src/netbase.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2016 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 #include <netbase.h>
   7
   8 #include <hash.h>
   9 #include <sync.h>
  10 #include <uint256.h>
  11 #include <random.h>
  12 #include <util.h>
  13 #include <utilstrencodings.h>
  14
  15 #include <atomic>
  16
  17 #ifndef WIN32
  18 #include <fcntl.h>
  19 #endif
  20
  21 #include <boost/algorithm/string/case_conv.hpp> // for to_lower()
  22 #include <boost/algorithm/string/predicate.hpp> // for startswith() and endswith()
  23
  24 #if !defined(HAVE_MSG_NOSIGNAL)
  25 #define MSG_NOSIGNAL 0
  26 #endif
  27
  28 // Settings
  29 static proxyType proxyInfo[NET_MAX];
  30 static proxyType nameProxy;
  31 static CCriticalSection cs_proxyInfos;
  32 int nConnectTimeout = DEFAULT_CONNECT_TIMEOUT;
  33 bool fNameLookup = DEFAULT_NAME_LOOKUP;
  34
  35 // Need ample time for negotiation for very slow proxies such as Tor (milliseconds)
  36 static const int SOCKS5_RECV_TIMEOUT = 20 * 1000;
  37 static std::atomic<bool> interruptSocks5Recv(false);
  38
  39 enum Network ParseNetwork(std::string net) {
  40     boost::to_lower(net);
  41     if (net == "ipv4") return NET_IPV4;
  42     if (net == "ipv6") return NET_IPV6;
  43     if (net == "tor" || net == "onion")  return NET_TOR;
  44     return NET_UNROUTABLE;
  45 }
  46
  47 std::string GetNetworkName(enum Network net) {
  48     switch(net)
  49     {
  50     case NET_IPV4: return "ipv4";
  51     case NET_IPV6: return "ipv6";
  52     case NET_TOR: return "onion";
  53     default: return "";
  54     }
  55 }
  56
  57 bool static LookupIntern(const char *pszName, std::vector<CNetAddr>& vIP, unsigned int nMaxSolutions, bool fAllowLookup)
  58 {
  59     vIP.clear();
  60
  61     {
  62         CNetAddr addr;
  63         if (addr.SetSpecial(std::string(pszName))) {
  64             vIP.push_back(addr);
  65             return true;
  66         }
  67     }
  68
  69     struct addrinfo aiHint;
  70     memset(&aiHint, 0, sizeof(struct addrinfo));
  71
  72     aiHint.ai_socktype = SOCK_STREAM;
  73     aiHint.ai_protocol = IPPROTO_TCP;
  74     aiHint.ai_family = AF_UNSPEC;
  75 #ifdef WIN32
  76     aiHint.ai_flags = fAllowLookup ? 0 : AI_NUMERICHOST;
  77 #else
  78     aiHint.ai_flags = fAllowLookup ? AI_ADDRCONFIG : AI_NUMERICHOST;
  79 #endif
  80     struct addrinfo *aiRes = nullptr;
  81     int nErr = getaddrinfo(pszName, nullptr, &aiHint, &aiRes);
  82     if (nErr)
  83         return false;
  84
  85     struct addrinfo *aiTrav = aiRes;
  86     while (aiTrav != nullptr && (nMaxSolutions == 0 || vIP.size() < nMaxSolutions))
  87     {
  88         CNetAddr resolved;
  89         if (aiTrav->ai_family == AF_INET)
  90         {
  91             assert(aiTrav->ai_addrlen >= sizeof(sockaddr_in));
