pdns/ixfrdist.cc

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25 #include <boost/program_options.hpp>
  26 #include <arpa/inet.h>
  27 #include <sys/types.h>
  28 #include <grp.h>
  29 #include <pwd.h>
  30 #include <sys/stat.h>
  31 #include <mutex>
  32 #include <thread>
  33 #include <dirent.h>
  34 #include <queue>
  35 #include <condition_variable>
  36 #include "ixfr.hh"
  37 #include "ixfrutils.hh"
  38 #include "resolver.hh"
  39 #include "dns_random.hh"
  40 #include "sstuff.hh"
  41 #include "mplexer.hh"
  42 #include "misc.hh"
  43 #include "iputils.hh"
  44 #include "logger.hh"
  45 #include <yaml-cpp/yaml.h>
  46
  47 /* BEGIN Needed because of deeper dependencies */
  48 #include "arguments.hh"
  49 #include "statbag.hh"
  50 StatBag S;
  51
  52 ArgvMap &arg()
  53 {
  54   static ArgvMap theArg;
  55   return theArg;
  56 }
  57 /* END Needed because of deeper dependencies */
  58
  59 // Allows reading/writing ComboAddresses and DNSNames in YAML-cpp
  60 namespace YAML {
  61 template<>
  62 struct convert<ComboAddress> {
  63   static Node encode(const ComboAddress& rhs) {
  64     return Node(rhs.toStringWithPort());
  65   }
  66   static bool decode(const Node& node, ComboAddress& rhs) {
  67     if (!node.IsScalar()) {
  68       return false;
  69     }
  70     try {
  71       rhs = ComboAddress(node.as<string>(), 53);
  72       return true;
  73     } catch(const runtime_error &e) {
  74       return false;
  75     } catch (const PDNSException &e) {
  76       return false;
  77     }
  78   }
  79 };
  80
  81 template<>
  82 struct convert<DNSName> {
  83   static Node encode(const DNSName& rhs) {
  84     return Node(rhs.toStringRootDot());
  85   }
  86   static bool decode(const Node& node, DNSName& rhs) {
  87     if (!node.IsScalar()) {
  88       return false;
  89     }
  90     try {
  91       rhs = DNSName(node.as<string>());
  92       return true;
  93     } catch(const runtime_error &e) {
  94       return false;
  95     } catch (const PDNSException &e) {
  96       return false;
  97     }
  98   }
  99 };
 100 } // namespace YAML
 101
 102 struct ixfrdiff_t {
 103   shared_ptr<SOARecordContent> oldSOA;
 104   shared_ptr<SOARecordContent> newSOA;
 105   vector<DNSRecord> removals;
 106   vector<DNSRecord> additions;
 107 };
 108
 109 struct ixfrinfo_t {
 110   shared_ptr<SOARecordContent> soa; // The SOA of the latestAXFR
 111   records_t latestAXFR;             // The most recent AXFR
 112   vector<std::shared_ptr<ixfrdiff_t>> ixfrDiffs;
 113 };
 114
 115 // Why a struct? This way we can add more options to a domain in the future
 116 struct ixfrdistdomain_t {
 117   set<ComboAddress> masters; // A set so we can do multiple master addresses in the future
 118 };
 119
 120 // This contains the configuration for each domain
 121 static map<DNSName, ixfrdistdomain_t> g_domainConfigs;
 122
 123 // Map domains and their data
 124 static std::map<DNSName, std::shared_ptr<ixfrinfo_t>> g_soas;
 125 static std::mutex g_soas_mutex;
 126
 127 // Condition variable for TCP handling
 128 static std::condition_variable g_tcpHandlerCV;
 129 static std::queue<pair<int, ComboAddress>> g_tcpRequestFDs;
 130 static std::mutex g_tcpRequestFDsMutex;
 131
 132 namespace po = boost::program_options;
 133
 134 static bool g_exiting = false;
 135
 136 static NetmaskGroup g_acl;
 137 static bool g_compress = false;
 138
 139 static void handleSignal(int signum) {
 140   g_log<<Logger::Notice<<"Got "<<strsignal(signum)<<" signal";
 141   if (g_exiting) {
 142     g_log<<Logger::Notice<<", this is the second time we were asked to stop, forcefully exiting"<<endl;
 143     exit(EXIT_FAILURE);
 144   }
 145   g_log<<Logger::Notice<<", stopping, this may take a few second due to in-progress transfers and cleanup. Send this signal again to forcefully stop"<<endl;
