimited(addr.GetNetwork());
 257 }
 258
 259 /** vote for a local address */
 260 bool SeenLocal(const CService& addr)
 261 {
 262     {
 263         LOCK(cs_mapLocalHost);
 264         if (mapLocalHost.count(addr) == 0)
 265             return false;
 266         mapLocalHost[addr].nScore++;
 267     }
 268     return true;
 269 }
 270
 271
 272 /** check whether a given address is potentially local */
 273 bool IsLocal(const CService& addr)
 274 {
 275     LOCK(cs_mapLocalHost);
 276     return mapLocalHost.count(addr) > 0;
 277 }
 278
 279 /** check whether a given network is one we can probably connect to */
 280 bool IsReachable(enum Network net)
 281 {
 282     LOCK(cs_mapLocalHost);
 283     return !vfLimited[net];
 284 }
 285
 286 /** check whether a given address is in a network we can probably connect to */
 287 bool IsReachable(const CNetAddr& addr)
 288 {
 289     enum Network net = addr.GetNetwork();
 290     return IsReachable(net);
 291 }
 292
 293
 294 CNode* CConnman::FindNode(const CNetAddr& ip)
 295 {
 296     LOCK(cs_vNodes);
 297     BOOST_FOREACH(CNode* pnode, vNodes)
 298         if ((CNetAddr)pnode->addr == ip)
 299             return (pnode);
 300     return NULL;
 301 }
 302
 303 CNode* CConnman::FindNode(const CSubNet& subNet)
 304 {
 305     LOCK(cs_vNodes);
 306     BOOST_FOREACH(CNode* pnode, vNodes)
 307     if (subNet.Match((CNetAddr)pnode->addr))
 308         return (pnode);
 309     return NULL;
 310 }
 311
 312 CNode* CConnman::FindNode(const std::string& addrName)
 313 {
 314     LOCK(cs_vNodes);
 315     BOOST_FOREACH(CNode* pnode, vNodes)
 316         if (pnode->addrName == addrName)
 317             return (pnode);
 318     return NULL;
 319 }
 320
 321 CNode* CConnman::FindNode(const CService& addr)
 322 {
 323     LOCK(cs_vNodes);
 324     BOOST_FOREACH(CNode* pnode, vNodes)
 325         if ((CService)pnode->addr == addr)
 326             return (pnode);
 327     return NULL;
 328 }
 329
 330 bool CConnman::CheckIncomingNonce(uint64_t nonce)
 331 {
 332     LOCK(cs_vNodes);
 333     BOOST_FOREACH(CNode* pnode, vNodes) {
 334         if (!pnode->fSuccessfullyConnected && !pnode->fInbound && pnode->GetLocalNonce() == nonce)
 335             return false;
 336     }
 337     return true;
 338 }
 339
 340 CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure)
 341 {
 342     if (pszDest == NULL) {
 343         if (IsLocal(addrConnect))
 344             return NULL;
 345
 346         // Look for an existing connection
 347         CNode* pnode = FindNode((CService)addrConnect);
 348         if (pnode)
 349         {
 350             pnode->AddRef();
 351             return pnode;
 352         }
 353     }
 354
 355     /// debug print
 356     LogPrint("net", "trying connection %s lastseen=%.1fhrs\n",
 357         pszDest ? pszDest : addrConnect.ToString(),
 358         pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);
 359
 360     // Connect
 361     SOCKET hSocket;
 362     bool proxyConnectionFailed = false;
 363     if (pszDest ? ConnectSocketByName(addrConnect, hSocket, pszDest, Params().GetDefaultPort(), nConnectTimeout, &proxyConnectionFailed) :
 364                   ConnectSocket(addrConnect, hSocket, nConnectTimeout, &proxyConnectionFailed))
 365     {
 366         if (!IsSelectableSocket(hSocket)) {
 367             LogPrintf("Cannot create connection: non-selectable socket created (fd >= FD_SETSIZE ?)\n");
 368             CloseSocket(hSocket);
 369             return NULL;
 370         }
 371
 372         if (pszDest && addrConnect.IsValid()) {
 373             // It is possible that we already have a connection to the IP/port pszDest resolved to.
 374             // In that case, drop the connection that was just created, and return the existing CNode instead.
 375             // Also store the name we used to connect in that CNode, so that future FindNode() calls to that
 376             // name catch this early.
 377             CNode* pnode = FindNode((CService)addrConnect);
 378             if (pnode)
 379             {
 380                 pnode->AddRef();
 381                 {
 382                     LOCK(cs_vNodes);
 383                     if (pnode->addrName.empty()) {
 384                         pnode->addrName = std::string(pszDest);
 385                     }
 386                 }
 387                 CloseSocket(hSocket);
 388                 return pnode;
 389             }
 390         }
 391
 392         addrman.Attempt(addrConnect, fCountFailure);
 393
 394         // Add node
 395         CNode* pnode = new CNode(GetNewNodeId(), nLocalServices, GetBestHeight(), hSocket, addrConnect, pszDest ? pszDest : "", false);
 396         GetNodeSignals().InitializeNode(pnode->GetId(), pnode);
 397         pnode->AddRef();
 398
 399         {
 400             LOCK(cs_vNodes);
 401             vNodes.push_back(pnode);
 402         }
 403
 404         pnode->nServicesExpected = ServiceFlags(addrConnect.nServices & nRelevantServices);
 405         pnode->nTimeConnected = GetTime();
 406
 407         return pnode;
 408     } else if (!proxyConnectionFailed) {
 409         // If connecting to the node failed, and failure is not caused by a problem connecting to
 410         // the proxy, mark this as an attempt.
 411         addrman.Attempt(addrConnect, fCountFailure);
 412     }
 413
 414     return NULL;
 415 }
 416
 417 void CConnman::DumpBanlist()
 418 {
 419     SweepBanned(); // clean unused entries (if bantime has expired)
 420
 421     if (!BannedSetIsDirty())
 422         return;
 423
 424     int64_t nStart = GetTimeMillis();
 425
 426     CBanDB bandb;
 427     banmap_t banmap;
 428     SetBannedSetDirty(false);
 429     GetBanned(banmap);
 430     if (!bandb.Write(banmap))
 431         SetBannedSetDirty(true);
 432
 433     LogPrint("net", "Flushed %d banned node ips/subnets to banlist.dat  %dms\n",
 434         banmap.size(), GetTimeMillis() - nStart);
 435 }
 436
 437 void CNode::CloseSocketDisconnect()
 438 {
 439     fDisconnect = true;
 440     if (hSocket != INVALID_SOCKET)
 441     {
 442         LogPrint("net", "disconnecting peer=%d\n", id);
 443         CloseSocket(hSocket);
 444     }
 445
 446     // in case this fails, we'll empty the recv buffer when the CNode is deleted
 447     TRY_LOCK(cs_vRecvMsg, lockRecv);
 448     if (lockRecv)
 449         vRecvMsg.clear();
 450 }
 451
 452 void CNode::PushVersion()
 453 {
 454     int64_t nTime = (fInbound ? GetAdjustedTime() : GetTime());
 455     CAddress addrYou = (addr.IsRoutable() && !IsProxy(addr) ? addr : CAddress(CService(), addr.nServices));
 456     CAddress addrMe = GetLocalAddress(&addr, nLocalServices);
 457     if (fLogIPs)
 458         LogPrint("net", "send version message: version %d, blocks=%d, us=%s, them=%s, peer=%d\n", PROTOCOL_VERSION, nMyStartingHeight, addrMe.ToString(), addrYou.ToString(), id);
 459     else
 460         LogPrint("net", "send version message: version %d, blocks=%d, us=%s, peer=%d\n", PROTOCOL_VERSION, nMyStartingHeight, addrMe.ToString(), id);
 461     PushMessage(NetMsgType::VERSION, PROTOCOL_VERSION, (uint64_t)nLocalServices, nTime, addrYou, addrMe,
 462                 nLocalHostNonce, strSubVersion, nMyStartingHeight, ::fRelayTxes);
 463 }
 464
 465
 466
 467
 468
 469 void CConnman::ClearBanned()
 470 {
 471     {
 472         LOCK(cs_setBanned);
 473         setBanned.clear();
 474         setBannedIsDirty = true;
 475     }
 476     DumpBanlist(); //store banlist to disk
 477     uiInterface.BannedListChanged();
 478 }
 479
 480 bool CConnman::IsBanned(CNetAddr ip)
 481 {
 482     bool fResult = false;
 483     {
 484         LOCK(cs_setBanned);
 485         for (banmap_t::iterator it = setBanned.begin(); it != setBanned.end(); it++)
 486         {
 487             CSubNet subNet = (*it).first;
 488             CBanEntry banEntry = (*it).second;
 489
 490             if(subNet.Match(ip) && GetTime() < banEntry.nBanUntil)
 491                 fResult = true;
 492         }
 493     }
 494     return fResult;
 495 }
 496
 497 bool CConnman::IsBanned(CSubNet subnet)
 498 {
 499     bool fResult = false;
 500     {
 501         LOCK(cs_setBanned);
 502         banmap_t::iterator i = setBanned.find(subnet);
 503         if (i != setBanned.end())
 504         {
 505             CBanEntry banEntry = (*i).second;
 506             if (GetTime() < banEntry.nBanUntil)
 507                 fResult = true;
 508         }
 509     }
 510     return fResult;
 511 }
 512
 513 void CConnman::Ban(const CNetAddr& addr, const BanReason &banReason, int64_t bantimeoffset, bool sinceUnixEpoch) {
 514     CSubNet subNet(addr);
 515     Ban(subNet, banReason, bantimeoffset, sinceUnixEpoch);
 516 }
 517
 518 void CConnman::Ban(const CSubNet& subNet, const BanReason &banReason, int64_t bantimeoffset, bool sinceUnixEpoch) {
 519     CBanEntry banEntry(GetTime());
 520     banEntry.banReason = banReason;
 521     if (bantimeoffset <= 0)
 522     {
 523         bantimeoffset = GetArg("-bantime", DEFAULT_MISBEHAVING_BANTIME);
 524         sinceUnixEpoch = false;
 525     }
 526     banEntry.nBanUntil = (sinceUnixEpoch ? 0 : GetTime() )+bantimeoffset;
 527
 528     {
 529         LOCK(cs_setBanned);
 530         if (setBanned[subNet].nBanUntil < banEntry.nBanUntil) {
 531             setBanned[subNet] = banEntry;
 532             setBannedIsDirty = true;
 533         }
 534         else
 535             return;
 536     }
 537     uiInterface.BannedListChanged();
 538     {
 539         LOCK(cs_vNodes);
 540         BOOST_FOREACH(CNode* pnode, vNodes) {
 541             if (subNet.Match((CNetAddr)pnode->addr))
 542                 pnode->fDisconnect = true;
 543         }
 544     }
 545     if(banReason == BanReasonManuallyAdded)
 546         DumpBanlist(); //store banlist to disk immediately if user requested ban
 547 }
 548
 549 bool CConnman::Unban(const CNetAddr &addr) {
 550     CSubNet subNet(addr);
 551     return Unban(subNet);
 552 }
 553
 554 bool CConnman::Unban(const CSubNet &subNet) {
 555     {
 556         LOCK(cs_setBanned);
 557         if (!setBanned.erase(subNet))
 558             return false;
 559         setBannedIsDirty = true;
 560     }
 561     uiInterface.BannedListChanged();
 562     DumpBanlist(); //store banlist to disk immediately
 563     return true;
 564 }
 565
 566 void CConnman::GetBanned(banmap_t &banMap)
 567 {
 568     LOCK(cs_setBanned);
 569     banMap = setBanned; //create a thread safe copy
 570 }
 571
 572 void CConnman::SetBanned(const banmap_t &banMap)
 573 {
 574     LOCK(cs_setBanned);
 575     setBanned = banMap;
 576     setBannedIsDirty = true;
 577 }
 578
 579 void CConnman::SweepBanned()
 580 {
 581     int64_t now = GetTime();
 582
 583     LOCK(cs_setBanned);
 584     banmap_t::iterator it = setBanned.begin();
 585     while(it != setBanned.end())
 586     {
 587         CSubNet subNet = (*it).first;
 588         CBanEntry banEntry = (*it).second;
 589         if(now > banEntry.nBanUntil)
 590         {
 591             setBanned.erase(it++);
 592             setBannedIsDirty = true;
 593             LogPrint("net", "%s: Removed banned node ip/subnet from banlist.dat: %s\n", __func__, subNet.ToString());
 594         }
 595         else
 596             ++it;
 597     }
 598 }
 599
 600 bool CConnman::BannedSetIsDirty()
 601 {
 602     LOCK(cs_setBanned);
 603     return setBannedIsDirty;
 604 }
 605
 606 void CConnman::SetBannedSetDirty(bool dirty)
 607 {
 608     LOCK(cs_setBanned); //reuse setBanned lock for the isDirty flag
 609     setBannedIsDirty = dirty;
 610 }
 611
 612
 613 bool CConnman::IsWhitelistedRange(const CNetAddr &addr) {
 614     LOCK(cs_vWhitelistedRange);
 615     BOOST_FOREACH(const CSubNet& subnet, vWhitelistedRange) {
 616         if (subnet.Match(addr))
 617             return true;
 618     }
 619     return false;
 620 }
 621
 622 void CConnman::AddWhitelistedRange(const CSubNet &subnet) {
 623     LOCK(cs_vWhitelistedRange);
 624     vWhitelistedRange.push_back(subnet);
 625 }
 626
 627 #undef X
 628 #define X(name) stats.name = name
 629 void CNode::copyStats(CNodeStats &stats)
 630 {
 631     stats.nodeid = this->GetId();
 632     X(nServices);
 633     X(fRelayTxes);
 634     X(nLastSend);
 635     X(nLastRecv);
 636     X(nTimeConnected);
 637     X(nTimeOffset);
 638     X(addrName);
 639     X(nVersion);
 640     X(cleanSubVer);
 641     X(fInbound);
 642     X(nStartingHeight);
 643     X(nSendBytes);
 644     X(mapSendBytesPerMsgCmd);
 645     X(nRecvBytes);
 646     X(mapRecvBytesPerMsgCmd);
 647     X(fWhitelisted);
 648
 649     // It is common for nodes with good ping times to suddenly become lagged,
 650     // due to a new block arriving or other large transfer.