  92             resolved = CNetAddr(((struct sockaddr_in*)(aiTrav->ai_addr))->sin_addr);
  93         }
  94
  95         if (aiTrav->ai_family == AF_INET6)
  96         {
  97             assert(aiTrav->ai_addrlen >= sizeof(sockaddr_in6));
  98             struct sockaddr_in6* s6 = (struct sockaddr_in6*) aiTrav->ai_addr;
  99             resolved = CNetAddr(s6->sin6_addr, s6->sin6_scope_id);
 100         }
 101         /* Never allow resolving to an internal address. Consider any such result invalid */
 102         if (!resolved.IsInternal()) {
 103             vIP.push_back(resolved);
 104         }
 105
 106         aiTrav = aiTrav->ai_next;
 107     }
 108
 109     freeaddrinfo(aiRes);
 110
 111     return (vIP.size() > 0);
 112 }
 113
 114 bool LookupHost(const char *pszName, std::vector<CNetAddr>& vIP, unsigned int nMaxSolutions, bool fAllowLookup)
 115 {
 116     std::string strHost(pszName);
 117     if (strHost.empty())
 118         return false;
 119     if (boost::algorithm::starts_with(strHost, "[") && boost::algorithm::ends_with(strHost, "]"))
 120     {
 121         strHost = strHost.substr(1, strHost.size() - 2);
 122     }
 123
 124     return LookupIntern(strHost.c_str(), vIP, nMaxSolutions, fAllowLookup);
 125 }
 126
 127 bool LookupHost(const char *pszName, CNetAddr& addr, bool fAllowLookup)
 128 {
 129     std::vector<CNetAddr> vIP;
 130     LookupHost(pszName, vIP, 1, fAllowLookup);
 131     if(vIP.empty())
 132         return false;
 133     addr = vIP.front();
 134     return true;
 135 }
 136
 137 bool Lookup(const char *pszName, std::vector<CService>& vAddr, int portDefault, bool fAllowLookup, unsigned int nMaxSolutions)
 138 {
 139     if (pszName[0] == 0)
 140         return false;
 141     int port = portDefault;
 142     std::string hostname = "";
 143     SplitHostPort(std::string(pszName), port, hostname);
 144
 145     std::vector<CNetAddr> vIP;
 146     bool fRet = LookupIntern(hostname.c_str(), vIP, nMaxSolutions, fAllowLookup);
 147     if (!fRet)
 148         return false;
 149     vAddr.resize(vIP.size());
 150     for (unsigned int i = 0; i < vIP.size(); i++)
 151         vAddr[i] = CService(vIP[i], port);
 152     return true;
 153 }
 154
 155 bool Lookup(const char *pszName, CService& addr, int portDefault, bool fAllowLookup)
 156 {
 157     std::vector<CService> vService;
 158     bool fRet = Lookup(pszName, vService, portDefault, fAllowLookup, 1);
 159     if (!fRet)
 160         return false;
 161     addr = vService[0];
 162     return true;
 163 }
 164
 165 CService LookupNumeric(const char *pszName, int portDefault)
 166 {
 167     CService addr;
 168     // "1.2:345" will fail to resolve the ip, but will still set the port.
 169     // If the ip fails to resolve, re-init the result.