 146   g_exiting = true;
 147 }
 148
 149 static void usage(po::options_description &desc) {
 150   cerr << "Usage: ixfrdist [OPTION]..."<<endl;
 151   cerr << desc << "\n";
 152 }
 153
 154 // The compiler does not like using rfc1982LessThan in std::sort directly
 155 static bool sortSOA(uint32_t i, uint32_t j) {
 156   return rfc1982LessThan(i, j);
 157 }
 158
 159 static void cleanUpDomain(const DNSName& domain, const uint16_t& keep, const string& workdir) {
 160   string dir = workdir + "/" + domain.toString();
 161   DIR *dp;
 162   dp = opendir(dir.c_str());
 163   if (dp == nullptr) {
 164     return;
 165   }
 166   vector<uint32_t> zoneVersions;
 167   struct dirent *d;
 168   while ((d = readdir(dp)) != nullptr) {
 169     if(!strcmp(d->d_name, ".") || !strcmp(d->d_name, "..")) {
 170       continue;
 171     }
 172     zoneVersions.push_back(std::stoi(d->d_name));
 173   }
 174   closedir(dp);
 175   g_log<<Logger::Info<<"Found "<<zoneVersions.size()<<" versions of "<<domain<<", asked to keep "<<keep<<", ";
 176   if (zoneVersions.size() <= keep) {
 177     g_log<<Logger::Info<<"not cleaning up"<<endl;
 178     return;
 179   }
 180   g_log<<Logger::Info<<"cleaning up the oldest "<<zoneVersions.size() - keep<<endl;
 181
 182   // Sort the versions
 183   std::sort(zoneVersions.begin(), zoneVersions.end(), sortSOA);
 184
 185   // And delete all the old ones
 186   {
 187     // Lock to ensure no one reads this.
 188     std::lock_guard<std::mutex> guard(g_soas_mutex);
 189     for (auto iter = zoneVersions.cbegin(); iter != zoneVersions.cend() - keep; ++iter) {
 190       string fname = dir + "/" + std::to_string(*iter);
 191       g_log<<Logger::Debug<<"Removing "<<fname<<endl;
 192       unlink(fname.c_str());
 193     }
 194   }
 195 }
 196
 197 static shared_ptr<SOARecordContent> getSOAFromRecords(const records_t& records) {
 198   for (const auto& dnsrecord : records) {
 199     if (dnsrecord.d_type == QType::SOA) {
 200       auto soa = getRR<SOARecordContent>(dnsrecord);
 201       if (soa == nullptr) {
 202         throw PDNSException("Unable to determine SOARecordContent from old records");
 203       }
 204       return soa;
 205     }
 206   }
 207   throw PDNSException("No SOA in supplied records");
 208 }
 209
 210 static void makeIXFRDiff(const records_t& from, const records_t& to, std::shared_ptr<ixfrdiff_t>& diff, const shared_ptr<SOARecordContent>& fromSOA = nullptr, const shared_ptr<SOARecordContent>& toSOA = nullptr) {
 211   set_difference(from.cbegin(), from.cend(), to.cbegin(), to.cend(), back_inserter(diff->removals), from.value_comp());
 212   set_difference(to.cbegin(), to.cend(), from.cbegin(), from.cend(), back_inserter(diff->additions), from.value_comp());
 213   diff->oldSOA = fromSOA;
 214   if (fromSOA == nullptr) {
 215     diff->oldSOA = getSOAFromRecords(from);
 216   }
 217   diff->newSOA = toSOA;
 218   if (toSOA == nullptr) {
 219     diff->newSOA = getSOAFromRecords(to);
 220   }
 221 }
 222
 223 /* you can _never_ alter the content of the resulting shared pointer */
 224 static std::shared_ptr<ixfrinfo_t> getCurrentZoneInfo(const DNSName& domain)
 225 {
 226   std::lock_guard<std::mutex> guard(g_soas_mutex);
 227   return g_soas[domain];
 228 }
 229
 230 static void updateCurrentZoneInfo(const DNSName& domain, std::shared_ptr<ixfrinfo_t>& newInfo)
 231 {
 232   std::lock_guard<std::mutex> guard(g_soas_mutex);
 233   g_soas[domain] = newInfo;
 234 }
 235
 236 void updateThread(const string& workdir, const uint16_t& keep, const uint16_t& axfrTimeout) {
 237   std::map<DNSName, time_t> lastCheck;
 238
 239   // Initialize the serials we have
 240   for (const auto &domainConfig : g_domainConfigs) {
 241     DNSName domain = domainConfig.first;
 242     lastCheck[domain] = 0;