 651     // Merely reporting pingtime might fool the caller into thinking the node was still responsive,
 652     // since pingtime does not update until the ping is complete, which might take a while.
 653     // So, if a ping is taking an unusually long time in flight,
 654     // the caller can immediately detect that this is happening.
 655     int64_t nPingUsecWait = 0;
 656     if ((0 != nPingNonceSent) && (0 != nPingUsecStart)) {
 657         nPingUsecWait = GetTimeMicros() - nPingUsecStart;
 658     }
 659
 660     // 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 :)
 661     stats.dPingTime = (((double)nPingUsecTime) / 1e6);
 662     stats.dPingMin  = (((double)nMinPingUsecTime) / 1e6);
 663     stats.dPingWait = (((double)nPingUsecWait) / 1e6);
 664
 665     // Leave string empty if addrLocal invalid (not filled in yet)
 666     stats.addrLocal = addrLocal.IsValid() ? addrLocal.ToString() : "";
 667 }
 668 #undef X
 669
 670 // requires LOCK(cs_vRecvMsg)
 671 bool CNode::ReceiveMsgBytes(const char *pch, unsigned int nBytes, bool& complete)
 672 {
 673     complete = false;
 674     while (nBytes > 0) {
 675
 676         // get current incomplete message, or create a new one
 677         if (vRecvMsg.empty() ||
 678             vRecvMsg.back().complete())
 679             vRecvMsg.push_back(CNetMessage(Params().MessageStart(), SER_NETWORK, nRecvVersion));
 680
 681         CNetMessage& msg = vRecvMsg.back();
 682
 683         // absorb network data
 684         int handled;
 685         if (!msg.in_data)
 686             handled = msg.readHeader(pch, nBytes);
 687         else
 688             handled = msg.readData(pch, nBytes);
 689
 690         if (handled < 0)
 691                 return false;
 692
 693         if (msg.in_data && msg.hdr.nMessageSize > MAX_PROTOCOL_MESSAGE_LENGTH) {
 694             LogPrint("net", "Oversized message from peer=%i, disconnecting\n", GetId());
 695             return false;
 696         }
 697
 698         pch += handled;
 699         nBytes -= handled;
 700
 701         if (msg.complete()) {
 702
 703             //store received bytes per message command
 704             //to prevent a memory DOS, only allow valid commands
 705             mapMsgCmdSize::iterator i = mapRecvBytesPerMsgCmd.find(msg.hdr.pchCommand);
 706             if (i == mapRecvBytesPerMsgCmd.end())
 707                 i = mapRecvBytesPerMsgCmd.find(NET_MESSAGE_COMMAND_OTHER);
 708             assert(i != mapRecvBytesPerMsgCmd.end());
 709             i->second += msg.hdr.nMessageSize + CMessageHeader::HEADER_SIZE;
 710
 711             msg.nTime = GetTimeMicros();
 712             complete = true;
 713         }
 714     }
 715
 716     return true;
 717 }
 718
 719 int CNetMessage::readHeader(const char *pch, unsigned int nBytes)
 720 {
 721     // copy data to temporary parsing buffer
 722     unsigned int nRemaining = 24 - nHdrPos;
 723     unsigned int nCopy = std::min(nRemaining, nBytes);
 724
 725     memcpy(&hdrbuf[nHdrPos], pch, nCopy);
 726     nHdrPos += nCopy;
 727
 728     // if header incomplete, exit
 729     if (nHdrPos < 24)
 730         return nCopy;
 731
 732     // deserialize to CMessageHeader
 733     try {
 734         hdrbuf >> hdr;
 735     }
 736     catch (const std::exception&) {
 737         return -1;
 738     }
 739
 740     // reject messages larger than MAX_SIZE
 741     if (hdr.nMessageSize > MAX_SIZE)
 742             return -1;
 743
 744     // switch state to reading message data
 745     in_data = true;
 746
 747     return nCopy;
 748 }
 749
 750 int CNetMessage::readData(const char *pch, unsigned int nBytes)
 751 {
 752     unsigned int nRemaining = hdr.nMessageSize - nDataPos;
 753     unsigned int nCopy = std::min(nRemaining, nBytes);
 754
 755     if (vRecv.size() < nDataPos + nCopy) {
 756         // Allocate up to 256 KiB ahead, but never more than the total message size.
 757         vRecv.resize(std::min(hdr.nMessageSize, nDataPos + nCopy + 256 * 1024));
 758     }
 759
 760     memcpy(&vRecv[nDataPos], pch, nCopy);
 761     nDataPos += nCopy;
 762
 763     return nCopy;
 764 }
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774 // requires LOCK(cs_vSend)
 775 size_t SocketSendData(CNode *pnode)
 776 {
 777     std::deque<CSerializeData>::iterator it = pnode->vSendMsg.begin();
 778     size_t nSentSize = 0;
 779
 780     while (it != pnode->vSendMsg.end()) {
 781         const CSerializeData &data = *it;
 782         assert(data.size() > pnode->nSendOffset);
 783         int nBytes = send(pnode->hSocket, &data[pnode->nSendOffset], data.size() - pnode->nSendOffset, MSG_NOSIGNAL | MSG_DONTWAIT);
 784         if (nBytes > 0) {
 785             pnode->nLastSend = GetTime();
 786             pnode->nSendBytes += nBytes;
 787             pnode->nSendOffset += nBytes;
 788             nSentSize += nBytes;
 789             if (pnode->nSendOffset == data.size()) {
 790                 pnode->nSendOffset = 0;
 791                 pnode->nSendSize -= data.size();
 792                 it++;
 793             } else {
 794                 // could not send full message; stop sending more
 795                 break;
 796             }
 797         } else {
 798             if (nBytes < 0) {
 799                 // error
 800                 int nErr = WSAGetLastError();
 801                 if (nErr != WSAEWOULDBLOCK && nErr != WSAEMSGSIZE && nErr != WSAEINTR && nErr != WSAEINPROGRESS)
 802                 {
 803                     LogPrintf("socket send error %s\n", NetworkErrorString(nErr));
 804                     pnode->CloseSocketDisconnect();
 805                 }
 806             }
 807             // couldn't send anything at all
 808             break;
 809         }
 810     }
 811
 812     if (it == pnode->vSendMsg.end()) {
 813         assert(pnode->nSendOffset == 0);
 814         assert(pnode->nSendSize == 0);
 815     }
 816     pnode->vSendMsg.erase(pnode->vSendMsg.begin(), it);
 817     return nSentSize;
 818 }
 819
 820 static std::list<CNode*> vNodesDisconnected;
 821
 822 struct NodeEvictionCandidate
 823 {
 824     NodeId id;
 825     int64_t nTimeConnected;
 826     int64_t nMinPingUsecTime;
 827     int64_t nLastBlockTime;
 828     int64_t nLastTXTime;
 829     bool fNetworkNode;
 830     bool fRelayTxes;
 831     bool fBloomFilter;
 832     CAddress addr;
 833     uint64_t nKeyedNetGroup;
 834 };
 835
 836 static bool ReverseCompareNodeMinPingTime(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
 837 {
 838     return a.nMinPingUsecTime > b.nMinPingUsecTime;
 839 }
 840
 841 static bool ReverseCompareNodeTimeConnected(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
 842 {
 843     return a.nTimeConnected > b.nTimeConnected;
 844 }
 845
 846 static bool CompareNetGroupKeyed(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b) {
 847     return a.nKeyedNetGroup < b.nKeyedNetGroup;
 848 }
 849
 850 static bool CompareNodeBlockTime(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
 851 {
 852     // There is a fall-through here because it is common for a node to have many peers which have not yet relayed a block.
 853     if (a.nLastBlockTime != b.nLastBlockTime) return a.nLastBlockTime < b.nLastBlockTime;
 854     if (a.fNetworkNode != b.fNetworkNode) return b.fNetworkNode;
 855     return a.nTimeConnected > b.nTimeConnected;
 856 }
 857
 858 static bool CompareNodeTXTime(const NodeEvictionCandidate &a, const NodeEvictionCandidate &b)
 859 {
 860     // There is a fall-through here because it is common for a node to have more than a few peers that have not yet relayed txn.
 861     if (a.nLastTXTime != b.nLastTXTime) return a.nLastTXTime < b.nLastTXTime;
 862     if (a.fRelayTxes != b.fRelayTxes) return b.fRelayTxes;
 863     if (a.fBloomFilter != b.fBloomFilter) return a.fBloomFilter;
 864     return a.nTimeConnected > b.nTimeConnected;
 865 }
 866
 867 /** Try to find a connection to evict when the node is full.
 868  *  Extreme care must be taken to avoid opening the node to attacker
 869  *   triggered network partitioning.
 870  *  The strategy used here is to protect a small number of peers
 871  *   for each of several distinct characteristics which are difficult
 872  *   to forge.  In order to partition a node the attacker must be
 873  *   simultaneously better at all of them than honest peers.
 874  */
 875 bool CConnman::AttemptToEvictConnection()
 876 {
 877     std::vector<NodeEvictionCandidate> vEvictionCandidates;
 878     {
 879         LOCK(cs_vNodes);
 880
 881         BOOST_FOREACH(CNode *node, vNodes) {
 882             if (node->fWhitelisted)
 883                 continue;
 884             if (!node->fInbound)
 885                 continue;
 886             if (node->fDisconnect)
 887                 continue;
 888             NodeEvictionCandidate candidate = {node->id, node->nTimeConnected, node->nMinPingUsecTime,
 889                                                node->nLastBlockTime, node->nLastTXTime, node->fNetworkNode,
 890                                                node->fRelayTxes, node->pfilter != NULL, node->addr, node->nKeyedNetGroup};
 891             vEvictionCandidates.push_back(candidate);
 892         }
 893     }
 894
 895     if (vEvictionCandidates.empty()) return false;
 896
 897     // Protect connections with certain characteristics
 898
 899     // Deterministically select 4 peers to protect by netgroup.
 900     // An attacker cannot predict which netgroups will be protected
 901     std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), CompareNetGroupKeyed);
 902     vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(4, static_cast<int>(vEvictionCandidates.size())), vEvictionCandidates.end());
 903
 904     if (vEvictionCandidates.empty()) return false;
 905
 906     // Protect the 8 nodes with the lowest minimum ping time.
 907     // An attacker cannot manipulate this metric without physically moving nodes closer to the target.
 908     std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), ReverseCompareNodeMinPingTime);
 909     vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(8, static_cast<int>(vEvictionCandidates.size())), vEvictionCandidates.end());
 910
 911     if (vEvictionCandidates.empty()) return false;
 912
 913     // Protect 4 nodes that most recently sent us transactions.
 914     // An attacker cannot manipulate this metric without performing useful work.