 170     if(!Lookup(pszName, addr, portDefault, false))
 171         addr = CService();
 172     return addr;
 173 }
 174
 175 struct timeval MillisToTimeval(int64_t nTimeout)
 176 {
 177     struct timeval timeout;
 178     timeout.tv_sec  = nTimeout / 1000;
 179     timeout.tv_usec = (nTimeout % 1000) * 1000;
 180     return timeout;
 181 }
 182
 183 /** SOCKS version */
 184 enum SOCKSVersion: uint8_t {
 185     SOCKS4 = 0x04,
 186     SOCKS5 = 0x05
 187 };
 188
 189 /** Values defined for METHOD in RFC1928 */
 190 enum SOCKS5Method: uint8_t {
 191     NOAUTH = 0x00,        //! No authentication required
 192     GSSAPI = 0x01,        //! GSSAPI
 193     USER_PASS = 0x02,     //! Username/password
 194     NO_ACCEPTABLE = 0xff, //! No acceptable methods
 195 };
 196
 197 /** Values defined for CMD in RFC1928 */
 198 enum SOCKS5Command: uint8_t {
 199     CONNECT = 0x01,
 200     BIND = 0x02,
 201     UDP_ASSOCIATE = 0x03
 202 };
 203
 204 /** Values defined for REP in RFC1928 */
 205 enum SOCKS5Reply: uint8_t {
 206     SUCCEEDED = 0x00,        //! Succeeded
 207     GENFAILURE = 0x01,       //! General failure
 208     NOTALLOWED = 0x02,       //! Connection not allowed by ruleset
 209     NETUNREACHABLE = 0x03,   //! Network unreachable
 210     HOSTUNREACHABLE = 0x04,  //! Network unreachable
 211     CONNREFUSED = 0x05,      //! Connection refused
 212     TTLEXPIRED = 0x06,       //! TTL expired
 213     CMDUNSUPPORTED = 0x07,   //! Command not supported
 214     ATYPEUNSUPPORTED = 0x08, //! Address type not supported
 215 };
 216
 217 /** Values defined for ATYPE in RFC1928 */
 218 enum SOCKS5Atyp: uint8_t {
 219     IPV4 = 0x01,
 220     DOMAINNAME = 0x03,
 221     IPV6 = 0x04,
 222 };
 223
 224 /** Status codes that can be returned by InterruptibleRecv */
 225 enum class IntrRecvError {
 226     OK,
 227     Timeout,
 228     Disconnected,
 229     NetworkError,
 230     Interrupted
 231 };
 232
 233 /**
 234  * Read bytes from socket. This will either read the full number of bytes requested
 235  * or return False on error or timeout.
 236  * This function can be interrupted by calling InterruptSocks5()
 237  *
 238  * @param data Buffer to receive into
 239  * @param len  Length of data to receive
 240  * @param timeout  Timeout in milliseconds for receive operation
 241  *
 242  * @note This function requires that hSocket is in non-blocking mode.
 243  */
 244 static IntrRecvError InterruptibleRecv(uint8_t* data, size_t len, int timeout, const SOCKET& hSocket)
 245 {
 246     int64_t curTime = GetTimeMillis();
 247     int64_t endTime = curTime + timeout;
 248     // Maximum time to wait in one select call. It will take up until this time (in millis)
 249     // to break off in case of an interruption.
 250     const int64_t maxWait = 1000;
 251     while (len > 0 && curTime < endTime) {
 252         ssize_t ret = recv(hSocket, (char*)data, len, 0); // Optimistically try the recv first
 253         if (ret > 0) {
 254             len -= ret;
 255             data += ret;
 256         } else if (ret == 0) { // Unexpected disconnection
 257             return IntrRecvError::Disconnected;
 258         } else { // Other error or blocking
 259             int nErr = WSAGetLastError();
 260             if (nErr == WSAEINPROGRESS || nErr == WSAEWOULDBLOCK || nErr == WSAEINVAL) {
 261                 if (!IsSelectableSocket(hSocket)) {
 262                     return IntrRecvError::NetworkError;
 263                 }
 264                 struct timeval tval = MillisToTimeval(std::min(endTime - curTime, maxWait));
 265                 fd_set fdset;
 266                 FD_ZERO(&fdset);