 243     string dir = workdir + "/" + domain.toString();
 244     try {
 245       g_log<<Logger::Info<<"Trying to initially load domain "<<domain<<" from disk"<<endl;
 246       auto serial = getSerialsFromDir(dir);
 247       shared_ptr<SOARecordContent> soa;
 248       {
 249         string fname = workdir + "/" + domain.toString() + "/" + std::to_string(serial);
 250         loadSOAFromDisk(domain, fname, soa);
 251         records_t records;
 252         if (soa != nullptr) {
 253           loadZoneFromDisk(records, fname, domain);
 254         }
 255         auto zoneInfo = std::make_shared<ixfrinfo_t>();
 256         zoneInfo->latestAXFR = std::move(records);
 257         zoneInfo->soa = soa;
 258         updateCurrentZoneInfo(domain, zoneInfo);
 259       }
 260       if (soa != nullptr) {
 261         g_log<<Logger::Notice<<"Loaded zone "<<domain<<" with serial "<<soa->d_st.serial<<endl;
 262         // Initial cleanup
 263         cleanUpDomain(domain, keep, workdir);
 264       }
 265     } catch (runtime_error &e) {
 266       // Most likely, the directory does not exist.
 267       g_log<<Logger::Info<<e.what()<<", attempting to create"<<endl;
 268       // Attempt to create it, if _that_ fails, there is no hope
 269       if (mkdir(dir.c_str(), 0777) == -1 && errno != EEXIST) {
 270         g_log<<Logger::Error<<"Could not create '"<<dir<<"': "<<strerror(errno)<<endl;
 271         exit(EXIT_FAILURE);
 272       }
 273     }
 274   }
 275
 276   g_log<<Logger::Notice<<"Update Thread started"<<endl;
 277
 278   while (true) {
 279     if (g_exiting) {
 280       g_log<<Logger::Notice<<"UpdateThread stopped"<<endl;
 281       break;
 282     }
 283     time_t now = time(nullptr);
 284     for (const auto &domainConfig : g_domainConfigs) {
 285
 286       if (g_exiting) {
 287         break;
 288       }
 289
 290       DNSName domain = domainConfig.first;
 291       shared_ptr<SOARecordContent> current_soa;
 292       const auto& zoneInfo = getCurrentZoneInfo(domain);
 293       if (zoneInfo != nullptr) {
 294         current_soa = zoneInfo->soa;
 295       }
 296
 297       auto& zoneLastCheck = lastCheck[domain];
 298       if ((current_soa != nullptr && now - zoneLastCheck < current_soa->d_st.refresh) || // Only check if we have waited `refresh` seconds
 299           (current_soa == nullptr && now - zoneLastCheck < 30))  {                       // Or if we could not get an update at all still, every 30 seconds
 300         continue;
 301       }
 302
 303       // TODO Keep track of 'down' masters
 304       set<ComboAddress>::const_iterator it(domainConfig.second.masters.begin());
 305       std::advance(it, random() % domainConfig.second.masters.size());
 306       ComboAddress master = *it;
 307
 308       string dir = workdir + "/" + domain.toString();
 309       g_log<<Logger::Info<<"Attempting to retrieve SOA Serial update for '"<<domain<<"' from '"<<master.toStringWithPort()<<"'"<<endl;
 310       shared_ptr<SOARecordContent> sr;
 311       try {
 312         zoneLastCheck = now;
 313         auto newSerial = getSerialFromMaster(master, domain, sr); // TODO TSIG
 314         if(current_soa != nullptr) {
 315           g_log<<Logger::Info<<"Got SOA Serial for "<<domain<<" from "<<master.toStringWithPort()<<": "<< newSerial<<", had Serial: "<<current_soa->d_st.serial;
 316           if (newSerial == current_soa->d_st.serial) {
 317             g_log<<Logger::Info<<", not updating."<<endl;
 318             continue;
 319           }
 320           g_log<<Logger::Info<<", will update."<<endl;
 321         }
 322       } catch (runtime_error &e) {
 323         g_log<<Logger::Warning<<"Unable to get SOA serial update for '"<<domain<<"' from master "<<master.toStringWithPort()<<": "<<e.what()<<endl;
 324         continue;
 325       }
 326       // Now get the full zone!
