src/anytun.cpp

   1 /*
   2  *  anytun
   3  *
   4  *  The secure anycast tunneling protocol (satp) defines a protocol used
   5  *  for communication between any combination of unicast and anycast
   6  *  tunnel endpoints.  It has less protocol overhead than IPSec in Tunnel
   7  *  mode and allows tunneling of every ETHER TYPE protocol (e.g.
   8  *  ethernet, ip, arp ...). satp directly includes cryptography and
   9  *  message authentication based on the methodes used by SRTP.  It is
  10  *  intended to deliver a generic, scaleable and secure solution for
  11  *  tunneling and relaying of packets of any protocol.
  12  *
  13  *
  14  *  Copyright (C) 2007-2009 Othmar Gsenger, Erwin Nindl,
  15  *                          Christian Pointner <satp@wirdorange.org>
  16  *
  17  *  This file is part of Anytun.
  18  *
  19  *  Anytun is free software: you can redistribute it and/or modify
  20  *  it under the terms of the GNU General Public License as published by
  21  *  the Free Software Foundation, either version 3 of the License, or
  22  *  any later version.
  23  *
  24  *  Anytun is distributed in the hope that it will be useful,
  25  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  *  GNU General Public License for more details.
  28  *
  29  *  You should have received a copy of the GNU General Public License
  30  *  along with anytun.  If not, see <http://www.gnu.org/licenses/>.
  31  */
  32
  33 #include <boost/bind.hpp>
  34 #include <boost/thread.hpp>
  35 #include <boost/assign.hpp>
  36 #include <iostream>
  37 #include <fstream>
  38
  39 #include "datatypes.h"
  40
  41 #include "log.h"
  42 #include "resolver.h"
  43 #include "buffer.h"
  44 #include "plainPacket.h"
  45 #include "encryptedPacket.h"
  46 #include "cipher.h"
  47 #include "keyDerivation.h"
  48 #include "authAlgo.h"
  49 #include "cipherFactory.h"
  50 #include "authAlgoFactory.h"
  51 #include "keyDerivationFactory.h"
  52 #include "signalController.h"
  53 #ifndef _MSC_VER
  54 # include "daemonService.h"
  55 #else
  56 # ifdef WIN_SERVICE
  57 #  include "win32/winService.h"
  58 # else
  59 #  include "nullDaemon.h"
  60 # endif
  61 #endif
  62 #include "packetSource.h"
  63 #include "tunDevice.h"
  64 #include "options.h"
  65 #include "seqWindow.h"
  66 #include "connectionList.h"
  67 #ifndef NO_ROUTING
  68 #include "routingTable.h"
  69 #include "networkAddress.h"
  70 #endif
  71
  72 #ifndef ANYTUN_NOSYNC
  73 #include "syncQueue.h"
  74 #include "syncCommand.h"
  75 #include "syncServer.h"
  76 #include "syncClient.h"
  77 #include "syncOnConnect.hpp"
  78 #endif
  79
  80 #include "cryptinit.hpp"
  81 #include "sysExec.h"
  82
  83 bool disableRouting = false;
  84
  85 void createConnection(const PacketSourceEndpoint& remote_end, window_size_t seqSize, mux_t mux)
  86 {
  87   SeqWindow* seq = new SeqWindow(seqSize);
  88   seq_nr_t seq_nr_=0;
  89   KeyDerivation* kd = KeyDerivationFactory::create(gOpt.getKdPrf());
  90   kd->init(gOpt.getKey(), gOpt.getSalt(), gOpt.getPassphrase());
  91   kd->setRole(gOpt.getRole());
  92   cLog.msg(Log::PRIO_NOTICE) << "added connection remote host " << remote_end;
  93
  94   ConnectionParam connparam((*kd), (*seq), seq_nr_, remote_end);
  95   gConnectionList.addConnection(connparam,mux);
  96 #ifndef ANYTUN_NOSYNC
  97   SyncCommand sc(gConnectionList,mux);
  98   gSyncQueue.push(sc);
  99 #endif
 100 }
 101
 102 void createConnectionResolver(PacketSourceResolverIt& it, window_size_t seqSize, mux_t mux)
 103 {
 104   createConnection(*it, seqSize, mux);
 105 }
 106