 267                 FD_SET(hSocket, &fdset);
 268                 int nRet = select(hSocket + 1, &fdset, nullptr, nullptr, &tval);
 269                 if (nRet == SOCKET_ERROR) {
 270                     return IntrRecvError::NetworkError;
 271                 }
 272             } else {
 273                 return IntrRecvError::NetworkError;
 274             }
 275         }
 276         if (interruptSocks5Recv)
 277             return IntrRecvError::Interrupted;
 278         curTime = GetTimeMillis();
 279     }
 280     return len == 0 ? IntrRecvError::OK : IntrRecvError::Timeout;
 281 }
 282
 283 /** Credentials for proxy authentication */
 284 struct ProxyCredentials
 285 {
 286     std::string username;
 287     std::string password;
 288 };
 289
 290 /** Convert SOCKS5 reply to an error message */
 291 std::string Socks5ErrorString(uint8_t err)
 292 {
 293     switch(err) {
 294         case SOCKS5Reply::GENFAILURE:
 295             return "general failure";
 296         case SOCKS5Reply::NOTALLOWED:
 297             return "connection not allowed";
 298         case SOCKS5Reply::NETUNREACHABLE:
 299             return "network unreachable";
 300         case SOCKS5Reply::HOSTUNREACHABLE:
 301             return "host unreachable";
 302         case SOCKS5Reply::CONNREFUSED:
 303             return "connection refused";
 304         case SOCKS5Reply::TTLEXPIRED:
 305             return "TTL expired";
 306         case SOCKS5Reply::CMDUNSUPPORTED:
 307             return "protocol error";
 308         case SOCKS5Reply::ATYPEUNSUPPORTED:
 309             return "address type not supported";
 310         default:
 311             return "unknown";
 312     }
 313 }
 314
 315 /** Connect using SOCKS5 (as described in RFC1928) */
 316 static bool Socks5(const std::string& strDest, int port, const ProxyCredentials *auth, SOCKET& hSocket)
 317 {
 318     IntrRecvError recvr;
 319     LogPrint(BCLog::NET, "SOCKS5 connecting %s\n", strDest);
 320     if (strDest.size() > 255) {
 321         CloseSocket(hSocket);
 322         return error("Hostname too long");
 323     }
 324     // Accepted authentication methods
 325     std::vector<uint8_t> vSocks5Init;
 326     vSocks5Init.push_back(SOCKSVersion::SOCKS5);
 327     if (auth) {
 328         vSocks5Init.push_back(0x02); // Number of methods
 329         vSocks5Init.push_back(SOCKS5Method::NOAUTH);
 330         vSocks5Init.push_back(SOCKS5Method::USER_PASS);
 331     } else {
 332         vSocks5Init.push_back(0x01); // Number of methods
 333         vSocks5Init.push_back(SOCKS5Method::NOAUTH);
 334     }
 335     ssize_t ret = send(hSocket, (const char*)vSocks5Init.data(), vSocks5Init.size(), MSG_NOSIGNAL);
 336     if (ret != (ssize_t)vSocks5Init.size()) {
 337         CloseSocket(hSocket);
 338         return error("Error sending to proxy");
 339     }
 340     uint8_t pchRet1[2];
 341     if ((recvr = InterruptibleRecv(pchRet1, 2, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) {
 342         CloseSocket(hSocket);
 343         LogPrintf("Socks5() connect to %s:%d failed: InterruptibleRecv() timeout or other failure\n", strDest, port);
 344         return false;
 345     }
 346     if (pchRet1[0] != SOCKSVersion::SOCKS5) {
 347         CloseSocket(hSocket);
 348         return error("Proxy failed to initialize");
 349     }
 350     if (pchRet1[1] == SOCKS5Method::USER_PASS && auth) {
 351         // Perform username/password authentication (as described in RFC1929)
 352         std::vector<uint8_t> vAuth;
 353         vAuth.push_back(0x01); // Current (and only) version of user/pass subnegotiation
 354         if (auth->username.size() > 255 || auth->password.size() > 255)