 915     std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), CompareNodeTXTime);
 916     vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(4, static_cast<int>(vEvictionCandidates.size())), vEvictionCandidates.end());
 917
 918     if (vEvictionCandidates.empty()) return false;
 919
 920     // Protect 4 nodes that most recently sent us blocks.
 921     // An attacker cannot manipulate this metric without performing useful work.
 922     std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), CompareNodeBlockTime);
 923     vEvictionCandidates.erase(vEvictionCandidates.end() - std::min(4, static_cast<int>(vEvictionCandidates.size())), vEvictionCandidates.end());
 924
 925     if (vEvictionCandidates.empty()) return false;
 926
 927     // Protect the half of the remaining nodes which have been connected the longest.
 928     // This replicates the non-eviction implicit behavior, and precludes attacks that start later.
 929     std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), ReverseCompareNodeTimeConnected);
 930     vEvictionCandidates.erase(vEvictionCandidates.end() - static_cast<int>(vEvictionCandidates.size() / 2), vEvictionCandidates.end());
 931
 932     if (vEvictionCandidates.empty()) return false;
 933
 934     // Identify the network group with the most connections and youngest member.
 935     // (vEvictionCandidates is already sorted by reverse connect time)
 936     uint64_t naMostConnections;
 937     unsigned int nMostConnections = 0;
 938     int64_t nMostConnectionsTime = 0;
 939     std::map<uint64_t, std::vector<NodeEvictionCandidate> > mapNetGroupNodes;
 940     BOOST_FOREACH(const NodeEvictionCandidate &node, vEvictionCandidates) {
 941         mapNetGroupNodes[node.nKeyedNetGroup].push_back(node);
 942         int64_t grouptime = mapNetGroupNodes[node.nKeyedNetGroup][0].nTimeConnected;
 943         size_t groupsize = mapNetGroupNodes[node.nKeyedNetGroup].size();
 944
 945         if (groupsize > nMostConnections || (groupsize == nMostConnections && grouptime > nMostConnectionsTime)) {
 946             nMostConnections = groupsize;
 947             nMostConnectionsTime = grouptime;
 948             naMostConnections = node.nKeyedNetGroup;
 949         }
 950     }
 951
 952     // Reduce to the network group with the most connections
 953     vEvictionCandidates = std::move(mapNetGroupNodes[naMostConnections]);
 954
 955     // Disconnect from the network group with the most connections
 956     NodeId evicted = vEvictionCandidates.front().id;
 957     LOCK(cs_vNodes);
 958     for(std::vector<CNode*>::const_iterator it(vNodes.begin()); it != vNodes.end(); ++it) {
 959         if ((*it)->GetId() == evicted) {
 960             (*it)->fDisconnect = true;
 961             return true;
 962         }
 963     }
 964     return false;
 965 }
 966
 967 void CConnman::AcceptConnection(const ListenSocket& hListenSocket) {
 968     struct sockaddr_storage sockaddr;
 969     socklen_t len = sizeof(sockaddr);
 970     SOCKET hSocket = accept(hListenSocket.socket, (struct sockaddr*)&sockaddr, &len);
 971     CAddress addr;
 972     int nInbound = 0;
 973     int nMaxInbound = nMaxConnections - (nMaxOutbound + MAX_FEELER_CONNECTIONS);
 974     assert(nMaxInbound > 0);
 975
 976     if (hSocket != INVALID_SOCKET)
 977         if (!addr.SetSockAddr((const struct sockaddr*)&sockaddr))
 978             LogPrintf("Warning: Unknown socket family\n");
 979
 980     bool whitelisted = hListenSocket.whitelisted || IsWhitelistedRange(addr);
 981     {
 982         LOCK(cs_vNodes);
 983         BOOST_FOREACH(CNode* pnode, vNodes)
 984             if (pnode->fInbound)
 985                 nInbound++;
 986     }
 987
 988     if (hSocket == INVALID_SOCKET)
 989     {
 990         int nErr = WSAGetLastError();
 991         if (nErr != WSAEWOULDBLOCK)
 992             LogPrintf("socket error accept failed: %s\n", NetworkErrorString(nErr));
 993         return;
 994     }
 995
 996     if (!IsSelectableSocket(hSocket))
 997     {
 998         LogPrintf("connection from %s dropped: non-selectable socket\n", addr.ToString());
 999         CloseSocket(hSocket);
1000         return;
1001     }
1002
1003     // According to the internet TCP_NODELAY is not carried into accepted sockets
1004     // on all platforms.  Set it again here just to be sure.
1005     int set = 1;
1006 #ifdef WIN32
1007     setsockopt(hSocket, IPPROTO_TCP, TCP_NODELAY, (const char*)&set, sizeof(int));
1008 #else
1009     setsockopt(hSocket, IPPROTO_TCP, TCP_NODELAY, (void*)&set, sizeof(int));
1010 #endif
1011
1012     if (IsBanned(addr) && !whitelisted)
1013     {
1014         LogPrintf("connection from %s dropped (banned)\n", addr.ToString());
1015         CloseSocket(hSocket);
1016         return;
1017     }
1018
1019     if (nInbound >= nMaxInbound)
1020     {
1021         if (!AttemptToEvictConnection()) {
1022             // No connection to evict, disconnect the new connection
1023             LogPrint("net", "failed to find an eviction candidate - connection dropped (full)\n");
1024             CloseSocket(hSocket);
1025             return;
1026         }
1027     }
1028
1029     CNode* pnode = new CNode(GetNewNodeId(), nLocalServices, GetBestHeight(), hSocket, addr, "", true);
1030     GetNodeSignals().InitializeNode(pnode->GetId(), pnode);
1031     pnode->AddRef();
1032     pnode->fWhitelisted = whitelisted;
1033
1034     LogPrint("net", "connection from %s accepted\n", addr.ToString());
1035
1036     {
1037         LOCK(cs_vNodes);
1038         vNodes.push_back(pnode);
1039     }
1040 }
1041
1042 void CConnman::ThreadSocketHandler()
1043 {
1044     unsigned int nPrevNodeCount = 0;
1045     while (true)
1046     {
1047         //
1048         // Disconnect nodes
1049         //
1050         {
1051             LOCK(cs_vNodes);
1052             // Disconnect unused nodes
1053             std::vector<CNode*> vNodesCopy = vNodes;
1054             BOOST_FOREACH(CNode* pnode, vNodesCopy)
1055             {
1056                 if (pnode->fDisconnect ||
1057                     (pnode->GetRefCount() <= 0 && pnode->vRecvMsg.empty() && pnode->nSendSize == 0 && pnode->ssSend.empty()))
1058                 {
1059                     // remove from vNodes
1060                     vNodes.erase(remove(vNodes.begin(), vNodes.end(), pnode), vNodes.end());
1061
1062                     // release outbound grant (if any)
1063                     pnode->grantOutbound.Release();
1064
1065                     // close socket and cleanup
1066                     pnode->CloseSocketDisconnect();
1067
1068                     // hold in disconnected pool until all refs are released
1069                     if (pnode->fNetworkNode || pnode->fInbound)
1070                         pnode->Release();
1071                     vNodesDisconnected.push_back(pnode);
1072                 }
1073             }
1074         }
1075         {
1076             // Delete disconnected nodes
1077             std::list<CNode*> vNodesDisconnectedCopy = vNodesDisconnected;
1078             BOOST_FOREACH(CNode* pnode, vNodesDisconnectedCopy)
1079             {
1080                 // wait until threads are done using it
1081                 if (pnode->GetRefCount() <= 0)
1082                 {
1083                     bool fDelete = false;
1084                     {
1085                         TRY_LOCK(pnode->cs_vSend, lockSend);
1086                         if (lockSend)
1087                         {
1088                             TRY_LOCK(pnode->cs_vRecvMsg, lockRecv);
1089                             if (lockRecv)
1090                             {
1091                                 TRY_LOCK(pnode->cs_inventory, lockInv);
1092                                 if (lockInv)
1093                                     fDelete = true;
1094                             }
1095                         }
1096                     }
1097                     if (fDelete)
1098                     {
1099                         vNodesDisconnected.remove(pnode);
1100                         DeleteNode(pnode);
1101                     }
1102                 }
1103             }
1104         }
1105         if(vNodes.size() != nPrevNodeCount) {
1106             nPrevNodeCount = vNodes.size();
1107             uiInterface.NotifyNumConnectionsChanged(nPrevNodeCount);
1108         }
1109
1110         //
1111         // Find which sockets have data to receive
1112         //
1113         struct timeval timeout;
1114         timeout.tv_sec  = 0;
1115         timeout.tv_usec = 50000; // frequency to poll pnode->vSend
1116
1117         fd_set fdsetRecv;
1118         fd_set fdsetSend;
1119         fd_set fdsetError;
1120         FD_ZERO(&fdsetRecv);
1121         FD_ZERO(&fdsetSend);
1122         FD_ZERO(&fdsetError);
1123         SOCKET hSocketMax = 0;
1124         bool have_fds = false;
1125
1126         BOOST_FOREACH(const ListenSocket& hListenSocket, vhListenSocket) {
1127             FD_SET(hListenSocket.socket, &fdsetRecv);
1128             hSocketMax = std::max(hSocketMax, hListenSocket.socket);
1129             have_fds = true;
1130         }
1131
1132         {
1133             LOCK(cs_vNodes);
1134             BOOST_FOREACH(CNode* pnode, vNodes)
1135             {
1136                 if (pnode->hSocket == INVALID_SOCKET)
1137                     continue;
1138                 FD_SET(pnode->hSocket, &fdsetError);
1139                 hSocketMax = std::max(hSocketMax, pnode->hSocket);
1140                 have_fds = true;
1141
1142                 // Implement the following logic:
1143                 // * If there is data to send, select() for sending data. As this only
1144                 //   happens when optimistic write failed, we choose to first drain the
1145                 //   write buffer in this case before receiving more. This avoids
1146                 //   needlessly queueing received data, if the remote peer is not themselves
1147                 //   receiving data. This means properly utilizing TCP flow control signalling.
1148                 // * Otherwise, if there is no (complete) message in the receive buffer,
1149                 //   or there is space left in the buffer, select() for receiving data.
1150                 // * (if neither of the above applies, there is certainly one message
1151                 //   in the receiver buffer ready to be processed).
1152                 // Together, that means that at least one of the following is always possible,
1153                 // so we don't deadlock:
1154                 // * We send some data.
1155                 // * We wait for data to be received (and disconnect after timeout).
1156                 // * We process a message in the buffer (message handler thread).