 107 void createConnectionError(const std::exception& e)
 108 {
 109   gSignalController.inject(SIGERROR, e.what());
 110 }
 111
 112 #ifndef ANYTUN_NOSYNC
 113 void syncConnector(const OptionHost& connto)
 114 {
 115   SyncClient sc(connto.addr, connto.port);
 116   sc.run();
 117 }
 118
 119 void syncListener()
 120 {
 121   try {
 122     SyncServer server(gOpt.getLocalSyncAddr(), gOpt.getLocalSyncPort(), boost::bind(syncOnConnect, _1));
 123     gSyncQueue.setSyncServerPtr(&server);
 124     server.run();
 125   } catch(std::runtime_error& e) {
 126     cLog.msg(Log::PRIO_ERROR) << "sync listener thread died due to an uncaught runtime_error: " << e.what();
 127   } catch(std::exception& e) {
 128     cLog.msg(Log::PRIO_ERROR) << "sync listener thread died due to an uncaught exception: " << e.what();
 129   }
 130 }
 131 #endif
 132
 133 void sender(TunDevice* dev, PacketSource* src)
 134 {
 135   if(!dev || !src) {
 136     cLog.msg(Log::PRIO_ERROR) << "sender thread died because either dev or src pointer is null";
 137     return;
 138   }
 139
 140   try {
 141     std::auto_ptr<Cipher> c(CipherFactory::create(gOpt.getCipher(), KD_OUTBOUND));
 142     std::auto_ptr<AuthAlgo> a(AuthAlgoFactory::create(gOpt.getAuthAlgo(), KD_OUTBOUND));
 143
 144     PlainPacket plain_packet(MAX_PACKET_LENGTH);
 145     EncryptedPacket encrypted_packet(MAX_PACKET_LENGTH, gOpt.getAuthTagLength());
 146
 147     uint16_t mux = gOpt.getMux();
 148     PacketSourceEndpoint emptyEndpoint;
 149     while(1) {
 150       plain_packet.setLength(MAX_PACKET_LENGTH);
 151       encrypted_packet.withAuthTag(false);
 152       encrypted_packet.setLength(MAX_PACKET_LENGTH);
 153
 154       // read packet from device
 155       int len = dev->read(plain_packet.getPayload(), plain_packet.getPayloadLength());
 156       if(len < 0) {
 157         continue;  // silently ignore device read errors, this is probably no good idea...
 158       }
 159
 160       if(static_cast<uint32_t>(len) < PlainPacket::getHeaderLength()) {
 161         continue;  // ignore short packets
 162       }
 163       plain_packet.setPayloadLength(len);
 164       // set payload type
 165       if(dev->getType() == TYPE_TUN) {
 166         plain_packet.setPayloadType(PAYLOAD_TYPE_TUN);
 167       } else if(dev->getType() == TYPE_TAP) {
 168         plain_packet.setPayloadType(PAYLOAD_TYPE_TAP);
 169       } else {
 170         plain_packet.setPayloadType(0);
 171       }
 172
 173       if(gConnectionList.empty()) {
 174         continue;
 175       }
 176       //std::cout << "got Packet for plain "<<plain_packet.getDstAddr().toString();
 177       ConnectionMap::iterator cit;
 178 #ifndef NO_ROUTING
 179       if(!disableRouting)
 180         try {
 181           mux = gRoutingTable.getRoute(plain_packet.getDstAddr());
 182           //std::cout << " -> "<<mux << std::endl;
 183           cit = gConnectionList.getConnection(mux);
 184         } catch(std::exception&) { continue; }  // no route
 185       else {
 186         cit = gConnectionList.getBegin();
 187       }
 188 #else
 189       cit = gConnectionList.getBegin();
 190 #endif
 191
 192       if(cit==gConnectionList.getEnd()) {
 193         continue;  //no connection
 194       }
 195       ConnectionParam& conn = cit->second;
 196
 197       if(conn.remote_end_ == emptyEndpoint) {
 198         //cLog.msg(Log::PRIO_INFO) << "no remote address set";
 199         continue;
 200       }
 201
 202       // encrypt packet
 203       c->encrypt(conn.kd_, plain_packet, encrypted_packet, conn.seq_nr_, gOpt.getSenderId(), mux);
 204