 355             return error("Proxy username or password too long");
 356         vAuth.push_back(auth->username.size());
 357         vAuth.insert(vAuth.end(), auth->username.begin(), auth->username.end());
 358         vAuth.push_back(auth->password.size());
 359         vAuth.insert(vAuth.end(), auth->password.begin(), auth->password.end());
 360         ret = send(hSocket, (const char*)vAuth.data(), vAuth.size(), MSG_NOSIGNAL);
 361         if (ret != (ssize_t)vAuth.size()) {
 362             CloseSocket(hSocket);
 363             return error("Error sending authentication to proxy");
 364         }
 365         LogPrint(BCLog::PROXY, "SOCKS5 sending proxy authentication %s:%s\n", auth->username, auth->password);
 366         uint8_t pchRetA[2];
 367         if ((recvr = InterruptibleRecv(pchRetA, 2, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) {
 368             CloseSocket(hSocket);
 369             return error("Error reading proxy authentication response");
 370         }
 371         if (pchRetA[0] != 0x01 || pchRetA[1] != 0x00) {
 372             CloseSocket(hSocket);
 373             return error("Proxy authentication unsuccessful");
 374         }
 375     } else if (pchRet1[1] == SOCKS5Method::NOAUTH) {
 376         // Perform no authentication
 377     } else {
 378         CloseSocket(hSocket);
 379         return error("Proxy requested wrong authentication method %02x", pchRet1[1]);
 380     }
 381     std::vector<uint8_t> vSocks5;
 382     vSocks5.push_back(SOCKSVersion::SOCKS5); // VER protocol version
 383     vSocks5.push_back(SOCKS5Command::CONNECT); // CMD CONNECT
 384     vSocks5.push_back(0x00); // RSV Reserved must be 0
 385     vSocks5.push_back(SOCKS5Atyp::DOMAINNAME); // ATYP DOMAINNAME
 386     vSocks5.push_back(strDest.size()); // Length<=255 is checked at beginning of function
 387     vSocks5.insert(vSocks5.end(), strDest.begin(), strDest.end());
 388     vSocks5.push_back((port >> 8) & 0xFF);
 389     vSocks5.push_back((port >> 0) & 0xFF);
 390     ret = send(hSocket, (const char*)vSocks5.data(), vSocks5.size(), MSG_NOSIGNAL);
 391     if (ret != (ssize_t)vSocks5.size()) {
 392         CloseSocket(hSocket);
 393         return error("Error sending to proxy");
 394     }
 395     uint8_t pchRet2[4];
 396     if ((recvr = InterruptibleRecv(pchRet2, 4, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) {
 397         CloseSocket(hSocket);
 398         if (recvr == IntrRecvError::Timeout) {
 399             /* If a timeout happens here, this effectively means we timed out while connecting
 400              * to the remote node. This is very common for Tor, so do not print an
 401              * error message. */
 402             return false;
 403         } else {
 404             return error("Error while reading proxy response");
 405         }
 406     }
 407     if (pchRet2[0] != SOCKSVersion::SOCKS5) {
 408         CloseSocket(hSocket);
 409         return error("Proxy failed to accept request");
 410     }
 411     if (pchRet2[1] != SOCKS5Reply::SUCCEEDED) {
 412         // Failures to connect to a peer that are not proxy errors
 413         CloseSocket(hSocket);
 414         LogPrintf("Socks5() connect to %s:%d failed: %s\n", strDest, port, Socks5ErrorString(pchRet2[1]));
 415         return false;
 416     }
 417     if (pchRet2[2] != 0x00) { // Reserved field must be 0
 418         CloseSocket(hSocket);
 419         return error("Error: malformed proxy response");
 420     }
 421     uint8_t pchRet3[256];
 422     switch (pchRet2[3])
 423     {
 424         case SOCKS5Atyp::IPV4: recvr = InterruptibleRecv(pchRet3, 4, SOCKS5_RECV_TIMEOUT, hSocket); break;