 327       g_log<<Logger::Info<<"Attempting to receive full zonedata for '"<<domain<<"'"<<endl;
 328       ComboAddress local = master.isIPv4() ? ComboAddress("0.0.0.0") : ComboAddress("::");
 329       TSIGTriplet tt;
 330
 331       // The *new* SOA
 332       shared_ptr<SOARecordContent> soa;
 333       records_t records;
 334       try {
 335         AXFRRetriever axfr(master, domain, tt, &local);
 336         unsigned int nrecords=0;
 337         Resolver::res_t nop;
 338         vector<DNSRecord> chunk;
 339         time_t t_start = time(nullptr);
 340         time_t axfr_now = time(nullptr);
 341         while(axfr.getChunk(nop, &chunk, (axfr_now - t_start + axfrTimeout))) {
 342           for(auto& dr : chunk) {
 343             if(dr.d_type == QType::TSIG)
 344               continue;
 345             dr.d_name.makeUsRelative(domain);
 346             records.insert(dr);
 347             nrecords++;
 348             if (dr.d_type == QType::SOA) {
 349               soa = getRR<SOARecordContent>(dr);
 350             }
 351           }
 352           axfr_now = time(nullptr);
 353           if (axfr_now - t_start > axfrTimeout) {
 354             throw PDNSException("Total AXFR time exceeded!");
 355           }
 356         }
 357         if (soa == nullptr) {
 358           g_log<<Logger::Warning<<"No SOA was found in the AXFR of "<<domain<<endl;
 359           continue;
 360         }
 361         g_log<<Logger::Notice<<"Retrieved all zone data for "<<domain<<". Received "<<nrecords<<" records."<<endl;
 362       } catch (PDNSException &e) {
 363         g_log<<Logger::Warning<<"Could not retrieve AXFR for '"<<domain<<"': "<<e.reason<<endl;
 364         continue;
 365       } catch (runtime_error &e) {
 366         g_log<<Logger::Warning<<"Could not retrieve AXFR for zone '"<<domain<<"': "<<e.what()<<endl;
 367         continue;
 368       }
 369
 370       try {
 371
 372         writeZoneToDisk(records, domain, dir);
 373         g_log<<Logger::Notice<<"Wrote zonedata for "<<domain<<" with serial "<<soa->d_st.serial<<" to "<<dir<<endl;
 374
 375         const auto oldZoneInfo = getCurrentZoneInfo(domain);
 376         auto zoneInfo = std::make_shared<ixfrinfo_t>();
 377
 378         if (oldZoneInfo && !oldZoneInfo->latestAXFR.empty()) {
 379           auto diff = std::make_shared<ixfrdiff_t>();
 380           zoneInfo->ixfrDiffs = oldZoneInfo->ixfrDiffs;
 381           g_log<<Logger::Debug<<"Calculating diff for "<<domain<<endl;
 382           makeIXFRDiff(oldZoneInfo->latestAXFR, records, diff, oldZoneInfo->soa, soa);
 383           g_log<<Logger::Debug<<"Calculated diff for "<<domain<<", we had "<<diff->removals.size()<<" removals and "<<diff->additions.size()<<" additions"<<endl;
 384           zoneInfo->ixfrDiffs.push_back(std::move(diff));
 385         }
 386
 387         // Clean up the diffs
 388         while (zoneInfo->ixfrDiffs.size() > keep) {
 389           zoneInfo->ixfrDiffs.erase(zoneInfo->ixfrDiffs.begin());
 390         }
 391
 392         g_log<<Logger::Debug<<"Zone "<<domain<<" previously contained "<<(oldZoneInfo ? oldZoneInfo->latestAXFR.size() : 0)<<" entries, "<<records.size()<<" now"<<endl;
 393         zoneInfo->latestAXFR = std::move(records);
 394         zoneInfo->soa = soa;
 395         updateCurrentZoneInfo(domain, zoneInfo);
 396       } catch (PDNSException &e) {
 397         g_log<<Logger::Warning<<"Could not save zone '"<<domain<<"' to disk: "<<e.reason<<endl;
 398       } catch (runtime_error &e) {
 399         g_log<<Logger::Warning<<"Could not save zone '"<<domain<<"' to disk: "<<e.what()<<endl;