 205       encrypted_packet.setHeader(conn.seq_nr_, gOpt.getSenderId(), mux);
 206       conn.seq_nr_++;
 207
 208       // add authentication tag
 209       a->generate(conn.kd_, encrypted_packet);
 210
 211       try {
 212         src->send(encrypted_packet.getBuf(), encrypted_packet.getLength(), conn.remote_end_);
 213       } catch(std::exception& /*e*/) {
 214         //TODO: do something here
 215         //cLog.msg(Log::PRIO_ERROR) << "could not send data: " << e.what();
 216       }
 217     }
 218   } catch(std::runtime_error& e) {
 219     cLog.msg(Log::PRIO_ERROR) << "sender thread died due to an uncaught runtime_error: " << e.what();
 220   } catch(std::exception& e) {
 221     cLog.msg(Log::PRIO_ERROR) << "sender thread died due to an uncaught exception: " << e.what();
 222   }
 223 }
 224
 225 void receiver(TunDevice* dev, PacketSource* src)
 226 {
 227   if(!dev || !src) {
 228     cLog.msg(Log::PRIO_ERROR) << "receiver thread died because either dev or src pointer is null";
 229     return;
 230   }
 231
 232   try {
 233     std::auto_ptr<Cipher> c(CipherFactory::create(gOpt.getCipher(), KD_INBOUND));
 234     std::auto_ptr<AuthAlgo> a(AuthAlgoFactory::create(gOpt.getAuthAlgo(), KD_INBOUND));
 235
 236     uint32_t auth_tag_length = gOpt.getAuthTagLength();
 237     EncryptedPacket encrypted_packet(MAX_PACKET_LENGTH, auth_tag_length);
 238     PlainPacket plain_packet(MAX_PACKET_LENGTH);
 239
 240     while(1) {
 241       PacketSourceEndpoint remote_end;
 242
 243       plain_packet.setLength(MAX_PACKET_LENGTH);
 244       encrypted_packet.withAuthTag(false);
 245       encrypted_packet.setLength(MAX_PACKET_LENGTH);
 246
 247       // read packet from socket
 248       int len;
 249       try {
 250         len = src->recv(encrypted_packet.getBuf(), encrypted_packet.getLength(), remote_end);
 251       } catch(std::exception& /*e*/) {
 252         //TODO: do something here
 253         //cLog.msg(Log::PRIO_ERROR) << "could not recive packet "<< e.what();
 254         continue;
 255       }
 256       if(len < 0) {
 257         continue;  // silently ignore socket recv errors, this is probably no good idea...
 258       }
 259
 260       if(static_cast<uint32_t>(len) < (EncryptedPacket::getHeaderLength() + auth_tag_length)) {
 261         continue;  // ignore short packets
 262       }
 263       encrypted_packet.setLength(len);
 264
 265       mux_t mux = encrypted_packet.getMux();
 266       // autodetect peer
 267       if(gConnectionList.empty() && gOpt.getRemoteAddr() == "") {
 268         cLog.msg(Log::PRIO_NOTICE) << "autodetected remote host " << remote_end;
 269         createConnection(remote_end, gOpt.getSeqWindowSize(),mux);
 270       }
 271
 272       ConnectionMap::iterator cit = gConnectionList.getConnection(mux);
 273       if(cit == gConnectionList.getEnd()) {
 274         continue;
 275       }
 276       ConnectionParam& conn = cit->second;
 277
 278       // check whether auth tag is ok or not
 279       if(!a->checkTag(conn.kd_, encrypted_packet)) {
 280         cLog.msg(Log::PRIO_NOTICE) << "wrong Authentication Tag!";
 281         continue;
 282       }
 283
 284       // Replay Protection
 285       if(conn.seq_window_.checkAndAdd(encrypted_packet.getSenderId(), encrypted_packet.getSeqNr())) {
 286         cLog.msg(Log::PRIO_NOTICE) << "Replay attack from " << conn.remote_end_
 287                                    << " seq:"<< encrypted_packet.getSeqNr() << " sid: "<< encrypted_packet.getSenderId();
 288         continue;
 289       }
 290
 291       //Allow dynamic IP changes
 292       //TODO: add command line option to turn this off