 425         case SOCKS5Atyp::IPV6: recvr = InterruptibleRecv(pchRet3, 16, SOCKS5_RECV_TIMEOUT, hSocket); break;
 426         case SOCKS5Atyp::DOMAINNAME:
 427         {
 428             recvr = InterruptibleRecv(pchRet3, 1, SOCKS5_RECV_TIMEOUT, hSocket);
 429             if (recvr != IntrRecvError::OK) {
 430                 CloseSocket(hSocket);
 431                 return error("Error reading from proxy");
 432             }
 433             int nRecv = pchRet3[0];
 434             recvr = InterruptibleRecv(pchRet3, nRecv, SOCKS5_RECV_TIMEOUT, hSocket);
 435             break;
 436         }
 437         default: CloseSocket(hSocket); return error("Error: malformed proxy response");
 438     }
 439     if (recvr != IntrRecvError::OK) {
 440         CloseSocket(hSocket);
 441         return error("Error reading from proxy");
 442     }
 443     if ((recvr = InterruptibleRecv(pchRet3, 2, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) {
 444         CloseSocket(hSocket);
 445         return error("Error reading from proxy");
 446     }
 447     LogPrint(BCLog::NET, "SOCKS5 connected %s\n", strDest);
 448     return true;
 449 }
 450
 451 bool ConnectSocketDirectly(const CService &addrConnect, SOCKET& hSocketRet, int nTimeout)
 452 {
 453     hSocketRet = INVALID_SOCKET;
 454
 455     struct sockaddr_storage sockaddr;
 456     socklen_t len = sizeof(sockaddr);
 457     if (!addrConnect.GetSockAddr((struct sockaddr*)&sockaddr, &len)) {
 458         LogPrintf("Cannot connect to %s: unsupported network\n", addrConnect.ToString());
 459         return false;
 460     }
 461
 462     SOCKET hSocket = socket(((struct sockaddr*)&sockaddr)->sa_family, SOCK_STREAM, IPPROTO_TCP);
 463     if (hSocket == INVALID_SOCKET)
 464         return false;
 465
 466 #ifdef SO_NOSIGPIPE
 467     int set = 1;
 468     // Different way of disabling SIGPIPE on BSD
 469     setsockopt(hSocket, SOL_SOCKET, SO_NOSIGPIPE, (void*)&set, sizeof(int));
 470 #endif
 471
 472     //Disable Nagle's algorithm
 473     SetSocketNoDelay(hSocket);
 474
 475     // Set to non-blocking
 476     if (!SetSocketNonBlocking(hSocket, true)) {
 477         CloseSocket(hSocket);
 478         return error("ConnectSocketDirectly: Setting socket to non-blocking failed, error %s\n", NetworkErrorString(WSAGetLastError()));
 479     }
 480
 481     if (connect(hSocket, (struct sockaddr*)&sockaddr, len) == SOCKET_ERROR)
 482     {
 483         int nErr = WSAGetLastError();
 484         // WSAEINVAL is here because some legacy version of winsock uses it
 485         if (nErr == WSAEINPROGRESS || nErr == WSAEWOULDBLOCK || nErr == WSAEINVAL)
 486         {
 487             struct timeval timeout = MillisToTimeval(nTimeout);
 488             fd_set fdset;
 489             FD_ZERO(&fdset);
 490             FD_SET(hSocket, &fdset);
 491             int nRet = select(hSocket + 1, nullptr, &fdset, nullptr, &timeout);
 492             if (nRet == 0)
 493             {
 494                 LogPrint(BCLog::NET, "connection to %s timeout\n", addrConnect.ToString());
 495                 CloseSocket(hSocket);
 496                 return false;
 497             }
 498             if (nRet == SOCKET_ERROR)
 499             {
 500                 LogPrintf("select() for %s failed: %s\n", addrConnect.ToString(), NetworkErrorString(WSAGetLastError()));
 501                 CloseSocket(hSocket);
 502                 return false;
 503             }
 504             socklen_t nRetSize = sizeof(nRet);
 505 #ifdef WIN32
 506             if (getsockopt(hSocket, SOL_SOCKET, SO_ERROR, (char*)(&nRet), &nRetSize) == SOCKET_ERROR)
 507 #else