 400       }
 401
 402       // Now clean up the directory
 403       cleanUpDomain(domain, keep, workdir);
 404     } /* for (const auto &domain : domains) */
 405     sleep(1);
 406   } /* while (true) */
 407 } /* updateThread */
 408
 409 static bool checkQuery(const MOADNSParser& mdp, const ComboAddress& saddr, const bool udp = true, const string& logPrefix="") {
 410   vector<string> info_msg;
 411
 412   g_log<<Logger::Debug<<logPrefix<<"Had "<<mdp.d_qname<<"|"<<QType(mdp.d_qtype).getName()<<" query from "<<saddr.toStringWithPort()<<endl;
 413
 414   if (udp && mdp.d_qtype != QType::SOA && mdp.d_qtype != QType::IXFR) {
 415     info_msg.push_back("QType is unsupported (" + QType(mdp.d_qtype).getName() + " is not in {SOA,IXFR}");
 416   }
 417
 418   if (!udp && mdp.d_qtype != QType::SOA && mdp.d_qtype != QType::IXFR && mdp.d_qtype != QType::AXFR) {
 419     info_msg.push_back("QType is unsupported (" + QType(mdp.d_qtype).getName() + " is not in {SOA,IXFR,AXFR}");
 420   }
 421
 422   {
 423     if (g_domainConfigs.find(mdp.d_qname) == g_domainConfigs.end()) {
 424       info_msg.push_back("Domain name '" + mdp.d_qname.toLogString() + "' is not configured for distribution");
 425     }
 426
 427     const auto zoneInfo = getCurrentZoneInfo(mdp.d_qname);
 428     if (zoneInfo == nullptr) {
 429       info_msg.push_back("Domain has not been transferred yet");
 430     }
 431   }
 432
 433   if (!info_msg.empty()) {
 434     g_log<<Logger::Warning<<logPrefix<<"Ignoring "<<mdp.d_qname<<"|"<<QType(mdp.d_qtype).getName()<<" query from "<<saddr.toStringWithPort();
 435     g_log<<Logger::Warning<<": ";
 436     bool first = true;
 437     for (const auto& s : info_msg) {
 438       if (!first) {
 439         g_log<<Logger::Warning<<", ";
 440         first = false;
 441       }
 442       g_log<<Logger::Warning<<s;
 443     }
 444     g_log<<Logger::Warning<<endl;
 445     return false;
 446   }
 447
 448   return true;
 449 }
 450
 451 /*
 452  * Returns a vector<uint8_t> that represents the full response to a SOA
 453  * query. QNAME is read from mdp.
 454  */
 455 static bool makeSOAPacket(const MOADNSParser& mdp, vector<uint8_t>& packet) {
 456
 457   auto zoneInfo = getCurrentZoneInfo(mdp.d_qname);
 458   if (zoneInfo == nullptr) {
 459     return false;
 460   }
 461
 462   DNSPacketWriter pw(packet, mdp.d_qname, mdp.d_qtype);
 463   pw.getHeader()->id = mdp.d_header.id;
 464   pw.getHeader()->rd = mdp.d_header.rd;
 465   pw.getHeader()->qr = 1;
 466
 467   pw.startRecord(mdp.d_qname, QType::SOA);
 468   zoneInfo->soa->toPacket(pw);
 469   pw.commit();
 470
 471   return true;
 472 }
 473
 474 static vector<uint8_t> getSOAPacket(const MOADNSParser& mdp, const shared_ptr<SOARecordContent>& soa) {
 475   vector<uint8_t> packet;
 476   DNSPacketWriter pw(packet, mdp.d_qname, mdp.d_qtype);
 477   pw.getHeader()->id = mdp.d_header.id;
 478   pw.getHeader()->rd = mdp.d_header.rd;
 479   pw.getHeader()->qr = 1;
 480
 481   // Add the first SOA
 482   pw.startRecord(mdp.d_qname, QType::SOA);
 483   soa->toPacket(pw);
 484   pw.commit();
 485   return packet;
 486 }
 487
 488 static bool sendPacketOverTCP(int fd, const std::vector<uint8_t>& packet)
 489 {
 490   char sendBuf[2];
 491   sendBuf[0]=packet.size()/256;
 492   sendBuf[1]=packet.size()%256;
 493
 494   ssize_t send = writen2(fd, sendBuf, 2);
 495   send += writen2(fd, &packet[0], packet.size());
 496   return true;
 497 }
 498
 499 static bool addRecordToWriter(DNSPacketWriter& pw, const DNSName& zoneName, const DNSRecord& record, bool compress)