1157                 {
1158                     TRY_LOCK(pnode->cs_vSend, lockSend);
1159                     if (lockSend) {
1160                         if (pnode->nOptimisticBytesWritten) {
1161                             RecordBytesSent(pnode->nOptimisticBytesWritten);
1162                             pnode->nOptimisticBytesWritten = 0;
1163                         }
1164                         if (!pnode->vSendMsg.empty()) {
1165                             FD_SET(pnode->hSocket, &fdsetSend);
1166                             continue;
1167                         }
1168                     }
1169                 }
1170                 {
1171                     TRY_LOCK(pnode->cs_vRecvMsg, lockRecv);
1172                     if (lockRecv && (
1173                         pnode->vRecvMsg.empty() || !pnode->vRecvMsg.front().complete() ||
1174                         pnode->GetTotalRecvSize() <= GetReceiveFloodSize()))
1175                         FD_SET(pnode->hSocket, &fdsetRecv);
1176                 }
1177             }
1178         }
1179
1180         int nSelect = select(have_fds ? hSocketMax + 1 : 0,
1181                              &fdsetRecv, &fdsetSend, &fdsetError, &timeout);
1182         boost::this_thread::interruption_point();
1183
1184         if (nSelect == SOCKET_ERROR)
1185         {
1186             if (have_fds)
1187             {
1188                 int nErr = WSAGetLastError();
1189                 LogPrintf("socket select error %s\n", NetworkErrorString(nErr));
1190                 for (unsigned int i = 0; i <= hSocketMax; i++)
1191                     FD_SET(i, &fdsetRecv);
1192             }
1193             FD_ZERO(&fdsetSend);
1194             FD_ZERO(&fdsetError);
1195             MilliSleep(timeout.tv_usec/1000);
1196         }
1197
1198         //
1199         // Accept new connections
1200         //
1201         BOOST_FOREACH(const ListenSocket& hListenSocket, vhListenSocket)
1202         {
1203             if (hListenSocket.socket != INVALID_SOCKET && FD_ISSET(hListenSocket.socket, &fdsetRecv))
1204             {
1205                 AcceptConnection(hListenSocket);
1206             }
1207         }
1208
1209         //
1210         // Service each socket
1211         //
1212         std::vector<CNode*> vNodesCopy;
1213         {
1214             LOCK(cs_vNodes);
1215             vNodesCopy = vNodes;
1216             BOOST_FOREACH(CNode* pnode, vNodesCopy)
1217                 pnode->AddRef();
1218         }
1219         BOOST_FOREACH(CNode* pnode, vNodesCopy)
1220         {
1221             boost::this_thread::interruption_point();
1222
1223             //
1224             // Receive
1225             //
1226             if (pnode->hSocket == INVALID_SOCKET)
1227                 continue;
1228             if (FD_ISSET(pnode->hSocket, &fdsetRecv) || FD_ISSET(pnode->hSocket, &fdsetError))
1229             {
1230                 TRY_LOCK(pnode->cs_vRecvMsg, lockRecv);
1231                 if (lockRecv)
1232                 {
1233                     {
1234                         // typical socket buffer is 8K-64K
1235                         char pchBuf[0x10000];
1236                         int nBytes = recv(pnode->hSocket, pchBuf, sizeof(pchBuf), MSG_DONTWAIT);
1237                         if (nBytes > 0)
1238                         {
1239                             bool notify = false;
1240                             if (!pnode->ReceiveMsgBytes(pchBuf, nBytes, notify))
1241                                 pnode->CloseSocketDisconnect();
1242                             if(notify)
1243                                 messageHandlerCondition.notify_one();
1244                             pnode->nLastRecv = GetTime();
1245                             pnode->nRecvBytes += nBytes;
1246                             RecordBytesRecv(nBytes);
1247                         }
1248                         else if (nBytes == 0)
1249                         {
1250                             // socket closed gracefully
1251                             if (!pnode->fDisconnect)
1252                                 LogPrint("net", "socket closed\n");
1253                             pnode->CloseSocketDisconnect();
1254                         }
1255                         else if (nBytes < 0)
1256                         {
1257                             // error
1258                             int nErr = WSAGetLastError();
1259                             if (nErr != WSAEWOULDBLOCK && nErr != WSAEMSGSIZE && nErr != WSAEINTR && nErr != WSAEINPROGRESS)
1260                             {
1261                                 if (!pnode->fDisconnect)
1262                                     LogPrintf("socket recv error %s\n", NetworkErrorString(nErr));
1263                                 pnode->CloseSocketDisconnect();
1264                             }
1265                         }
1266                     }
1267                 }
1268             }
1269
1270             //
1271             // Send
1272             //
1273             if (pnode->hSocket == INVALID_SOCKET)
1274                 continue;
1275             if (FD_ISSET(pnode->hSocket, &fdsetSend))
1276             {
1277                 TRY_LOCK(pnode->cs_vSend, lockSend);
1278                 if (lockSend) {
1279                     size_t nBytes = SocketSendData(pnode);
1280                     if (nBytes)
1281                         RecordBytesSent(nBytes);
1282                 }
1283             }
1284
1285             //
1286             // Inactivity checking
1287             //
1288             int64_t nTime = GetTime();
1289             if (nTime - pnode->nTimeConnected > 60)
1290             {
1291                 if (pnode->nLastRecv == 0 || pnode->nLastSend == 0)
1292                 {
1293                     LogPrint("net", "socket no message in first 60 seconds, %d %d from %d\n", pnode->nLastRecv != 0, pnode->nLastSend != 0, pnode->id);
1294                     pnode->fDisconnect = true;
1295                 }
1296                 else if (nTime - pnode->nLastSend > TIMEOUT_INTERVAL)
1297                 {
1298                     LogPrintf("socket sending timeout: %is\n", nTime - pnode->nLastSend);
1299                     pnode->fDisconnect = true;
1300                 }
1301                 else if (nTime - pnode->nLastRecv > (pnode->nVersion > BIP0031_VERSION ? TIMEOUT_INTERVAL : 90*60))
1302                 {
1303                     LogPrintf("socket receive timeout: %is\n", nTime - pnode->nLastRecv);
1304                     pnode->fDisconnect = true;
1305                 }
1306                 else if (pnode->nPingNonceSent && pnode->nPingUsecStart + TIMEOUT_INTERVAL * 1000000 < GetTimeMicros())
1307                 {
1308                     LogPrintf("ping timeout: %fs\n", 0.000001 * (GetTimeMicros() - pnode->nPingUsecStart));
1309                     pnode->fDisconnect = true;
1310                 }
1311             }
1312         }
1313         {
1314             LOCK(cs_vNodes);
1315             BOOST_FOREACH(CNode* pnode, vNodesCopy)
1316                 pnode->Release();
1317         }
1318     }
1319 }
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329 #ifdef USE_UPNP
1330 void ThreadMapPort()
1331 {
1332     std::string port = strprintf("%u", GetListenPort());
1333     const char * multicastif = 0;
1334     const char * minissdpdpath = 0;
1335     struct UPNPDev * devlist = 0;
1336     char lanaddr[64];
1337
1338 #ifndef UPNPDISCOVER_SUCCESS
1339     /* miniupnpc 1.5 */
1340     devlist = upnpDiscover(2000, multicastif, minissdpdpath, 0);
1341 #elif MINIUPNPC_API_VERSION < 14
1342     /* miniupnpc 1.6 */
1343     int error = 0;
1344     devlist = upnpDiscover(2000, multicastif, minissdpdpath, 0, 0, &error);
1345 #else
1346     /* miniupnpc 1.9.20150730 */
1347     int error = 0;
1348     devlist = upnpDiscover(2000, multicastif, minissdpdpath, 0, 0, 2, &error);
1349 #endif
1350
1351     struct UPNPUrls urls;
1352     struct IGDdatas data;
1353     int r;
1354
1355     r = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr));
1356     if (r == 1)
1357     {
1358         if (fDiscover) {
1359             char externalIPAddress[40];
1360             r = UPNP_GetExternalIPAddress(urls.controlURL, data.first.servicetype, externalIPAddress);
1361             if(r != UPNPCOMMAND_SUCCESS)
1362                 LogPrintf("UPnP: GetExternalIPAddress() returned %d\n", r);
1363             else
1364             {
1365                 if(externalIPAddress[0])
1366                 {
1367                     CNetAddr resolved;
1368                     if(LookupHost(externalIPAddress, resolved, false)) {
1369                         LogPrintf("UPnP: ExternalIPAddress = %s\n", resolved.ToString().c_str());
1370                         AddLocal(resolved, LOCAL_UPNP);
1371                     }
1372                 }
1373                 else
1374                     LogPrintf("UPnP: GetExternalIPAddress failed.\n");
1375             }
1376         }
1377
1378         std::string strDesc = "Bitcoin " + FormatFullVersion();
1379
1380         try {
1381             while (true) {
1382 #ifndef UPNPDISCOVER_SUCCESS
1383                 /* miniupnpc 1.5 */
1384                 r = UPNP_AddPortMapping(urls.controlURL, data.first.servicetype,
1385                                     port.c_str(), port.c_str(), lanaddr, strDesc.c_str(), "TCP", 0);
1386 #else
1387                 /* miniupnpc 1.6 */
1388                 r = UPNP_AddPortMapping(urls.controlURL, data.first.servicetype,
1389                                     port.c_str(), port.c_str(), lanaddr, strDesc.c_str(), "TCP", 0, "0");
1390 #endif
1391
1392                 if(r!=UPNPCOMMAND_SUCCESS)
1393                     LogPrintf("AddPortMapping(%s, %s, %s) failed with code %d (%s)\n",
1394                         port, port, lanaddr, r, strupnperror(r));
1395                 else
1396                     LogPrintf("UPnP Port Mapping successful.\n");
1397
1398                 MilliSleep(20*60*1000); // Refresh every 20 minutes
1399             }
1400         }
1401         catch (const boost::thread_interrupted&)
1402         {
1403             r = UPNP_DeletePortMapping(urls.controlURL, data.first.servicetype, port.c_str(), "TCP", 0);
1404             LogPrintf("UPNP_DeletePortMapping() returned: %d\n", r);
1405             freeUPNPDevlist(devlist); devlist = 0;
1406             FreeUPNPUrls(&urls);
1407             throw;
1408         }
1409     } else {
1410         LogPrintf("No valid UPnP IGDs found\n");
1411         freeUPNPDevlist(devlist); devlist = 0;
1412         if (r != 0)
1413             FreeUPNPUrls(&urls);
1414     }
1415 }
1416
1417 void MapPort(bool fUseUPnP)
1418 {
1419     static boost::thread* upnp_thread = NULL;
1420
1421     if (fUseUPnP)
1422     {
1423         if (upnp_thread) {
1424             upnp_thread->interrupt();
1425             upnp_thread->join();
1426             delete upnp_thread;
1427         }
1428         upnp_thread = new boost::thread(boost::bind(&TraceThread<void (*)()>, "upnp", &ThreadMapPort));
1429     }
1430     else if (upnp_thread) {
1431         upnp_thread->interrupt();
1432         upnp_thread->join();
1433         delete upnp_thread;
1434         upnp_thread = NULL;
1435     }
1436 }
1437
1438 #else
1439 void MapPort(bool)
1440 {
1441     // Intentionally left blank.
1442 }
1443 #endif
1444
1445
1446
1447
1448
1449
1450 static std::string GetDNSHost(const CDNSSeedData& data, ServiceFlags* requiredServiceBits)
1451 {
1452     //use default host for non-filter-capable seeds or if we use the default service bits (NODE_NETWORK)
1453     if (!data.supportsServiceBitsFiltering || *requiredServiceBits == NODE_NETWORK) {
1454         *requiredServiceBits = NODE_NETWORK;
1455         return data.host;
1456     }
1457
1458     return strprintf("x%x.%s", *requiredServiceBits, data.host);
1459 }
1460
1461
1462 void CConnman::ThreadDNSAddressSeed()
1463 {
1464     // goal: only query DNS seeds if address need is acute
1465     if ((addrman.size() > 0) &&
1466         (!GetBoolArg("-forcednsseed", DEFAULT_FORCEDNSSEED))) {
1467         MilliSleep(11 * 1000);
1468
1469         LOCK(cs_vNodes);
1470         if (vNodes.size() >= 2) {
1471             LogPrintf("P2P peers available. Skipped DNS seeding.\n");
1472             return;
1473         }
1474     }
1475
1476     const std::vector<CDNSSeedData> &vSeeds = Params().DNSSeeds();
1477     int found = 0;
1478
1479     LogPrintf("Loading addresses from DNS seeds (could take a while)\n");
1480
1481     BOOST_FOREACH(const CDNSSeedData &seed, vSeeds) {
1482         if (HaveNameProxy()) {
1483             AddOneShot(seed.host);
1484         } else {
1485             std::vector<CNetAddr> vIPs;
1486             std::vector<CAddress> vAdd;
1487             ServiceFlags requiredServiceBits = nRelevantServices;
1488             if (LookupHost(GetDNSHost(seed, &requiredServiceBits).c_str(), vIPs, 0, true))
1489             {
1490                 BOOST_FOREACH(const CNetAddr& ip, vIPs)
1491                 {
1492                     int nOneDay = 24*3600;
1493                     CAddress addr = CAddress(CService(ip, Params().GetDefaultPort()), requiredServiceBits);
1494                     addr.nTime = GetTime() - 3*nOneDay - GetRand(4*nOneDay); // use a random age between 3 and 7 days old
1495                     vAdd.push_back(addr);
1496                     found++;
1497                 }
1498             }
1499             // TODO: The seed name resolve may fail, yielding an IP of [::], which results in
1500             // addrman assigning the same source to results from different seeds.
1501             // This should switch to a hard-coded stable dummy IP for each seed name, so that the
1502             // resolve is not required at all.