 508             if (getsockopt(hSocket, SOL_SOCKET, SO_ERROR, &nRet, &nRetSize) == SOCKET_ERROR)
 509 #endif
 510             {
 511                 LogPrintf("getsockopt() for %s failed: %s\n", addrConnect.ToString(), NetworkErrorString(WSAGetLastError()));
 512                 CloseSocket(hSocket);
 513                 return false;
 514             }
 515             if (nRet != 0)
 516             {
 517                 LogPrintf("connect() to %s failed after select(): %s\n", addrConnect.ToString(), NetworkErrorString(nRet));
 518                 CloseSocket(hSocket);
 519                 return false;
 520             }
 521         }
 522 #ifdef WIN32
 523         else if (WSAGetLastError() != WSAEISCONN)
 524 #else
 525         else
 526 #endif
 527         {
 528             LogPrintf("connect() to %s failed: %s\n", addrConnect.ToString(), NetworkErrorString(WSAGetLastError()));
 529             CloseSocket(hSocket);
 530             return false;
 531         }
 532     }
 533
 534     hSocketRet = hSocket;
 535     return true;
 536 }
 537
 538 bool SetProxy(enum Network net, const proxyType &addrProxy) {
 539     assert(net >= 0 && net < NET_MAX);
 540     if (!addrProxy.IsValid())
 541         return false;
 542     LOCK(cs_proxyInfos);
 543     proxyInfo[net] = addrProxy;
 544     return true;
 545 }
 546
 547 bool GetProxy(enum Network net, proxyType &proxyInfoOut) {
 548     assert(net >= 0 && net < NET_MAX);
 549     LOCK(cs_proxyInfos);
 550     if (!proxyInfo[net].IsValid())
 551         return false;
 552     proxyInfoOut = proxyInfo[net];
 553     return true;
 554 }
 555
 556 bool SetNameProxy(const proxyType &addrProxy) {
 557     if (!addrProxy.IsValid())
 558         return false;
 559     LOCK(cs_proxyInfos);
 560     nameProxy = addrProxy;
 561     return true;
 562 }
 563
 564 bool GetNameProxy(proxyType &nameProxyOut) {
 565     LOCK(cs_proxyInfos);
 566     if(!nameProxy.IsValid())
 567         return false;
 568     nameProxyOut = nameProxy;
 569     return true;
 570 }
 571
 572 bool HaveNameProxy() {
 573     LOCK(cs_proxyInfos);
 574     return nameProxy.IsValid();
 575 }
 576
 577 bool IsProxy(const CNetAddr &addr) {
 578     LOCK(cs_proxyInfos);
 579     for (int i = 0; i < NET_MAX; i++) {
 580         if (addr == (CNetAddr)proxyInfo[i].proxy)
 581             return true;
 582     }
 583     return false;
 584 }
 585
 586 bool ConnectThroughProxy(const proxyType &proxy, const std::string& strDest, int port, SOCKET& hSocketRet, int nTimeout, bool *outProxyConnectionFailed)
 587 {
 588     SOCKET hSocket = INVALID_SOCKET;
 589     // first connect to proxy server
 590     if (!ConnectSocketDirectly(proxy.proxy, hSocket, nTimeout)) {
 591         if (outProxyConnectionFailed)
 592             *outProxyConnectionFailed = true;
 593         return false;
 594     }
 595     // do socks negotiation
 596     if (proxy.randomize_credentials) {
 597         ProxyCredentials random_auth;
 598         static std::atomic_int counter(0);
 599         random_auth.username = random_auth.password = strprintf("%i", counter++);
 600         if (!Socks5(strDest, (unsigned short)port, &random_auth, hSocket))
 601             return false;
 602     } else {
 603         if (!Socks5(strDest, (unsigned short)port, 0, hSocket))
 604             return false;
 605     }
 606
 607     hSocketRet = hSocket;
 608     return true;
 609 }
 610 bool LookupSubNet(const char* pszName, CSubNet& ret)
 611 {
 612     std::string strSubnet(pszName);
 613     size_t slash = strSubnet.find_last_of('/');
 614     std::vector<CNetAddr> vIP;
 615
 616     std::string strAddress = strSubnet.substr(0, slash);