 293       if(remote_end != conn.remote_end_) {
 294         cLog.msg(Log::PRIO_NOTICE) << "connection "<< mux << " autodetected remote host ip changed " << remote_end;
 295         conn.remote_end_=remote_end;
 296 #ifndef ANYTUN_NOSYNC
 297         SyncCommand sc(gConnectionList,mux);
 298         gSyncQueue.push(sc);
 299 #endif
 300       }
 301       // ignore zero length packets
 302       if(encrypted_packet.getPayloadLength() <= PlainPacket::getHeaderLength()) {
 303         continue;
 304       }
 305
 306       // decrypt packet
 307       c->decrypt(conn.kd_, encrypted_packet, plain_packet);
 308
 309       // check payload_type
 310       if((dev->getType() == TYPE_TUN && plain_packet.getPayloadType() != PAYLOAD_TYPE_TUN4 &&
 311           plain_packet.getPayloadType() != PAYLOAD_TYPE_TUN6) ||
 312           (dev->getType() == TYPE_TAP && plain_packet.getPayloadType() != PAYLOAD_TYPE_TAP)) {
 313         continue;
 314       }
 315
 316       // write it on the device
 317       dev->write(plain_packet.getPayload(), plain_packet.getLength());
 318     }
 319   } catch(std::runtime_error& e) {
 320     cLog.msg(Log::PRIO_ERROR) << "receiver thread died due to an uncaught runtime_error: " << e.what();
 321   } catch(std::exception& e) {
 322     cLog.msg(Log::PRIO_ERROR) << "receiver thread died due to an uncaught exception: " << e.what();
 323   }
 324 }
 325
 326 void startSendRecvThreads(TunDevice* dev, PacketSource* src)
 327 {
 328   src->waitUntilReady();
 329
 330   boost::thread(boost::bind(sender, dev, src));
 331   boost::thread(boost::bind(receiver, dev, src));
 332 }
 333
 334
 335 #ifdef WIN_SERVICE
 336 int main(int argc, char* argv[])
 337 {
 338   try {
 339     if(argc > 1) {
 340       if(std::string(argv[1]) == "install") {
 341         WinService::install();
 342         return 0;
 343       } else if(std::string(argv[1]) == "uninstall") {
 344         WinService::uninstall();
 345         return 0;
 346       }
 347     }
 348     WinService::start();
 349     return 0;
 350   } catch(std::runtime_error& e) {
 351     std::cout << "caught runtime error, exiting: " << e.what() << std::endl;
 352   } catch(std::exception& e) {
 353     std::cout << "caught exception, exiting: " << e.what() << std::endl;
 354   }
 355 }
 356
 357 int real_main(int argc, char* argv[], WinService& service)
 358 {
 359 #else
 360 int main(int argc, char* argv[])
 361 {
 362   DaemonService service;
 363 #endif
 364   try {
 365     try {
 366       if(!gOpt.parse(argc, argv)) {
 367         exit(0);
 368       }
 369
 370       StringList targets = gOpt.getLogTargets();
 371       for(StringList::const_iterator it = targets.begin(); it != targets.end(); ++it) {
 372         cLog.addTarget(*it);
 373       }
 374     } catch(syntax_error& e) {
 375       std::cerr << e << std::endl;
 376       gOpt.printUsage();
 377       exit(-1);
 378     }
 379
 380     cLog.msg(Log::PRIO_NOTICE) << "anytun started...";
 381     gOpt.parse_post(); // print warnings
 382
 383     // daemonizing has to done before any thread gets started
 384     service.initPrivs(gOpt.getUsername(), gOpt.getGroupname());
 385     if(gOpt.getDaemonize()) {
 386       service.daemonize();
 387     }
 388
 389     OptionNetwork net = gOpt.getIfconfigParam();
 390     TunDevice dev(gOpt.getDevName(), gOpt.getDevType(), net.net_addr, net.prefix_length);
 391     cLog.msg(Log::PRIO_NOTICE) << "dev opened - name '" << dev.getActualName() << "', node '" << dev.getActualNode() << "'";
 392     cLog.msg(Log::PRIO_NOTICE) << "dev type is '" << dev.getTypeString() << "'";