1503             if (!vIPs.empty()) {
1504                 CService seedSource;
1505                 Lookup(seed.name.c_str(), seedSource, 0, true);
1506                 addrman.Add(vAdd, seedSource);
1507             }
1508         }
1509     }
1510
1511     LogPrintf("%d addresses found from DNS seeds\n", found);
1512 }
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525 void CConnman::DumpAddresses()
1526 {
1527     int64_t nStart = GetTimeMillis();
1528
1529     CAddrDB adb;
1530     adb.Write(addrman);
1531
1532     LogPrint("net", "Flushed %d addresses to peers.dat  %dms\n",
1533            addrman.size(), GetTimeMillis() - nStart);
1534 }
1535
1536 void CConnman::DumpData()
1537 {
1538     DumpAddresses();
1539     DumpBanlist();
1540 }
1541
1542 void CConnman::ProcessOneShot()
1543 {
1544     std::string strDest;
1545     {
1546         LOCK(cs_vOneShots);
1547         if (vOneShots.empty())
1548             return;
1549         strDest = vOneShots.front();
1550         vOneShots.pop_front();
1551     }
1552     CAddress addr;
1553     CSemaphoreGrant grant(*semOutbound, true);
1554     if (grant) {
1555         if (!OpenNetworkConnection(addr, false, &grant, strDest.c_str(), true))
1556             AddOneShot(strDest);
1557     }
1558 }
1559
1560 void CConnman::ThreadOpenConnections()
1561 {
1562     // Connect to specific addresses
1563     if (mapArgs.count("-connect") && mapMultiArgs["-connect"].size() > 0)
1564     {
1565         for (int64_t nLoop = 0;; nLoop++)
1566         {
1567             ProcessOneShot();
1568             BOOST_FOREACH(const std::string& strAddr, mapMultiArgs["-connect"])
1569             {
1570                 CAddress addr(CService(), NODE_NONE);
1571                 OpenNetworkConnection(addr, false, NULL, strAddr.c_str());
1572                 for (int i = 0; i < 10 && i < nLoop; i++)
1573                 {
1574                     MilliSleep(500);
1575                 }
1576             }
1577             MilliSleep(500);
1578         }
1579     }
1580
1581     // Initiate network connections
1582     int64_t nStart = GetTime();
1583
1584     // Minimum time before next feeler connection (in microseconds).
1585     int64_t nNextFeeler = PoissonNextSend(nStart*1000*1000, FEELER_INTERVAL);
1586     while (true)
1587     {
1588         ProcessOneShot();
1589
1590         MilliSleep(500);
1591
1592         CSemaphoreGrant grant(*semOutbound);
1593         boost::this_thread::interruption_point();
1594
1595         // Add seed nodes if DNS seeds are all down (an infrastructure attack?).
1596         if (addrman.size() == 0 && (GetTime() - nStart > 60)) {
1597             static bool done = false;
1598             if (!done) {
1599                 LogPrintf("Adding fixed seed nodes as DNS doesn't seem to be available.\n");
1600                 CNetAddr local;
1601                 LookupHost("127.0.0.1", local, false);
1602                 addrman.Add(convertSeed6(Params().FixedSeeds()), local);
1603                 done = true;
1604             }
1605         }
1606
1607         //
1608         // Choose an address to connect to based on most recently seen
1609         //
1610         CAddress addrConnect;
1611
1612         // Only connect out to one peer per network group (/16 for IPv4).
1613         // Do this here so we don't have to critsect vNodes inside mapAddresses critsect.
1614         int nOutbound = 0;
1615         std::set<std::vector<unsigned char> > setConnected;
1616         {
1617             LOCK(cs_vNodes);
1618             BOOST_FOREACH(CNode* pnode, vNodes) {
1619                 if (!pnode->fInbound) {
1620                     setConnected.insert(pnode->addr.GetGroup());
1621                     nOutbound++;
1622                 }
1623             }
1624         }
1625         assert(nOutbound <= (nMaxOutbound + MAX_FEELER_CONNECTIONS));
1626
1627         // Feeler Connections
1628         //
1629         // Design goals:
1630         //  * Increase the number of connectable addresses in the tried table.
1631         //
1632         // Method:
1633         //  * Choose a random address from new and attempt to connect to it if we can connect
1634         //    successfully it is added to tried.
1635         //  * Start attempting feeler connections only after node finishes making outbound
1636         //    connections.
1637         //  * Only make a feeler connection once every few minutes.
1638         //
1639         bool fFeeler = false;
1640         if (nOutbound >= nMaxOutbound) {
1641             int64_t nTime = GetTimeMicros(); // The current time right now (in microseconds).
1642             if (nTime > nNextFeeler) {
1643                 nNextFeeler = PoissonNextSend(nTime, FEELER_INTERVAL);
1644                 fFeeler = true;
1645             } else {
1646                 continue;
1647             }
1648         }
1649
1650         int64_t nANow = GetAdjustedTime();
1651         int nTries = 0;
1652         while (true)
1653         {
1654             CAddrInfo addr = addrman.Select(fFeeler);
1655
1656             // if we selected an invalid address, restart
1657             if (!addr.IsValid() || setConnected.count(addr.GetGroup()) || IsLocal(addr))
1658                 break;
1659
1660             // If we didn't find an appropriate destination after trying 100 addresses fetched from addrman,
1661             // stop this loop, and let the outer loop run again (which sleeps, adds seed nodes, recalculates
1662             // already-connected network ranges, ...) before trying new addrman addresses.
1663             nTries++;
1664             if (nTries > 100)
1665                 break;
1666
1667             if (IsLimited(addr))
1668                 continue;
1669
1670             // only connect to full nodes
1671             if ((addr.nServices & REQUIRED_SERVICES) != REQUIRED_SERVICES)
1672                 continue;
1673
1674             // only consider very recently tried nodes after 30 failed attempts
1675             if (nANow - addr.nLastTry < 600 && nTries < 30)
1676                 continue;
1677
1678             // only consider nodes missing relevant services after 40 failed attempts
1679             if ((addr.nServices & nRelevantServices) != nRelevantServices && nTries < 40)
1680                 continue;
1681
1682             // do not allow non-default ports, unless after 50 invalid addresses selected already
1683             if (addr.GetPort() != Params().GetDefaultPort() && nTries < 50)
1684                 continue;
1685
1686             addrConnect = addr;
1687             break;
1688         }
1689
1690         if (addrConnect.IsValid()) {
1691
1692             if (fFeeler) {
1693                 // Add small amount of random noise before connection to avoid synchronization.
1694                 int randsleep = GetRandInt(FEELER_SLEEP_WINDOW * 1000);
1695                 MilliSleep(randsleep);
1696                 LogPrint("net", "Making feeler connection to %s\n", addrConnect.ToString());
1697             }
1698
1699             OpenNetworkConnection(addrConnect, (int)setConnected.size() >= std::min(nMaxConnections - 1, 2), &grant, NULL, false, fFeeler);
1700         }
1701     }
1702 }
1703
1704 std::vector<AddedNodeInfo> CConnman::GetAddedNodeInfo()
1705 {
1706     std::vector<AddedNodeInfo> ret;
1707
1708     std::list<std::string> lAddresses(0);
1709     {
1710         LOCK(cs_vAddedNodes);
1711         ret.reserve(vAddedNodes.size());
1712         BOOST_FOREACH(const std::string& strAddNode, vAddedNodes)
1713             lAddresses.push_back(strAddNode);
1714     }
1715
1716
1717     // Build a map of all already connected addresses (by IP:port and by name) to inbound/outbound and resolved CService
1718     std::map<CService, bool> mapConnected;
1719     std::map<std::string, std::pair<bool, CService>> mapConnectedByName;
1720     {
1721         LOCK(cs_vNodes);
1722         for (const CNode* pnode : vNodes) {
1723             if (pnode->addr.IsValid()) {
1724                 mapConnected[pnode->addr] = pnode->fInbound;
1725             }
1726             if (!pnode->addrName.empty()) {
1727                 mapConnectedByName[pnode->addrName] = std::make_pair(pnode->fInbound, static_cast<const CService&>(pnode->addr));
1728             }
1729         }
1730     }
1731
1732     BOOST_FOREACH(const std::string& strAddNode, lAddresses) {
1733         CService service(LookupNumeric(strAddNode.c_str(), Params().GetDefaultPort()));
1734         if (service.IsValid()) {
1735             // strAddNode is an IP:port
1736             auto it = mapConnected.find(service);
1737             if (it != mapConnected.end()) {
1738                 ret.push_back(AddedNodeInfo{strAddNode, service, true, it->second});
1739             } else {
1740                 ret.push_back(AddedNodeInfo{strAddNode, CService(), false, false});
1741             }
1742         } else {
1743             // strAddNode is a name
1744             auto it = mapConnectedByName.find(strAddNode);
1745             if (it != mapConnectedByName.end()) {
1746                 ret.push_back(AddedNodeInfo{strAddNode, it->second.second, true, it->second.first});
1747             } else {
1748                 ret.push_back(AddedNodeInfo{strAddNode, CService(), false, false});
1749             }
1750         }
1751     }
1752
1753     return ret;
1754 }
1755
1756 void CConnman::ThreadOpenAddedConnections()
1757 {
1758     {
1759         LOCK(cs_vAddedNodes);
1760         vAddedNodes = mapMultiArgs["-addnode"];
1761     }
1762
1763     for (unsigned int i = 0; true; i++)
1764     {
1765         std::vector<AddedNodeInfo> vInfo = GetAddedNodeInfo();
1766         for (const AddedNodeInfo& info : vInfo) {
1767             if (!info.fConnected) {
1768                 CSemaphoreGrant grant(*semOutbound);
1769                 // If strAddedNode is an IP/port, decode it immediately, so
1770                 // OpenNetworkConnection can detect existing connections to that IP/port.
1771                 CService service(LookupNumeric(info.strAddedNode.c_str(), Params().GetDefaultPort()));
1772                 OpenNetworkConnection(CAddress(service, NODE_NONE), false, &grant, info.strAddedNode.c_str(), false);
1773                 MilliSleep(500);
1774             }
1775         }
1776
1777         MilliSleep(120000); // Retry every 2 minutes
1778     }
1779 }
1780
1781 // if successful, this moves the passed grant to the constructed node
1782 bool CConnman::OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound, const char *pszDest, bool fOneShot, bool fFeeler)
1783 {
1784     //
1785     // Initiate outbound network connection
1786     //
1787     boost::this_thread::interruption_point();
1788     if (!pszDest) {
1789         if (IsLocal(addrConnect) ||
1790             FindNode((CNetAddr)addrConnect) || IsBanned(addrConnect) ||
1791             FindNode(addrConnect.ToStringIPPort()))
1792             return false;
1793     } else if (FindNode(std::string(pszDest)))
1794         return false;
1795
1796     CNode* pnode = ConnectNode(addrConnect, pszDest, fCountFailure);
1797     boost::this_thread::interruption_point();
1798
1799     if (!pnode)
1800         return false;
1801     if (grantOutbound)
1802         grantOutbound->MoveTo(pnode->grantOutbound);
1803     pnode->fNetworkNode = true;
1804     if (fOneShot)
1805         pnode->fOneShot = true;
1806     if (fFeeler)
1807         pnode->fFeeler = true;
1808
1809     return true;
1810 }
1811
1812
1813 void CConnman::ThreadMessageHandler()
1814 {
1815     boost::mutex condition_mutex;
1816     boost::unique_lock<boost::mutex> lock(condition_mutex);
1817
1818     while (true)
1819     {
1820         std::vector<CNode*> vNodesCopy;
1821         {
1822             LOCK(cs_vNodes);
1823             vNodesCopy = vNodes;
1824             BOOST_FOREACH(CNode* pnode, vNodesCopy) {
1825                 pnode->AddRef();
1826             }
1827         }
1828
1829         bool fSleep = true;
1830
1831         BOOST_FOREACH(CNode* pnode, vNodesCopy)
1832         {
1833             if (pnode->fDisconnect)
1834                 continue;
1835
1836             // Receive messages
1837             {
1838                 TRY_LOCK(pnode->cs_vRecvMsg, lockRecv);
1839                 if (lockRecv)
1840                 {
1841                     if (!GetNodeSignals().ProcessMessages(pnode, *this))
1842                         pnode->CloseSocketDisconnect();
1843
1844                     if (pnode->nSendSize < GetSendBufferSize())
1845                     {
1846                         if (!pnode->vRecvGetData.empty() || (!pnode->vRecvMsg.empty() && pnode->vRecvMsg[0].complete()))
1847                         {
1848                             fSleep = false;
1849                         }
1850                     }
1851                 }
1852             }
1853             boost::this_thread::interruption_point();
1854
1855             // Send messages
1856             {
1857                 TRY_LOCK(pnode->cs_vSend, lockSend);
1858                 if (lockSend)
1859                     GetNodeSignals().SendMessages(pnode, *this);
1860             }
1861             boost::this_thread::interruption_point();
1862         }
1863
1864         {
1865             LOCK(cs_vNodes);
1866             BOOST_FOREACH(CNode* pnode, vNodesCopy)
1867                 pnode->Release();
1868         }
1869
1870         if (fSleep)
1871             messageHandlerCondition.timed_wait(lock, boost::posix_time::microsec_clock::universal_time() + boost::posix_time::milliseconds(100));
1872     }
1873 }
1874
1875
1876
1877
1878
1879
1880 bool CConnman::BindListenPort(const CService &addrBind, std::string& strError, bool fWhitelisted)
1881 {
1882     strError = "";
1883     int nOne = 1;
1884
1885     // Create socket for listening for incoming connections
1886     struct sockaddr_storage sockaddr;
1887     socklen_t len = sizeof(sockaddr);
1888     if (!addrBind.GetSockAddr((struct sockaddr*)&sockaddr, &len))
1889     {
1890         strError = strprintf("Error: Bind address family for %s not supported", addrBind.ToString());
1891         LogPrintf("%s\n", strError);
1892         return false;
1893     }
1894
1895     SOCKET hListenSocket = socket(((struct sockaddr*)&sockaddr)->sa_family, SOCK_STREAM, IPPROTO_TCP);
1896     if (hListenSocket == INVALID_SOCKET)
1897     {
1898         strError = strprintf("Error: Couldn't open socket for incoming connections (socket returned error %s)", NetworkErrorString(WSAGetLastError()));
1899         LogPrintf("%s\n", strError);
1900         return false;
1901     }
1902     if (!IsSelectableSocket(hListenSocket))
1903     {
1904         strError = "Error: Couldn't create a listenable socket for incoming connections";
1905         LogPrintf("%s\n", strError);
1906         return false;
1907     }
1908
1909
1910 #ifndef WIN32
1911 #ifdef SO_NOSIGPIPE
1912     // Different way of disabling SIGPIPE on BSD
1913     setsockopt(hListenSocket, SOL_SOCKET, SO_NOSIGPIPE, (void*)&nOne, sizeof(int));
1914 #endif
1915     // Allow binding if the port is still in TIME_WAIT state after
1916     // the program was closed and restarted.