 617     if (LookupHost(strAddress.c_str(), vIP, 1, false))
 618     {
 619         CNetAddr network = vIP[0];
 620         if (slash != strSubnet.npos)
 621         {
 622             std::string strNetmask = strSubnet.substr(slash + 1);
 623             int32_t n;
 624             // IPv4 addresses start at offset 12, and first 12 bytes must match, so just offset n
 625             if (ParseInt32(strNetmask, &n)) { // If valid number, assume /24 syntax
 626                 ret = CSubNet(network, n);
 627                 return ret.IsValid();
 628             }
 629             else // If not a valid number, try full netmask syntax
 630             {
 631                 // Never allow lookup for netmask
 632                 if (LookupHost(strNetmask.c_str(), vIP, 1, false)) {
 633                     ret = CSubNet(network, vIP[0]);
 634                     return ret.IsValid();
 635                 }
 636             }
 637         }
 638         else
 639         {
 640             ret = CSubNet(network);
 641             return ret.IsValid();
 642         }
 643     }
 644     return false;
 645 }
 646
 647 #ifdef WIN32
 648 std::string NetworkErrorString(int err)
 649 {
 650     char buf[256];
 651     buf[0] = 0;
 652     if(FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_MAX_WIDTH_MASK,
 653             nullptr, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
 654             buf, sizeof(buf), nullptr))
 655     {
 656         return strprintf("%s (%d)", buf, err);
 657     }
 658     else
 659     {
 660         return strprintf("Unknown error (%d)", err);
 661     }
 662 }
 663 #else
 664 std::string NetworkErrorString(int err)
 665 {
 666     char buf[256];
 667     buf[0] = 0;
 668     /* Too bad there are two incompatible implementations of the
 669      * thread-safe strerror. */
 670     const char *s;
 671 #ifdef STRERROR_R_CHAR_P /* GNU variant can return a pointer outside the passed buffer */
 672     s = strerror_r(err, buf, sizeof(buf));
 673 #else /* POSIX variant always returns message in buffer */
 674     s = buf;
 675     if (strerror_r(err, buf, sizeof(buf)))
 676         buf[0] = 0;
 677 #endif
 678     return strprintf("%s (%d)", s, err);
 679 }
 680 #endif
 681
 682 bool CloseSocket(SOCKET& hSocket)
 683 {
 684     if (hSocket == INVALID_SOCKET)
 685         return false;
 686 #ifdef WIN32
 687     int ret = closesocket(hSocket);
 688 #else
 689     int ret = close(hSocket);
 690 #endif
 691     hSocket = INVALID_SOCKET;
 692     return ret != SOCKET_ERROR;
 693 }
 694
 695 bool SetSocketNonBlocking(const SOCKET& hSocket, bool fNonBlocking)
 696 {
 697     if (fNonBlocking) {
 698 #ifdef WIN32
 699         u_long nOne = 1;
 700         if (ioctlsocket(hSocket, FIONBIO, &nOne) == SOCKET_ERROR) {
 701 #else
 702         int fFlags = fcntl(hSocket, F_GETFL, 0);
 703         if (fcntl(hSocket, F_SETFL, fFlags | O_NONBLOCK) == SOCKET_ERROR) {
 704 #endif
 705             return false;
 706         }
 707     } else {
 708 #ifdef WIN32
 709         u_long nZero = 0;
 710         if (ioctlsocket(hSocket, FIONBIO, &nZero) == SOCKET_ERROR) {
 711 #else
 712         int fFlags = fcntl(hSocket, F_GETFL, 0);
 713         if (fcntl(hSocket, F_SETFL, fFlags & ~O_NONBLOCK) == SOCKET_ERROR) {
 714 #endif
 715             return false;
 716         }
 717     }
 718
 719     return true;
 720 }
 721
 722 bool SetSocketNoDelay(const SOCKET& hSocket)
 723 {
 724     int set = 1;
 725     int rc = setsockopt(hSocket, IPPROTO_TCP, TCP_NODELAY, (const char*)&set, sizeof(int));
 726     return rc == 0;
 727 }
 728
 729 void InterruptSocks5(bool interrupt)
 730 {
 731     interruptSocks5Recv = interrupt;
 732 }