 500 {
 501   pw.startRecord(record.d_name + zoneName, record.d_type, record.d_ttl, QClass::IN, DNSResourceRecord::ANSWER, compress);
 502   record.d_content->toPacket(pw);
 503   if (pw.size() > 65535) {
 504     pw.rollback();
 505     return false;
 506   }
 507   return true;
 508 }
 509
 510 template <typename T> static bool sendRecordsOverTCP(int fd, const MOADNSParser& mdp, const T& records)
 511 {
 512   vector<uint8_t> packet;
 513
 514   for (auto it = records.cbegin(); it != records.cend();) {
 515     bool recordsAdded = false;
 516     packet.clear();
 517     DNSPacketWriter pw(packet, mdp.d_qname, mdp.d_qtype);
 518     pw.getHeader()->id = mdp.d_header.id;
 519     pw.getHeader()->rd = mdp.d_header.rd;
 520     pw.getHeader()->qr = 1;
 521
 522     while (it != records.cend()) {
 523       if (it->d_type == QType::SOA) {
 524         it++;
 525         continue;
 526       }
 527
 528       if (addRecordToWriter(pw, mdp.d_qname, *it, g_compress)) {
 529         recordsAdded = true;
 530         it++;
 531       }
 532       else {
 533         if (recordsAdded) {
 534           pw.commit();
 535           sendPacketOverTCP(fd, packet);
 536         }
 537         if (it == records.cbegin()) {
 538           /* something is wrong */
 539           return false;
 540         }
 541
 542         break;
 543       }
 544     }
 545
 546     if (it == records.cend() && recordsAdded) {
 547       pw.commit();
 548       sendPacketOverTCP(fd, packet);
 549     }
 550   }
 551
 552   return true;
 553 }
 554
 555
 556 static bool handleAXFR(int fd, const MOADNSParser& mdp) {
 557   /* we get a shared pointer of the zone info that we can't modify, ever.
 558      A newer one may arise in the meantime, but this one will stay valid
 559      until we release it.
 560   */
 561   auto zoneInfo = getCurrentZoneInfo(mdp.d_qname);
 562   if (zoneInfo == nullptr) {
 563     return false;
 564   }
 565
 566   shared_ptr<SOARecordContent> soa = zoneInfo->soa;
 567   const records_t& records = zoneInfo->latestAXFR;
 568
 569   // Initial SOA
 570   const auto soaPacket = getSOAPacket(mdp, soa);
 571   if (!sendPacketOverTCP(fd, soaPacket)) {
 572     return false;
 573   }
 574
 575   if (!sendRecordsOverTCP(fd, mdp, records)) {
 576     return false;
 577   }
 578
 579   // Final SOA
 580   if (!sendPacketOverTCP(fd, soaPacket)) {
 581     return false;
 582   }
 583
 584   return true;
 585 }
 586
 587 /* Produces an IXFR if one can be made according to the rules in RFC 1995 and
 588  * creates a SOA or AXFR packet when required by the RFC.
 589  */
 590 static bool handleIXFR(int fd, const ComboAddress& destination, const MOADNSParser& mdp, const shared_ptr<SOARecordContent>& clientSOA) {
 591   vector<std::shared_ptr<ixfrdiff_t>> toSend;
 592
 593   /* we get a shared pointer of the zone info that we can't modify, ever.
 594      A newer one may arise in the meantime, but this one will stay valid
 595      until we release it.
 596   */
 597   auto zoneInfo = getCurrentZoneInfo(mdp.d_qname);
 598   if (zoneInfo == nullptr) {
 599     return false;
 600   }
 601
 602   uint32_t ourLatestSerial = zoneInfo->soa->d_st.serial;
 603
 604   if (rfc1982LessThan(ourLatestSerial, clientSOA->d_st.serial) || ourLatestSerial == clientSOA->d_st.serial) {
 605     /* RFC 1995 Section 2
 606      *    If an IXFR query with the same or newer version number than that of
 607      *    the server is received, it is replied to with a single SOA record of
 608      *    the server's current version, just as in AXFR.