1917     setsockopt(hListenSocket, SOL_SOCKET, SO_REUSEADDR, (void*)&nOne, sizeof(int));
1918     // Disable Nagle's algorithm
1919     setsockopt(hListenSocket, IPPROTO_TCP, TCP_NODELAY, (void*)&nOne, sizeof(int));
1920 #else
1921     setsockopt(hListenSocket, SOL_SOCKET, SO_REUSEADDR, (const char*)&nOne, sizeof(int));
1922     setsockopt(hListenSocket, IPPROTO_TCP, TCP_NODELAY, (const char*)&nOne, sizeof(int));
1923 #endif
1924
1925     // Set to non-blocking, incoming connections will also inherit this
1926     if (!SetSocketNonBlocking(hListenSocket, true)) {
1927         strError = strprintf("BindListenPort: Setting listening socket to non-blocking failed, error %s\n", NetworkErrorString(WSAGetLastError()));
1928         LogPrintf("%s\n", strError);
1929         return false;
1930     }
1931
1932     // some systems don't have IPV6_V6ONLY but are always v6only; others do have the option
1933     // and enable it by default or not. Try to enable it, if possible.
1934     if (addrBind.IsIPv6()) {
1935 #ifdef IPV6_V6ONLY
1936 #ifdef WIN32
1937         setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_V6ONLY, (const char*)&nOne, sizeof(int));
1938 #else
1939         setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&nOne, sizeof(int));
1940 #endif
1941 #endif
1942 #ifdef WIN32
1943         int nProtLevel = PROTECTION_LEVEL_UNRESTRICTED;
1944         setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_PROTECTION_LEVEL, (const char*)&nProtLevel, sizeof(int));
1945 #endif
1946     }
1947
1948     if (::bind(hListenSocket, (struct sockaddr*)&sockaddr, len) == SOCKET_ERROR)
1949     {
1950         int nErr = WSAGetLastError();
1951         if (nErr == WSAEADDRINUSE)
1952             strError = strprintf(_("Unable to bind to %s on this computer. %s is probably already running."), addrBind.ToString(), _(PACKAGE_NAME));
1953         else
1954             strError = strprintf(_("Unable to bind to %s on this computer (bind returned error %s)"), addrBind.ToString(), NetworkErrorString(nErr));
1955         LogPrintf("%s\n", strError);
1956         CloseSocket(hListenSocket);
1957         return false;
1958     }
1959     LogPrintf("Bound to %s\n", addrBind.ToString());
1960
1961     // Listen for incoming connections
1962     if (listen(hListenSocket, SOMAXCONN) == SOCKET_ERROR)
1963     {
1964         strError = strprintf(_("Error: Listening for incoming connections failed (listen returned error %s)"), NetworkErrorString(WSAGetLastError()));
1965         LogPrintf("%s\n", strError);
1966         CloseSocket(hListenSocket);
1967         return false;
1968     }
1969
1970     vhListenSocket.push_back(ListenSocket(hListenSocket, fWhitelisted));
1971
1972     if (addrBind.IsRoutable() && fDiscover && !fWhitelisted)
1973         AddLocal(addrBind, LOCAL_BIND);
1974
1975     return true;
1976 }
1977
1978 void static Discover(boost::thread_group& threadGroup)
1979 {
1980     if (!fDiscover)
1981         return;
1982
1983 #ifdef WIN32
1984     // Get local host IP
1985     char pszHostName[256] = "";
1986     if (gethostname(pszHostName, sizeof(pszHostName)) != SOCKET_ERROR)
1987     {
1988         std::vector<CNetAddr> vaddr;
1989         if (LookupHost(pszHostName, vaddr, 0, true))
1990         {
1991             BOOST_FOREACH (const CNetAddr &addr, vaddr)
1992             {
1993                 if (AddLocal(addr, LOCAL_IF))
1994                     LogPrintf("%s: %s - %s\n", __func__, pszHostName, addr.ToString());
1995             }
1996         }
1997     }
1998 #else
1999     // Get local host ip
2000     struct ifaddrs* myaddrs;
2001     if (getifaddrs(&myaddrs) == 0)
2002     {
2003         for (struct ifaddrs* ifa = myaddrs; ifa != NULL; ifa = ifa->ifa_next)
2004         {
2005             if (ifa->ifa_addr == NULL) continue;
2006             if ((ifa->ifa_flags & IFF_UP) == 0) continue;
2007             if (strcmp(ifa->ifa_name, "lo") == 0) continue;
2008             if (strcmp(ifa->ifa_name, "lo0") == 0) continue;
2009             if (ifa->ifa_addr->sa_family == AF_INET)
2010             {
2011                 struct sockaddr_in* s4 = (struct sockaddr_in*)(ifa->ifa_addr);
2012                 CNetAddr addr(s4->sin_addr);
2013                 if (AddLocal(addr, LOCAL_IF))
2014                     LogPrintf("%s: IPv4 %s: %s\n", __func__, ifa->ifa_name, addr.ToString());
2015             }
2016             else if (ifa->ifa_addr->sa_family == AF_INET6)
2017             {
2018                 struct sockaddr_in6* s6 = (struct sockaddr_in6*)(ifa->ifa_addr);
2019                 CNetAddr addr(s6->sin6_addr);
2020                 if (AddLocal(addr, LOCAL_IF))
2021                     LogPrintf("%s: IPv6 %s: %s\n", __func__, ifa->ifa_name, addr.ToString());
2022             }
2023         }
2024         freeifaddrs(myaddrs);
2025     }
2026 #endif
2027 }
2028
2029 CConnman::CConnman()
2030 {
2031     setBannedIsDirty = false;
2032     fAddressesInitialized = false;
2033     nLastNodeId = 0;
2034     nSendBufferMaxSize = 0;
2035     nReceiveFloodSize = 0;
2036     semOutbound = NULL;
2037     nMaxConnections = 0;
2038     nMaxOutbound = 0;
2039     nBestHeight = 0;
2040 }
2041
2042 bool StartNode(CConnman& connman, boost::thread_group& threadGroup, CScheduler& scheduler, ServiceFlags nLocalServices, ServiceFlags nRelevantServices, int nMaxConnectionsIn, int nMaxOutboundIn, int nBestHeightIn, std::string& strNodeError)
2043 {
2044     Discover(threadGroup);
2045
2046     bool ret = connman.Start(threadGroup, scheduler, nLocalServices, nRelevantServices, nMaxConnectionsIn, nMaxOutboundIn, nBestHeightIn, strNodeError);
2047
2048     return ret;
2049 }
2050
2051 NodeId CConnman::GetNewNodeId()
2052 {
2053     return nLastNodeId.fetch_add(1, std::memory_order_relaxed);
2054 }
2055
2056 bool CConnman::Start(boost::thread_group& threadGroup, CScheduler& scheduler, ServiceFlags nLocalServicesIn, ServiceFlags nRelevantServicesIn, int nMaxConnectionsIn, int nMaxOutboundIn, int nBestHeightIn, std::string& strNodeError)
2057 {
2058     nTotalBytesRecv = 0;
2059     nTotalBytesSent = 0;
2060     nMaxOutboundLimit = 0;
2061     nMaxOutboundTotalBytesSentInCycle = 0;
2062     nMaxOutboundTimeframe = 60*60*24; //1 day
2063     nLocalServices = nLocalServicesIn;
2064     nRelevantServices = nRelevantServicesIn;
2065     nMaxOutboundCycleStartTime = 0;
2066
2067     nMaxConnections = nMaxConnectionsIn;
2068     nMaxOutbound = std::min((nMaxOutboundIn), nMaxConnections);
2069
2070     nSendBufferMaxSize = 1000*GetArg("-maxsendbuffer", DEFAULT_MAXSENDBUFFER);
2071     nReceiveFloodSize = 1000*GetArg("-maxreceivebuffer", DEFAULT_MAXRECEIVEBUFFER);
2072
2073     SetBestHeight(nBestHeightIn);
2074
2075     uiInterface.InitMessage(_("Loading addresses..."));
2076     // Load addresses from peers.dat
2077     int64_t nStart = GetTimeMillis();
2078     {
2079         CAddrDB adb;
2080         if (adb.Read(addrman))
2081             LogPrintf("Loaded %i addresses from peers.dat  %dms\n", addrman.size(), GetTimeMillis() - nStart);
2082         else {
2083             addrman.Clear(); // Addrman can be in an inconsistent state after failure, reset it
2084             LogPrintf("Invalid or missing peers.dat; recreating\n");
2085             DumpAddresses();
2086         }
2087     }
2088
2089     uiInterface.InitMessage(_("Loading banlist..."));
2090     // Load addresses from banlist.dat
2091     nStart = GetTimeMillis();
2092     CBanDB bandb;
2093     banmap_t banmap;
2094     if (bandb.Read(banmap)) {
2095         SetBanned(banmap); // thread save setter
2096         SetBannedSetDirty(false); // no need to write down, just read data
2097         SweepBanned(); // sweep out unused entries
2098
2099         LogPrint("net", "Loaded %d banned node ips/subnets from banlist.dat  %dms\n",
2100             banmap.size(), GetTimeMillis() - nStart);
2101     } else {
2102         LogPrintf("Invalid or missing banlist.dat; recreating\n");
2103         SetBannedSetDirty(true); // force write
2104         DumpBanlist();
2105     }
2106
2107     uiInterface.InitMessage(_("Starting network threads..."));
2108
2109     fAddressesInitialized = true;
2110
2111     if (semOutbound == NULL) {
2112         // initialize semaphore
2113         semOutbound = new CSemaphore(std::min((nMaxOutbound + MAX_FEELER_CONNECTIONS), nMaxConnections));
2114     }
2115
2116     if (pnodeLocalHost == NULL) {
2117         CNetAddr local;
2118         LookupHost("127.0.0.1", local, false);
2119         pnodeLocalHost = new CNode(GetNewNodeId(), nLocalServices, GetBestHeight(), INVALID_SOCKET, CAddress(CService(local, 0), nLocalServices));
2120         GetNodeSignals().InitializeNode(pnodeLocalHost->GetId(), pnodeLocalHost);
2121     }
2122
2123     //
2124     // Start threads
2125     //
2126
2127     if (!GetBoolArg("-dnsseed", true))
2128         LogPrintf("DNS seeding disabled\n");
2129     else
2130         threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "dnsseed", boost::function<void()>(boost::bind(&CConnman::ThreadDNSAddressSeed, this))));
2131
2132     // Map ports with UPnP
2133     MapPort(GetBoolArg("-upnp", DEFAULT_UPNP));
2134
2135     // Send and receive from sockets, accept connections
2136     threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "net", boost::function<void()>(boost::bind(&CConnman::ThreadSocketHandler, this))));
2137
2138     // Initiate outbound connections from -addnode
2139     threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "addcon", boost::function<void()>(boost::bind(&CConnman::ThreadOpenAddedConnections, this))));
2140
2141     // Initiate outbound connections
2142     threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "opencon", boost::function<void()>(boost::bind(&CConnman::ThreadOpenConnections, this))));
2143
2144     // Process messages
2145     threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "msghand", boost::function<void()>(boost::bind(&CConnman::ThreadMessageHandler, this))));
2146
2147     // Dump network addresses
2148     scheduler.scheduleEvery(boost::bind(&CConnman::DumpData, this), DUMP_ADDRESSES_INTERVAL);