 393
 394     SysExec* postup_script = NULL;
 395     if(gOpt.getPostUpScript() != "") {
 396       cLog.msg(Log::PRIO_NOTICE) << "executing post-up script '" << gOpt.getPostUpScript() << "'";
 397       StringVector args = boost::assign::list_of(dev.getActualName())(dev.getActualNode());
 398       postup_script = new SysExec(gOpt.getPostUpScript(), args);
 399     }
 400
 401     if(gOpt.getChrootDir() != "") {
 402       try {
 403         service.chroot(gOpt.getChrootDir());
 404       } catch(const std::runtime_error& e) {
 405         cLog.msg(Log::PRIO_WARNING) << "ignoring chroot error: " << e.what();
 406       }
 407     }
 408     service.dropPrivs();
 409
 410     // this has to be called before the first thread is started
 411     gSignalController.init(service);
 412     gResolver.init();
 413     boost::thread(boost::bind(&TunDevice::waitUntilReady,&dev));
 414     if(postup_script) {
 415       boost::thread(boost::bind(&SysExec::waitAndDestroy,postup_script));
 416     }
 417
 418     initCrypto();
 419
 420     PacketSource* src = new UDPPacketSource(gOpt.getLocalAddr(), gOpt.getLocalPort());
 421
 422     if(gOpt.getRemoteAddr() != "") {
 423       gResolver.resolveUdp(gOpt.getRemoteAddr(), gOpt.getRemotePort(), boost::bind(createConnectionResolver, _1, gOpt.getSeqWindowSize(), gOpt.getMux()), boost::bind(createConnectionError, _1), gOpt.getResolvAddrType());
 424     }
 425
 426     HostList connect_to = gOpt.getRemoteSyncHosts();
 427 #ifndef NO_ROUTING
 428     NetworkList routes = gOpt.getRoutes();
 429     NetworkList::const_iterator rit;
 430     for(rit = routes.begin(); rit != routes.end(); ++rit) {
 431       NetworkAddress addr(rit->net_addr);
 432       NetworkPrefix prefix(addr, static_cast<uint8_t>(rit->prefix_length));
 433       gRoutingTable.addRoute(prefix, gOpt.getMux());
 434     }
 435     if(connect_to.begin() == connect_to.end() || gOpt.getDevType()!="tun") {
 436       cLog.msg(Log::PRIO_NOTICE) << "No sync/control host defined or not a tun device. Disabling multi connection support (routing)";
 437       disableRouting=true;
 438     }
 439 #endif
 440
 441 #ifndef ANYTUN_NOSYNC
 442     boost::thread* syncListenerThread = NULL;
 443     if(gOpt.getLocalSyncPort() != "") {
 444       syncListenerThread = new boost::thread(boost::bind(syncListener));
 445     }
 446
 447     boost::thread_group connectThreads;
 448     for(HostList::const_iterator it = connect_to.begin() ; it != connect_to.end(); ++it) {
 449       connectThreads.create_thread(boost::bind(syncConnector, *it));
 450     }
 451 #endif
 452
 453     // wait for packet source to finish in a seperate thread in order
 454     // to be still able to process signals while waiting
 455     boost::thread(boost::bind(startSendRecvThreads, &dev, src));
 456
 457     int ret = gSignalController.run();
 458
 459     // TODO: stop all threads and cleanup
 460     //
 461     //     if(src)
 462     //       delete src;
 463     //     if(connTo)
 464     //       delete connTo;
 465     return ret;
 466   } catch(std::runtime_error& e) {
 467     cLog.msg(Log::PRIO_ERROR) << "uncaught runtime error, exiting: " << e.what();
 468     if(!service.isDaemonized()) {
 469       std::cout << "uncaught runtime error, exiting: " << e.what() << std::endl;
 470     }
 471   } catch(std::exception& e) {
 472     cLog.msg(Log::PRIO_ERROR) << "uncaught exception, exiting: " << e.what();
 473     if(!service.isDaemonized()) {
 474       std::cout << "uncaught exception, exiting: " << e.what() << std::endl;
 475     }
 476   }
 477   return -1;
 478 }
 479
 480