 609      */
 610     vector<uint8_t> packet;
 611     bool ret = makeSOAPacket(mdp, packet);
 612     if (ret) {
 613       sendPacketOverTCP(fd, packet);
 614     }
 615     return ret;
 616   }
 617
 618   // as we use push_back in the updater, we know the vector is sorted as oldest first
 619   bool shouldAdd = false;
 620   // Get all relevant IXFR differences
 621   for (const auto& diff : zoneInfo->ixfrDiffs) {
 622     if (shouldAdd) {
 623       toSend.push_back(diff);
 624       continue;
 625     }
 626     if (diff->oldSOA->d_st.serial == clientSOA->d_st.serial) {
 627       toSend.push_back(diff);
 628       // Add all consecutive diffs
 629       shouldAdd = true;
 630     }
 631   }
 632
 633   if (toSend.empty()) {
 634     g_log<<Logger::Warning<<"No IXFR available from serial "<<clientSOA->d_st.serial<<" for zone "<<mdp.d_qname<<", attempting to send AXFR"<<endl;
 635     return handleAXFR(fd, mdp);
 636   }
 637
 638   std::vector<std::vector<uint8_t>> packets;
 639   for (const auto& diff : toSend) {
 640     /* An IXFR packet's ANSWER section looks as follows:
 641      * SOA new_serial
 642      * SOA old_serial
 643      * ... removed records ...
 644      * SOA new_serial
 645      * ... added records ...
 646      * SOA new_serial
 647      */
 648
 649     const auto newSOAPacket = getSOAPacket(mdp, diff->newSOA);
 650     const auto oldSOAPacket = getSOAPacket(mdp, diff->oldSOA);
 651
 652     if (!sendPacketOverTCP(fd, newSOAPacket)) {
 653       return false;
 654     }
 655
 656     if (!sendPacketOverTCP(fd, oldSOAPacket)) {
 657       return false;
 658     }
 659
 660     if (!sendRecordsOverTCP(fd, mdp, diff->removals)) {
 661       return false;
 662     }
 663
 664     if (!sendPacketOverTCP(fd, newSOAPacket)) {
 665       return false;
 666     }
 667
 668     if (!sendRecordsOverTCP(fd, mdp, diff->additions)) {
 669       return false;
 670     }
 671
 672     if (!sendPacketOverTCP(fd, newSOAPacket)) {
 673       return false;
 674     }
 675   }
 676
 677   return true;
 678 }
 679
 680 static bool allowedByACL(const ComboAddress& addr) {
 681   return g_acl.match(addr);
 682 }
 683
 684 static void handleUDPRequest(int fd, boost::any&) {
 685   // TODO make the buffer-size configurable
 686   char buf[4096];
 687   ComboAddress saddr;
 688   socklen_t fromlen = sizeof(saddr);
 689   int res = recvfrom(fd, buf, sizeof(buf), 0, (struct sockaddr*) &saddr, &fromlen);
 690
 691   if (res == 0) {
 692     g_log<<Logger::Warning<<"Got an empty message from "<<saddr.toStringWithPort()<<endl;
 693     return;
 694   }
 695
 696   if(res < 0) {
 697     auto savedErrno = errno;
 698     g_log<<Logger::Warning<<"Could not read message from "<<saddr.toStringWithPort()<<": "<<strerror(savedErrno)<<endl;
 699     return;
 700   }
 701
 702   if (saddr == ComboAddress("0.0.0.0", 0)) {
 703     g_log<<Logger::Warning<<"Could not determine source of message"<<endl;
 704     return;
 705   }
 706
 707   if (!allowedByACL(saddr)) {
 708     g_log<<Logger::Warning<<"UDP query from "<<saddr.toString()<<" is not allowed, dropping"<<endl;
 709     return;
 710   }
 711
 712   MOADNSParser mdp(true, string(buf, res));
 713   if (!checkQuery(mdp, saddr)) {
 714     return;
 715   }
 716
 717   /* RFC 1995 Section 2
 718    *    Transport of a query may be by either UDP or TCP.  If an IXFR query
 719    *    is via UDP, the IXFR server may attempt to reply using UDP if the
 720    *    entire response can be contained in a single DNS packet.  If the UDP
 721    *    reply does not fit, the query is responded to with a single SOA
 722    *    record of the server's current version to inform the client that a
 723    *    TCP query should be initiated.