2149
2150     return true;
2151 }
2152
2153 bool StopNode(CConnman& connman)
2154 {
2155     LogPrintf("StopNode()\n");
2156     MapPort(false);
2157
2158     connman.Stop();
2159     return true;
2160 }
2161
2162 class CNetCleanup
2163 {
2164 public:
2165     CNetCleanup() {}
2166
2167     ~CNetCleanup()
2168     {
2169 #ifdef WIN32
2170         // Shutdown Windows Sockets
2171         WSACleanup();
2172 #endif
2173     }
2174 }
2175 instance_of_cnetcleanup;
2176
2177 void CConnman::Stop()
2178 {
2179     if (semOutbound)
2180         for (int i=0; i<(nMaxOutbound + MAX_FEELER_CONNECTIONS); i++)
2181             semOutbound->post();
2182
2183     if (fAddressesInitialized)
2184     {
2185         DumpData();
2186         fAddressesInitialized = false;
2187     }
2188
2189     // Close sockets
2190     BOOST_FOREACH(CNode* pnode, vNodes)
2191         if (pnode->hSocket != INVALID_SOCKET)
2192             CloseSocket(pnode->hSocket);
2193     BOOST_FOREACH(ListenSocket& hListenSocket, vhListenSocket)
2194         if (hListenSocket.socket != INVALID_SOCKET)
2195             if (!CloseSocket(hListenSocket.socket))
2196                 LogPrintf("CloseSocket(hListenSocket) failed with error %s\n", NetworkErrorString(WSAGetLastError()));
2197
2198     // clean up some globals (to help leak detection)
2199     BOOST_FOREACH(CNode *pnode, vNodes) {
2200         DeleteNode(pnode);
2201     }
2202     BOOST_FOREACH(CNode *pnode, vNodesDisconnected) {
2203         DeleteNode(pnode);
2204     }
2205     vNodes.clear();
2206     vNodesDisconnected.clear();
2207     vhListenSocket.clear();
2208     delete semOutbound;
2209     semOutbound = NULL;
2210     if(pnodeLocalHost)
2211         DeleteNode(pnodeLocalHost);
2212     pnodeLocalHost = NULL;
2213 }
2214
2215 void CConnman::DeleteNode(CNode* pnode)
2216 {
2217     assert(pnode);
2218     bool fUpdateConnectionTime = false;
2219     GetNodeSignals().FinalizeNode(pnode->GetId(), fUpdateConnectionTime);
2220     if(fUpdateConnectionTime)
2221         addrman.Connected(pnode->addr);
2222     delete pnode;
2223 }
2224
2225 CConnman::~CConnman()
2226 {
2227 }
2228
2229 size_t CConnman::GetAddressCount() const
2230 {
2231     return addrman.size();
2232 }
2233
2234 void CConnman::SetServices(const CService &addr, ServiceFlags nServices)
2235 {
2236     addrman.SetServices(addr, nServices);
2237 }
2238
2239 void CConnman::MarkAddressGood(const CAddress& addr)
2240 {
2241     addrman.Good(addr);
2242 }
2243
2244 void CConnman::AddNewAddress(const CAddress& addr, const CAddress& addrFrom, int64_t nTimePenalty)
2245 {
2246     addrman.Add(addr, addrFrom, nTimePenalty);
2247 }
2248
2249 void CConnman::AddNewAddresses(const std::vector<CAddress>& vAddr, const CAddress& addrFrom, int64_t nTimePenalty)
2250 {
2251     addrman.Add(vAddr, addrFrom, nTimePenalty);
2252 }
2253
2254 std::vector<CAddress> CConnman::GetAddresses()
2255 {
2256     return addrman.GetAddr();
2257 }
2258
2259 bool CConnman::AddNode(const std::string& strNode)
2260 {
2261     LOCK(cs_vAddedNodes);
2262     for(std::vector<std::string>::const_iterator it = vAddedNodes.begin(); it != vAddedNodes.end(); ++it) {
2263         if (strNode == *it)
2264             return false;
2265     }
2266
2267     vAddedNodes.push_back(strNode);
2268     return true;
2269 }
2270
2271 bool CConnman::RemoveAddedNode(const std::string& strNode)
2272 {
2273     LOCK(cs_vAddedNodes);
2274     for(std::vector<std::string>::iterator it = vAddedNodes.begin(); it != vAddedNodes.end(); ++it) {
2275         if (strNode == *it) {
2276             vAddedNodes.erase(it);
2277             return true;
2278         }
2279     }
2280     return false;
2281 }
2282
2283 size_t CConnman::GetNodeCount(NumConnections flags)
2284 {
2285     LOCK(cs_vNodes);
2286     if (flags == CConnman::CONNECTIONS_ALL) // Shortcut if we want total
2287         return vNodes.size();
2288
2289     int nNum = 0;
2290     for(std::vector<CNode*>::const_iterator it = vNodes.begin(); it != vNodes.end(); ++it)
2291         if (flags & ((*it)->fInbound ? CONNECTIONS_IN : CONNECTIONS_OUT))
2292             nNum++;
2293
2294     return nNum;
2295 }
2296
2297 void CConnman::GetNodeStats(std::vector<CNodeStats>& vstats)
2298 {
2299     vstats.clear();
2300     LOCK(cs_vNodes);
2301     vstats.reserve(vNodes.size());
2302     for(std::vector<CNode*>::iterator it = vNodes.begin(); it != vNodes.end(); ++it) {
2303         CNode* pnode = *it;
2304         CNodeStats stats;
2305         pnode->copyStats(stats);
2306         vstats.push_back(stats);
2307     }
2308 }
2309
2310 bool CConnman::DisconnectAddress(const CNetAddr& netAddr)
2311 {
2312     if (CNode* pnode = FindNode(netAddr)) {
2313         pnode->fDisconnect = true;
2314         return true;
2315     }
2316     return false;
2317 }
2318
2319 bool CConnman::DisconnectSubnet(const CSubNet& subNet)
2320 {
2321     if (CNode* pnode = FindNode(subNet)) {
2322         pnode->fDisconnect = true;
2323         return true;
2324     }
2325     return false;
2326 }
2327
2328 bool CConnman::DisconnectNode(const std::string& strNode)
2329 {
2330     if (CNode* pnode = FindNode(strNode)) {
2331         pnode->fDisconnect = true;
2332         return true;
2333     }
2334     return false;
2335 }
2336 bool CConnman::DisconnectNode(NodeId id)
2337 {
2338     LOCK(cs_vNodes);
2339     for(CNode* pnode : vNodes) {
2340         if (id == pnode->id) {
2341             pnode->fDisconnect = true;
2342             return true;
2343         }
2344     }
2345     return false;
2346 }
2347
2348 void CConnman::RelayTransaction(const CTransaction& tx)
2349 {
2350     CInv inv(MSG_TX, tx.GetHash());
2351     LOCK(cs_vNodes);
2352     BOOST_FOREACH(CNode* pnode, vNodes)
2353     {
2354         pnode->PushInventory(inv);
2355     }
2356 }
2357
2358 void CConnman::RecordBytesRecv(uint64_t bytes)
2359 {
2360     LOCK(cs_totalBytesRecv);
2361     nTotalBytesRecv += bytes;
2362 }
2363
2364 void CConnman::RecordBytesSent(uint64_t bytes)
2365 {
2366     LOCK(cs_totalBytesSent);
2367     nTotalBytesSent += bytes;
2368
2369     uint64_t now = GetTime();
2370     if (nMaxOutboundCycleStartTime + nMaxOutboundTimeframe < now)
2371     {
2372         // timeframe expired, reset cycle
2373         nMaxOutboundCycleStartTime = now;
2374         nMaxOutboundTotalBytesSentInCycle = 0;
2375     }
2376
2377     // TODO, exclude whitebind peers
2378     nMaxOutboundTotalBytesSentInCycle += bytes;
2379 }
2380
2381 void CConnman::SetMaxOutboundTarget(uint64_t limit)
2382 {
2383     LOCK(cs_totalBytesSent);
2384     uint64_t recommendedMinimum = (nMaxOutboundTimeframe / 600) * MAX_BLOCK_SERIALIZED_SIZE;
2385     nMaxOutboundLimit = limit;
2386
2387     if (limit > 0 && limit < recommendedMinimum)
2388         LogPrintf("Max outbound target is very small (%s bytes) and will be overshot. Recommended minimum is %s bytes.\n", nMaxOutboundLimit, recommendedMinimum);
2389 }
2390
2391 uint64_t CConnman::GetMaxOutboundTarget()
2392 {
2393     LOCK(cs_totalBytesSent);
2394     return nMaxOutboundLimit;
2395 }
2396
2397 uint64_t CConnman::GetMaxOutboundTimeframe()
2398 {
2399     LOCK(cs_totalBytesSent);
2400     return nMaxOutboundTimeframe;
2401 }
2402
2403 uint64_t CConnman::GetMaxOutboundTimeLeftInCycle()
2404 {
2405     LOCK(cs_totalBytesSent);
2406     if (nMaxOutboundLimit == 0)
2407         return 0;
2408
2409     if (nMaxOutboundCycleStartTime == 0)
2410         return nMaxOutboundTimeframe;
2411
2412     uint64_t cycleEndTime = nMaxOutboundCycleStartTime + nMaxOutboundTimeframe;
2413     uint64_t now = GetTime();
2414     return (cycleEndTime < now) ? 0 : cycleEndTime - GetTime();
2415 }
2416
2417 void CConnman::SetMaxOutboundTimeframe(uint64_t timeframe)
2418 {
2419     LOCK(cs_totalBytesSent);
2420     if (nMaxOutboundTimeframe != timeframe)
2421     {
2422         // reset measure-cycle in case of changing
2423         // the timeframe
2424         nMaxOutboundCycleStartTime = GetTime();
2425     }
2426     nMaxOutboundTimeframe = timeframe;
2427 }
2428
2429 bool CConnman::OutboundTargetReached(bool historicalBlockServingLimit)
2430 {
2431     LOCK(cs_totalBytesSent);
2432     if (nMaxOutboundLimit == 0)
2433         return false;
2434
2435     if (historicalBlockServingLimit)
2436     {
2437         // keep a large enough buffer to at least relay each block once
2438         uint64_t timeLeftInCycle = GetMaxOutboundTimeLeftInCycle();
2439         uint64_t buffer = timeLeftInCycle / 600 * MAX_BLOCK_SERIALIZED_SIZE;
2440         if (buffer >= nMaxOutboundLimit || nMaxOutboundTotalBytesSentInCycle >= nMaxOutboundLimit - buffer)
2441             return true;
2442     }
2443     else if (nMaxOutboundTotalBytesSentInCycle >= nMaxOutboundLimit)
2444         return true;
2445
2446     return false;
2447 }
2448
2449 uint64_t CConnman::GetOutboundTargetBytesLeft()
2450 {
2451     LOCK(cs_totalBytesSent);
2452     if (nMaxOutboundLimit == 0)
2453         return 0;
2454
2455     return (nMaxOutboundTotalBytesSentInCycle >= nMaxOutboundLimit) ? 0 : nMaxOutboundLimit - nMaxOutboundTotalBytesSentInCycle;
2456 }
2457
2458 uint64_t CConnman::GetTotalBytesRecv()
2459 {
2460     LOCK(cs_totalBytesRecv);
2461     return nTotalBytesRecv;
2462 }
2463
2464 uint64_t CConnman::GetTotalBytesSent()
2465 {
2466     LOCK(cs_totalBytesSent);
2467     return nTotalBytesSent;
2468 }
2469
2470 ServiceFlags CConnman::GetLocalServices() const
2471 {
2472     return nLocalServices;
2473 }
2474
2475 void CConnman::SetBestHeight(int height)
2476 {
2477     nBestHeight.store(height, std::memory_order_release);
2478 }
2479
2480 int CConnman::GetBestHeight() const
2481 {
2482     return nBestHeight.load(std::memory_order_acquire);
2483 }
2484
2485 void CNode::Fuzz(int nChance)
2486 {
2487     if (!fSuccessfullyConnected) return; // Don't fuzz initial handshake
2488     if (GetRand(nChance) != 0) return; // Fuzz 1 of every nChance messages
2489
2490     switch (GetRand(3))
2491     {
2492     case 0:
2493         // xor a random byte with a random value:
2494         if (!ssSend.empty()) {
2495             CDataStream::size_type pos = GetRand(ssSend.size());
2496             ssSend[pos] ^= (unsigned char)(GetRand(256));
2497         }
2498         break;
2499     case 1:
2500         // delete a random byte:
2501         if (!ssSend.empty()) {
2502             CDataStream::size_type pos = GetRand(ssSend.size());
2503             ssSend.erase(ssSend.begin()+pos);
2504         }
2505         break;
2506     case 2:
2507         // insert a random byte at a random position
2508         {
2509             CDataStream::size_type pos = GetRand(ssSend.size());
2510             char ch = (char)GetRand(256);
2511             ssSend.insert(ssSend.begin()+pos, ch);
2512         }
2513         break;
2514     }
2515     // Chance of more than one change half the time:
2516     // (more changes exponentially less likely):
2517     Fuzz(2);
2518 }
2519
2520 unsigned int CConnman::GetReceiveFloodSize() const { return nReceiveFloodSize; }
2521 unsigned int CConnman::GetSendBufferSize() const{ return nSendBufferMaxSize; }
2522
2523 CNode::CNode(NodeId idIn, ServiceFlags nLocalServicesIn, int nMyStartingHeightIn, SOCKET hSocketIn, const CAddress& addrIn, const std::string& addrNameIn, bool fInboundIn) :
2524     ssSend(SER_NETWORK, INIT_PROTO_VERSION),
2525     addr(addrIn),
2526     nKeyedNetGroup(CalculateKeyedNetGroup(addrIn)),
2527     addrKnown(5000, 0.001),
2528     filterInventoryKnown(50000, 0.000001)
2529 {
2530     nServices = NODE_NONE;
2531     nServicesExpected = NODE_NONE;
2532     hSocket = hSocketIn;
2533     nRecvVersion = INIT_PROTO_VERSION;
2534     nLastSend = 0;
2535     nLastRecv = 0;
2536     nSendBytes = 0;
2537     nRecvBytes = 0;
2538     nTimeConnected = GetTime();
2539     nTimeOffset = 0;
2540     addrName = addrNameIn == "" ? addr.ToStringIPPort() : addrNameIn;
2541     nVersion = 0;
2542     strSubVer = "";
2543     fWhitelisted = false;
2544     fOneShot = false;
2545     fClient = false; // set by version message
2546     fFeeler = false;
2547     fInbound = fInboundIn;
2548     fNetworkNode = false;
2549     fSuccessfullyConnected = false;
2550     fDisconnect = false;
2551     nRefCount = 0;
2552     nSendSize = 0;
2553     nSendOffset = 0;
2554     hashContinue = uint256();
2555     nStartingHeight = -1;
2556     filterInventoryKnown.reset();
2557     fSendMempool = false;
2558     fGetAddr = false;
2559     nNextLocalAddrSend = 0;
2560     nNextAddrSend = 0;
2561     nNextInvSend = 0;
2562     fRelayTxes = false;
2563     fSentAddr = false;
2564     pfilter = new CBloomFilter();
2565     timeLastMempoolReq = 0;
2566     nLastBlockTime = 0;
2567     nLastTXTime = 0;
2568     nPingNonceSent = 0;
2569     nPingUsecStart = 0;
2570     nPingUsecTime = 0;
2571     fPingQueued = false;
2572     nMinPingUsecTime = std::numeric_limits<int64_t>::max();
2573     minFeeFilter = 0;
2574     lastSentFeeFilter = 0;
2575     nextSendTimeFeeFilter = 0;
2576     id = idIn;
2577     nOptimisticBytesWritten = 0;
2578     nLocalServices = nLocalServicesIn;
2579
2580     GetRandBytes((unsigned char*)&nLocalHostNonce, sizeof(nLocalHostNonce));
2581     nMyStartingHeight = nMyStartingHeightIn;
2582
2583     BOOST_FOREACH(const std::string &msg, getAllNetMessageTypes())
2584         mapRecvBytesPerMsgCmd[msg] = 0;
2585     mapRecvBytesPerMsgCmd[NET_MESSAGE_COMMAND_OTHER] = 0;
2586
2587     if (fLogIPs)
2588         LogPrint("net", "Added connection to %s peer=%d\n", addrName, id);
2589     else
2590         LogPrint("net", "Added connection peer=%d\n", id);
2591
2592     // Be shy and don't send version until we hear
2593     if (hSocket != INVALID_SOCKET && !fInbound)
2594         PushVersion();
2595 }
2596
2597 CNode::~CNode()
2598 {
2599     CloseSocket(hSocket);
2600
2601     if (pfilter)
2602         delete pfilter;
2603 }
2604
2605 void CNode::AskFor(const CInv& inv)
2606 {
2607     if (mapAskFor.size() > MAPASKFOR_MAX_SZ || setAskFor.size() > SETASKFOR_MAX_SZ)
2608         return;
2609     // a peer may not have multiple non-responded queue positions for a single inv item
2610     if (!setAskFor.insert(inv.hash).second)
2611         return;
2612
2613     // We're using mapAskFor as a priority queue,
2614     // the key is the earliest time the request can be sent
2615     int64_t nRequestTime;
2616     limitedmap<uint256, int64_t>::const_iterator it = mapAlreadyAskedFor.find(inv.hash);
2617     if (it != mapAlreadyAskedFor.end())
2618         nRequestTime = it->second;
2619     else
2620         nRequestTime = 0;
2621     LogPrint("net", "askfor %s  %d (%s) peer=%d\n", inv.ToString(), nRequestTime, DateTimeStrFormat("%H:%M:%S", nRequestTime/1000000), id);
2622
2623     // Make sure not to reuse time indexes to keep things in the same order
2624     int64_t nNow = GetTimeMicros() - 1000000;
2625     static int64_t nLastTime;
2626     ++nLastTime;
2627     nNow = std::max(nNow, nLastTime);
2628     nLastTime = nNow;
2629
2630     // Each retry is 2 minutes after the last
2631     nRequestTime = std::max(nRequestTime + 2 * 60 * 1000000, nNow);
2632     if (it != mapAlreadyAskedFor.end())
2633         mapAlreadyAskedFor.update(it, nRequestTime);
2634     else
2635         mapAlreadyAskedFor.insert(std::make_pair(inv.hash, nRequestTime));
2636     mapAskFor.insert(std::make_pair(nRequestTime, inv));
2637 }
2638
2639 void CNode::BeginMessage(const char* pszCommand) EXCLUSIVE_LOCK_FUNCTION(cs_vSend)
2640 {
2641     ENTER_CRITICAL_SECTION(cs_vSend);
2642     assert(ssSend.size() == 0);
2643     ssSend << CMessageHeader(Params().MessageStart(), pszCommand, 0);
2644     LogPrint("net", "sending: %s ", SanitizeString(pszCommand));
2645 }
2646
2647 void CNode::AbortMessage() UNLOCK_FUNCTION(cs_vSend)
2648 {
2649     ssSend.clear();
2650
2651     LEAVE_CRITICAL_SECTION(cs_vSend);
2652
2653     LogPrint("net", "(aborted)\n");
2654 }
2655
2656 void CNode::EndMessage(const char* pszCommand) UNLOCK_FUNCTION(cs_vSend)
2657 {
2658     // The -*messagestest options are intentionally not documented in the help message,
2659     // since they are only used during development to debug the networking code and are
2660     // not intended for end-users.
2661     if (mapArgs.count("-dropmessagestest") && GetRand(GetArg("-dropmessagestest", 2)) == 0)
2662     {
2663         LogPrint("net", "dropmessages DROPPING SEND MESSAGE\n");
2664         AbortMessage();
2665         return;
2666     }
2667     if (mapArgs.count("-fuzzmessagestest"))
2668         Fuzz(GetArg("-fuzzmessagestest", 10));
2669
2670     if (ssSend.size() == 0)
2671     {
2672         LEAVE_CRITICAL_SECTION(cs_vSend);
2673         return;
2674     }
2675     // Set the size
2676     unsigned int nSize = ssSend.size() - CMessageHeader::HEADER_SIZE;
2677     WriteLE32((uint8_t*)&ssSend[CMessageHeader::MESSAGE_SIZE_OFFSET], nSize);
2678
2679     //log total amount of bytes per command
2680     mapSendBytesPerMsgCmd[std::string(pszCommand)] += nSize + CMessageHeader::HEADER_SIZE;
2681
2682     // Set the checksum
2683     uint256 hash = Hash(ssSend.begin() + CMessageHeader::HEADER_SIZE, ssSend.end());
2684     unsigned int nChecksum = 0;
2685     memcpy(&nChecksum, &hash, sizeof(nChecksum));
2686     assert(ssSend.size () >= CMessageHeader::CHECKSUM_OFFSET + sizeof(nChecksum));
2687     memcpy((char*)&ssSend[CMessageHeader::CHECKSUM_OFFSET], &nChecksum, sizeof(nChecksum));
2688
2689     LogPrint("net", "(%d bytes) peer=%d\n", nSize, id);
2690
2691     std::deque<CSerializeData>::iterator it = vSendMsg.insert(vSendMsg.end(), CSerializeData());
2692     ssSend.GetAndClear(*it);
2693     nSendSize += (*it).size();
2694
2695     // If write queue empty, attempt "optimistic write"
2696     if (it == vSendMsg.begin())
2697         nOptimisticBytesWritten += SocketSendData(this);
2698
2699     LEAVE_CRITICAL_SECTION(cs_vSend);
2700 }
2701
2702 bool CConnman::ForNode(NodeId id, std::function<bool(CNode* pnode)> func)
2703 {
2704     CNode* found = nullptr;
2705     LOCK(cs_vNodes);
2706     for (auto&& pnode : vNodes) {
2707         if(pnode->id == id) {
2708             found = pnode;
2709             break;
2710         }
2711     }
2712     return found != nullptr && func(found);
2713 }
2714
2715 bool CConnman::ForEachNode(std::function<bool(CNode* pnode)> func)
2716 {
2717     LOCK(cs_vNodes);
2718     for (auto&& node : vNodes)
2719         if(!func(node))
2720             return false;
2721     return true;
2722 }
2723
2724 bool CConnman::ForEachNode(std::function<bool(const CNode* pnode)> func) const
2725 {
2726     LOCK(cs_vNodes);
2727     for (const auto& node : vNodes)
2728         if(!func(node))
2729             return false;
2730     return true;
2731 }
2732
2733 bool CConnman::ForEachNodeThen(std::function<bool(CNode* pnode)> pre, std::function<void()> post)
2734 {
2735     bool ret = true;
2736     LOCK(cs_vNodes);
2737     for (auto&& node : vNodes)
2738         if(!pre(node)) {
2739             ret = false;
2740             break;
2741         }
2742     post();
2743     return ret;
2744 }
2745
2746 bool CConnman::ForEachNodeThen(std::function<bool(const CNode* pnode)> pre, std::function<void()> post) const
2747 {
2748     bool ret = true;
2749     LOCK(cs_vNodes);
2750     for (const auto& node : vNodes)
2751         if(!pre(node)) {
2752             ret = false;
2753             break;
2754         }
2755     post();
2756     return ret;
2757 }
2758
2759 int64_t PoissonNextSend(int64_t nNow, int average_interval_seconds) {
2760     return nNow + (int64_t)(log1p(GetRand(1ULL << 48) * -0.0000000000000035527136788 /* -1/2^48 */) * average_interval_seconds * -1000000.0 + 0.5);
2761 }
2762
2763 /* static */ uint64_t CNode::CalculateKeyedNetGroup(const CAddress& ad)
2764 {
2765     static const uint64_t k0 = GetRand(std::numeric_limits<uint64_t>::max());
2766     static const uint64_t k1 = GetRand(std::numeric_limits<uint64_t>::max());
2767
2768     std::vector<unsigned char> vchNetGroup(ad.GetGroup());
2769
2770     return CSipHasher(k0, k1).Write(&vchNetGroup[0], vchNetGroup.size()).Finalize();
2771 }