diff --git a/src/netbase.cpp b/src/netbase.cpp index 19ab2d220..10b1f5124 100644 --- a/src/netbase.cpp +++ b/src/netbase.cpp @@ -1,785 +1,788 @@ // Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2016 The Bitcoin Core developers // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #include #include #include #include #include #include #include #include #ifndef WIN32 #include #endif #if !defined(MSG_NOSIGNAL) #define MSG_NOSIGNAL 0 #endif // Settings static proxyType proxyInfo[NET_MAX]; static proxyType nameProxy; static CCriticalSection cs_proxyInfos; int nConnectTimeout = DEFAULT_CONNECT_TIMEOUT; bool fNameLookup = DEFAULT_NAME_LOOKUP; // Need ample time for negotiation for very slow proxies such as Tor // (milliseconds) static const int SOCKS5_RECV_TIMEOUT = 20 * 1000; static std::atomic interruptSocks5Recv(false); enum Network ParseNetwork(std::string net) { Downcase(net); if (net == "ipv4") { return NET_IPV4; } if (net == "ipv6") { return NET_IPV6; } if (net == "onion") { return NET_ONION; } if (net == "tor") { LogPrintf("Warning: net name 'tor' is deprecated and will be removed " "in the future. You should use 'onion' instead.\n"); return NET_ONION; } return NET_UNROUTABLE; } std::string GetNetworkName(enum Network net) { switch (net) { case NET_IPV4: return "ipv4"; case NET_IPV6: return "ipv6"; case NET_ONION: return "onion"; default: return ""; } } static bool LookupIntern(const char *pszName, std::vector &vIP, unsigned int nMaxSolutions, bool fAllowLookup) { vIP.clear(); { CNetAddr addr; if (addr.SetSpecial(std::string(pszName))) { vIP.push_back(addr); return true; } } struct addrinfo aiHint; memset(&aiHint, 0, sizeof(struct addrinfo)); aiHint.ai_socktype = SOCK_STREAM; aiHint.ai_protocol = IPPROTO_TCP; aiHint.ai_family = AF_UNSPEC; #ifdef WIN32 aiHint.ai_flags = fAllowLookup ? 0 : AI_NUMERICHOST; #else aiHint.ai_flags = fAllowLookup ? AI_ADDRCONFIG : AI_NUMERICHOST; #endif struct addrinfo *aiRes = nullptr; int nErr = getaddrinfo(pszName, nullptr, &aiHint, &aiRes); if (nErr) { return false; } struct addrinfo *aiTrav = aiRes; while (aiTrav != nullptr && (nMaxSolutions == 0 || vIP.size() < nMaxSolutions)) { CNetAddr resolved; if (aiTrav->ai_family == AF_INET) { assert(aiTrav->ai_addrlen >= sizeof(sockaddr_in)); resolved = CNetAddr(reinterpret_cast(aiTrav->ai_addr) ->sin_addr); } if (aiTrav->ai_family == AF_INET6) { assert(aiTrav->ai_addrlen >= sizeof(sockaddr_in6)); struct sockaddr_in6 *s6 = reinterpret_cast(aiTrav->ai_addr); resolved = CNetAddr(s6->sin6_addr, s6->sin6_scope_id); } // Never allow resolving to an internal address. Consider any such // result invalid. if (!resolved.IsInternal()) { vIP.push_back(resolved); } aiTrav = aiTrav->ai_next; } freeaddrinfo(aiRes); return (vIP.size() > 0); } bool LookupHost(const char *pszName, std::vector &vIP, unsigned int nMaxSolutions, bool fAllowLookup) { std::string strHost(pszName); if (strHost.empty()) { return false; } if (strHost.front() == '[' && strHost.back() == ']') { strHost = strHost.substr(1, strHost.size() - 2); } return LookupIntern(strHost.c_str(), vIP, nMaxSolutions, fAllowLookup); } bool LookupHost(const char *pszName, CNetAddr &addr, bool fAllowLookup) { std::vector vIP; LookupHost(pszName, vIP, 1, fAllowLookup); if (vIP.empty()) { return false; } addr = vIP.front(); return true; } bool Lookup(const char *pszName, std::vector &vAddr, int portDefault, bool fAllowLookup, unsigned int nMaxSolutions) { if (pszName[0] == 0) { return false; } int port = portDefault; std::string hostname = ""; SplitHostPort(std::string(pszName), port, hostname); std::vector vIP; bool fRet = LookupIntern(hostname.c_str(), vIP, nMaxSolutions, fAllowLookup); if (!fRet) { return false; } vAddr.resize(vIP.size()); for (unsigned int i = 0; i < vIP.size(); i++) { vAddr[i] = CService(vIP[i], port); } return true; } bool Lookup(const char *pszName, CService &addr, int portDefault, bool fAllowLookup) { std::vector vService; bool fRet = Lookup(pszName, vService, portDefault, fAllowLookup, 1); if (!fRet) { return false; } addr = vService[0]; return true; } CService LookupNumeric(const char *pszName, int portDefault) { CService addr; // "1.2:345" will fail to resolve the ip, but will still set the port. // If the ip fails to resolve, re-init the result. if (!Lookup(pszName, addr, portDefault, false)) { addr = CService(); } return addr; } struct timeval MillisToTimeval(int64_t nTimeout) { struct timeval timeout; timeout.tv_sec = nTimeout / 1000; timeout.tv_usec = (nTimeout % 1000) * 1000; return timeout; } /** SOCKS version */ enum SOCKSVersion : uint8_t { SOCKS4 = 0x04, SOCKS5 = 0x05 }; /** Values defined for METHOD in RFC1928 */ enum SOCKS5Method : uint8_t { NOAUTH = 0x00, //! No authentication required GSSAPI = 0x01, //! GSSAPI USER_PASS = 0x02, //! Username/password NO_ACCEPTABLE = 0xff, //! No acceptable methods }; /** Values defined for CMD in RFC1928 */ enum SOCKS5Command : uint8_t { CONNECT = 0x01, BIND = 0x02, UDP_ASSOCIATE = 0x03 }; /** Values defined for REP in RFC1928 */ enum SOCKS5Reply : uint8_t { SUCCEEDED = 0x00, //! Succeeded GENFAILURE = 0x01, //! General failure NOTALLOWED = 0x02, //! Connection not allowed by ruleset NETUNREACHABLE = 0x03, //! Network unreachable HOSTUNREACHABLE = 0x04, //! Network unreachable CONNREFUSED = 0x05, //! Connection refused TTLEXPIRED = 0x06, //! TTL expired CMDUNSUPPORTED = 0x07, //! Command not supported ATYPEUNSUPPORTED = 0x08, //! Address type not supported }; /** Values defined for ATYPE in RFC1928 */ enum SOCKS5Atyp : uint8_t { IPV4 = 0x01, DOMAINNAME = 0x03, IPV6 = 0x04, }; /** Status codes that can be returned by InterruptibleRecv */ enum class IntrRecvError { OK, Timeout, Disconnected, NetworkError, Interrupted }; /** * Read bytes from socket. This will either read the full number of bytes * requested or return False on error or timeout. * This function can be interrupted by calling InterruptSocks5() * * @param data Buffer to receive into * @param len Length of data to receive * @param timeout Timeout in milliseconds for receive operation * * @note This function requires that hSocket is in non-blocking mode. */ static IntrRecvError InterruptibleRecv(uint8_t *data, size_t len, int timeout, const SOCKET &hSocket) { int64_t curTime = GetTimeMillis(); int64_t endTime = curTime + timeout; // Maximum time to wait in one select call. It will take up until this time // (in millis) to break off in case of an interruption. const int64_t maxWait = 1000; while (len > 0 && curTime < endTime) { // Optimistically try the recv first ssize_t ret = recv(hSocket, (char *)data, len, 0); if (ret > 0) { len -= ret; data += ret; } else if (ret == 0) { // Unexpected disconnection return IntrRecvError::Disconnected; } else { // Other error or blocking int nErr = WSAGetLastError(); if (nErr == WSAEINPROGRESS || nErr == WSAEWOULDBLOCK || nErr == WSAEINVAL) { if (!IsSelectableSocket(hSocket)) { return IntrRecvError::NetworkError; } struct timeval tval = MillisToTimeval(std::min(endTime - curTime, maxWait)); fd_set fdset; FD_ZERO(&fdset); FD_SET(hSocket, &fdset); int nRet = select(hSocket + 1, &fdset, nullptr, nullptr, &tval); if (nRet == SOCKET_ERROR) { return IntrRecvError::NetworkError; } } else { return IntrRecvError::NetworkError; } } if (interruptSocks5Recv) { return IntrRecvError::Interrupted; } curTime = GetTimeMillis(); } return len == 0 ? IntrRecvError::OK : IntrRecvError::Timeout; } /** Credentials for proxy authentication */ struct ProxyCredentials { std::string username; std::string password; }; /** Convert SOCKS5 reply to an error message */ static std::string Socks5ErrorString(uint8_t err) { switch (err) { case SOCKS5Reply::GENFAILURE: return "general failure"; case SOCKS5Reply::NOTALLOWED: return "connection not allowed"; case SOCKS5Reply::NETUNREACHABLE: return "network unreachable"; case SOCKS5Reply::HOSTUNREACHABLE: return "host unreachable"; case SOCKS5Reply::CONNREFUSED: return "connection refused"; case SOCKS5Reply::TTLEXPIRED: return "TTL expired"; case SOCKS5Reply::CMDUNSUPPORTED: return "protocol error"; case SOCKS5Reply::ATYPEUNSUPPORTED: return "address type not supported"; default: return "unknown"; } } /** Connect using SOCKS5 (as described in RFC1928) */ static bool Socks5(const std::string &strDest, int port, const ProxyCredentials *auth, const SOCKET &hSocket) { IntrRecvError recvr; LogPrint(BCLog::NET, "SOCKS5 connecting %s\n", strDest); if (strDest.size() > 255) { return error("Hostname too long"); } // Accepted authentication methods std::vector vSocks5Init; vSocks5Init.push_back(SOCKSVersion::SOCKS5); if (auth) { vSocks5Init.push_back(0x02); // Number of methods vSocks5Init.push_back(SOCKS5Method::NOAUTH); vSocks5Init.push_back(SOCKS5Method::USER_PASS); } else { vSocks5Init.push_back(0x01); // Number of methods vSocks5Init.push_back(SOCKS5Method::NOAUTH); } ssize_t ret = send(hSocket, (const char *)vSocks5Init.data(), vSocks5Init.size(), MSG_NOSIGNAL); if (ret != (ssize_t)vSocks5Init.size()) { return error("Error sending to proxy"); } uint8_t pchRet1[2]; if ((recvr = InterruptibleRecv(pchRet1, 2, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) { LogPrintf("Socks5() connect to %s:%d failed: InterruptibleRecv() " "timeout or other failure\n", strDest, port); return false; } if (pchRet1[0] != SOCKSVersion::SOCKS5) { return error("Proxy failed to initialize"); } if (pchRet1[1] == SOCKS5Method::USER_PASS && auth) { // Perform username/password authentication (as described in RFC1929) std::vector vAuth; // Current (and only) version of user/pass subnegotiation vAuth.push_back(0x01); if (auth->username.size() > 255 || auth->password.size() > 255) { return error("Proxy username or password too long"); } vAuth.push_back(auth->username.size()); vAuth.insert(vAuth.end(), auth->username.begin(), auth->username.end()); vAuth.push_back(auth->password.size()); vAuth.insert(vAuth.end(), auth->password.begin(), auth->password.end()); ret = send(hSocket, (const char *)vAuth.data(), vAuth.size(), MSG_NOSIGNAL); if (ret != (ssize_t)vAuth.size()) { return error("Error sending authentication to proxy"); } LogPrint(BCLog::PROXY, "SOCKS5 sending proxy authentication %s:%s\n", auth->username, auth->password); uint8_t pchRetA[2]; if ((recvr = InterruptibleRecv(pchRetA, 2, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) { return error("Error reading proxy authentication response"); } if (pchRetA[0] != 0x01 || pchRetA[1] != 0x00) { return error("Proxy authentication unsuccessful"); } } else if (pchRet1[1] == SOCKS5Method::NOAUTH) { // Perform no authentication } else { return error("Proxy requested wrong authentication method %02x", pchRet1[1]); } std::vector vSocks5; // VER protocol version vSocks5.push_back(SOCKSVersion::SOCKS5); // CMD CONNECT vSocks5.push_back(SOCKS5Command::CONNECT); // RSV Reserved must be 0 vSocks5.push_back(0x00); // ATYP DOMAINNAME vSocks5.push_back(SOCKS5Atyp::DOMAINNAME); // Length<=255 is checked at beginning of function vSocks5.push_back(strDest.size()); vSocks5.insert(vSocks5.end(), strDest.begin(), strDest.end()); vSocks5.push_back((port >> 8) & 0xFF); vSocks5.push_back((port >> 0) & 0xFF); ret = send(hSocket, (const char *)vSocks5.data(), vSocks5.size(), MSG_NOSIGNAL); if (ret != (ssize_t)vSocks5.size()) { return error("Error sending to proxy"); } uint8_t pchRet2[4]; if ((recvr = InterruptibleRecv(pchRet2, 4, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) { if (recvr == IntrRecvError::Timeout) { /** * If a timeout happens here, this effectively means we timed out * while connecting to the remote node. This is very common for Tor, * so do not print an error message. */ return false; } else { return error("Error while reading proxy response"); } } if (pchRet2[0] != SOCKSVersion::SOCKS5) { return error("Proxy failed to accept request"); } if (pchRet2[1] != SOCKS5Reply::SUCCEEDED) { // Failures to connect to a peer that are not proxy errors LogPrintf("Socks5() connect to %s:%d failed: %s\n", strDest, port, Socks5ErrorString(pchRet2[1])); return false; } // Reserved field must be 0 if (pchRet2[2] != 0x00) { return error("Error: malformed proxy response"); } uint8_t pchRet3[256]; switch (pchRet2[3]) { case SOCKS5Atyp::IPV4: recvr = InterruptibleRecv(pchRet3, 4, SOCKS5_RECV_TIMEOUT, hSocket); break; case SOCKS5Atyp::IPV6: recvr = InterruptibleRecv(pchRet3, 16, SOCKS5_RECV_TIMEOUT, hSocket); break; case SOCKS5Atyp::DOMAINNAME: { recvr = InterruptibleRecv(pchRet3, 1, SOCKS5_RECV_TIMEOUT, hSocket); if (recvr != IntrRecvError::OK) { return error("Error reading from proxy"); } int nRecv = pchRet3[0]; recvr = InterruptibleRecv(pchRet3, nRecv, SOCKS5_RECV_TIMEOUT, hSocket); break; } default: return error("Error: malformed proxy response"); } if (recvr != IntrRecvError::OK) { return error("Error reading from proxy"); } if ((recvr = InterruptibleRecv(pchRet3, 2, SOCKS5_RECV_TIMEOUT, hSocket)) != IntrRecvError::OK) { return error("Error reading from proxy"); } LogPrint(BCLog::NET, "SOCKS5 connected %s\n", strDest); return true; } SOCKET CreateSocket(const CService &addrConnect) { struct sockaddr_storage sockaddr; socklen_t len = sizeof(sockaddr); if (!addrConnect.GetSockAddr((struct sockaddr *)&sockaddr, &len)) { LogPrintf("Cannot create socket for %s: unsupported network\n", addrConnect.ToString()); return INVALID_SOCKET; } SOCKET hSocket = socket(((struct sockaddr *)&sockaddr)->sa_family, SOCK_STREAM, IPPROTO_TCP); if (hSocket == INVALID_SOCKET) { return INVALID_SOCKET; } if (!IsSelectableSocket(hSocket)) { CloseSocket(hSocket); LogPrintf("Cannot create connection: non-selectable socket created (fd " ">= FD_SETSIZE ?)\n"); return INVALID_SOCKET; } #ifdef SO_NOSIGPIPE int set = 1; // Different way of disabling SIGPIPE on BSD setsockopt(hSocket, SOL_SOCKET, SO_NOSIGPIPE, (sockopt_arg_type)&set, sizeof(int)); #endif // Disable Nagle's algorithm SetSocketNoDelay(hSocket); // Set to non-blocking if (!SetSocketNonBlocking(hSocket, true)) { CloseSocket(hSocket); LogPrintf("ConnectSocketDirectly: Setting socket to non-blocking " "failed, error %s\n", NetworkErrorString(WSAGetLastError())); } return hSocket; } bool ConnectSocketDirectly(const CService &addrConnect, const SOCKET &hSocket, int nTimeout) { struct sockaddr_storage sockaddr; socklen_t len = sizeof(sockaddr); if (hSocket == INVALID_SOCKET) { LogPrintf("Cannot connect to %s: invalid socket\n", addrConnect.ToString()); return false; } if (!addrConnect.GetSockAddr((struct sockaddr *)&sockaddr, &len)) { LogPrintf("Cannot connect to %s: unsupported network\n", addrConnect.ToString()); return false; } if (connect(hSocket, (struct sockaddr *)&sockaddr, len) == SOCKET_ERROR) { int nErr = WSAGetLastError(); // WSAEINVAL is here because some legacy version of winsock uses it if (nErr == WSAEINPROGRESS || nErr == WSAEWOULDBLOCK || nErr == WSAEINVAL) { struct timeval timeout = MillisToTimeval(nTimeout); fd_set fdset; FD_ZERO(&fdset); FD_SET(hSocket, &fdset); int nRet = select(hSocket + 1, nullptr, &fdset, nullptr, &timeout); if (nRet == 0) { LogPrint(BCLog::NET, "connection to %s timeout\n", addrConnect.ToString()); return false; } if (nRet == SOCKET_ERROR) { LogPrintf("select() for %s failed: %s\n", addrConnect.ToString(), NetworkErrorString(WSAGetLastError())); return false; } socklen_t nRetSize = sizeof(nRet); if (getsockopt(hSocket, SOL_SOCKET, SO_ERROR, (sockopt_arg_type)&nRet, &nRetSize) == SOCKET_ERROR) { LogPrintf("getsockopt() for %s failed: %s\n", addrConnect.ToString(), NetworkErrorString(WSAGetLastError())); return false; } if (nRet != 0) { LogPrintf("connect() to %s failed after select(): %s\n", addrConnect.ToString(), NetworkErrorString(nRet)); return false; } } #ifdef WIN32 else if (WSAGetLastError() != WSAEISCONN) #else else #endif { LogPrintf("connect() to %s failed: %s\n", addrConnect.ToString(), NetworkErrorString(WSAGetLastError())); return false; } } return true; } bool SetProxy(enum Network net, const proxyType &addrProxy) { assert(net >= 0 && net < NET_MAX); if (!addrProxy.IsValid()) { return false; } LOCK(cs_proxyInfos); proxyInfo[net] = addrProxy; return true; } bool GetProxy(enum Network net, proxyType &proxyInfoOut) { assert(net >= 0 && net < NET_MAX); LOCK(cs_proxyInfos); if (!proxyInfo[net].IsValid()) { return false; } proxyInfoOut = proxyInfo[net]; return true; } bool SetNameProxy(const proxyType &addrProxy) { if (!addrProxy.IsValid()) { return false; } LOCK(cs_proxyInfos); nameProxy = addrProxy; return true; } bool GetNameProxy(proxyType &nameProxyOut) { LOCK(cs_proxyInfos); if (!nameProxy.IsValid()) { return false; } nameProxyOut = nameProxy; return true; } bool HaveNameProxy() { LOCK(cs_proxyInfos); return nameProxy.IsValid(); } bool IsProxy(const CNetAddr &addr) { LOCK(cs_proxyInfos); for (int i = 0; i < NET_MAX; i++) { if (addr == static_cast(proxyInfo[i].proxy)) { return true; } } return false; } bool ConnectThroughProxy(const proxyType &proxy, const std::string &strDest, int port, const SOCKET &hSocket, int nTimeout, bool *outProxyConnectionFailed) { // first connect to proxy server if (!ConnectSocketDirectly(proxy.proxy, hSocket, nTimeout)) { if (outProxyConnectionFailed) { *outProxyConnectionFailed = true; } return false; } // do socks negotiation if (proxy.randomize_credentials) { ProxyCredentials random_auth; static std::atomic_int counter(0); random_auth.username = random_auth.password = strprintf("%i", counter++); if (!Socks5(strDest, (unsigned short)port, &random_auth, hSocket)) { return false; } } else if (!Socks5(strDest, (unsigned short)port, 0, hSocket)) { return false; } return true; } bool LookupSubNet(const char *pszName, CSubNet &ret) { std::string strSubnet(pszName); size_t slash = strSubnet.find_last_of('/'); std::vector vIP; std::string strAddress = strSubnet.substr(0, slash); if (LookupHost(strAddress.c_str(), vIP, 1, false)) { CNetAddr network = vIP[0]; if (slash != strSubnet.npos) { std::string strNetmask = strSubnet.substr(slash + 1); int32_t n; // IPv4 addresses start at offset 12, and first 12 bytes must match, // so just offset n if (ParseInt32(strNetmask, &n)) { // If valid number, assume /24 syntax ret = CSubNet(network, n); return ret.IsValid(); } else { // If not a valid number, try full netmask syntax // Never allow lookup for netmask if (LookupHost(strNetmask.c_str(), vIP, 1, false)) { ret = CSubNet(network, vIP[0]); return ret.IsValid(); } } } else { ret = CSubNet(network); return ret.IsValid(); } } return false; } #ifdef WIN32 std::string NetworkErrorString(int err) { char buf[256]; buf[0] = 0; if (FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_MAX_WIDTH_MASK, nullptr, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, sizeof(buf), nullptr)) { return strprintf("%s (%d)", buf, err); } else { return strprintf("Unknown error (%d)", err); } } #else std::string NetworkErrorString(int err) { char buf[256]; - const char *s = buf; buf[0] = 0; -/* Too bad there are two incompatible implementations of the - * thread-safe strerror. */ + /** + * Too bad there are two incompatible implementations of the + * thread-safe strerror. + */ + const char *s; #ifdef STRERROR_R_CHAR_P /* GNU variant can return a pointer outside the passed buffer */ s = strerror_r(err, buf, sizeof(buf)); #else + s = buf; /* POSIX variant always returns message in buffer */ if (strerror_r(err, buf, sizeof(buf))) { buf[0] = 0; } #endif return strprintf("%s (%d)", s, err); } #endif bool CloseSocket(SOCKET &hSocket) { if (hSocket == INVALID_SOCKET) { return false; } #ifdef WIN32 int ret = closesocket(hSocket); #else int ret = close(hSocket); #endif if (ret) { LogPrintf("Socket close failed: %d. Error: %s\n", hSocket, NetworkErrorString(WSAGetLastError())); } hSocket = INVALID_SOCKET; return ret != SOCKET_ERROR; } bool SetSocketNonBlocking(const SOCKET &hSocket, bool fNonBlocking) { if (fNonBlocking) { #ifdef WIN32 u_long nOne = 1; if (ioctlsocket(hSocket, FIONBIO, &nOne) == SOCKET_ERROR) { #else int fFlags = fcntl(hSocket, F_GETFL, 0); if (fcntl(hSocket, F_SETFL, fFlags | O_NONBLOCK) == SOCKET_ERROR) { #endif return false; } } else { #ifdef WIN32 u_long nZero = 0; if (ioctlsocket(hSocket, FIONBIO, &nZero) == SOCKET_ERROR) { #else int fFlags = fcntl(hSocket, F_GETFL, 0); if (fcntl(hSocket, F_SETFL, fFlags & ~O_NONBLOCK) == SOCKET_ERROR) { #endif return false; } } return true; } bool SetSocketNoDelay(const SOCKET &hSocket) { int set = 1; int rc = setsockopt(hSocket, IPPROTO_TCP, TCP_NODELAY, (sockopt_arg_type)&set, sizeof(int)); return rc == 0; } void InterruptSocks5(bool interrupt) { interruptSocks5Recv = interrupt; }