 724    *
 725    * Let's not complicate this with IXFR over UDP (and looking if we need to truncate etc).
 726    * Just send the current SOA and let the client try over TCP
 727    */
 728   vector<uint8_t> packet;
 729   makeSOAPacket(mdp, packet);
 730   if(sendto(fd, &packet[0], packet.size(), 0, (struct sockaddr*) &saddr, fromlen) < 0) {
 731     auto savedErrno = errno;
 732     g_log<<Logger::Warning<<"Could not send reply for "<<mdp.d_qname<<"|"<<QType(mdp.d_qtype).getName()<<" to "<<saddr.toStringWithPort()<<": "<<strerror(savedErrno)<<endl;
 733   }
 734   return;
 735 }
 736
 737 static void handleTCPRequest(int fd, boost::any&) {
 738   ComboAddress saddr;
 739   int cfd = 0;
 740
 741   try {
 742     cfd = SAccept(fd, saddr);
 743     setBlocking(cfd);
 744   } catch(runtime_error &e) {
 745     g_log<<Logger::Error<<e.what()<<endl;
 746     return;
 747   }
 748
 749   if (saddr == ComboAddress("0.0.0.0", 0)) {
 750     g_log<<Logger::Warning<<"Could not determine source of message"<<endl;
 751     close(cfd);
 752     return;
 753   }
 754
 755   if (!allowedByACL(saddr)) {
 756     g_log<<Logger::Warning<<"TCP query from "<<saddr.toString()<<" is not allowed, dropping"<<endl;
 757     close(cfd);
 758     return;
 759   }
 760
 761   {
 762     std::lock_guard<std::mutex> lg(g_tcpRequestFDsMutex);
 763     g_tcpRequestFDs.push({cfd, saddr});
 764   }
 765   g_tcpHandlerCV.notify_one();
 766 }
 767
 768 /* Thread to handle TCP traffic
 769  */
 770 static void tcpWorker(int tid) {
 771   string prefix = "TCP Worker " + std::to_string(tid) + ": ";
 772
 773   while(true) {
 774     g_log<<Logger::Debug<<prefix<<"ready for a new request!"<<endl;
 775     std::unique_lock<std::mutex> lk(g_tcpRequestFDsMutex);
 776     g_tcpHandlerCV.wait(lk, []{return g_tcpRequestFDs.size() || g_exiting ;});
 777     if (g_exiting) {
 778       g_log<<Logger::Debug<<prefix<<"Stopping thread"<<endl;
 779       break;
 780     }
 781     g_log<<Logger::Debug<<prefix<<"Going to handle a query"<<endl;
 782     auto request = g_tcpRequestFDs.front();
 783     g_tcpRequestFDs.pop();
 784     lk.unlock();
 785
 786     int cfd = request.first;
 787     ComboAddress saddr = request.second;
 788
 789     char buf[4096];
 790     ssize_t res;
 791     try {
 792       uint16_t toRead;
 793       readn2(cfd, &toRead, sizeof(toRead));
 794       toRead = std::min(ntohs(toRead), static_cast<uint16_t>(sizeof(buf)));
 795       res = readn2WithTimeout(cfd, &buf, toRead, 2);
 796       g_log<<Logger::Debug<<prefix<<"Had message of "<<std::to_string(toRead)<<" bytes from "<<saddr.toStringWithPort()<<endl;
 797     } catch (runtime_error &e) {
 798       g_log<<Logger::Warning<<prefix<<"Could not read message from "<<saddr.toStringWithPort()<<": "<<e.what()<<endl;
 799       close(cfd);
 800       continue;
 801     }
 802
 803     try {
 804       MOADNSParser mdp(true, string(buf, res));
 805
 806       if (!checkQuery(mdp, saddr, false, prefix)) {
 807         close(cfd);
 808         continue;
 809       }
 810
 811       if (mdp.d_qtype == QType::SOA) {
 812         vector<uint8_t> packet;
 813         bool ret = makeSOAPacket(mdp, packet);
 814         if (!ret) {
 815           close(cfd);
 816           continue;
 817         }
 818         sendPacketOverTCP(cfd, packet);
 819       }
 820       else if (mdp.d_qtype == QType::AXFR) {
 821         if (!handleAXFR(cfd, mdp)) {
 822           close(cfd);
 823           continue;
 824         }
 825       }
 826       else if (mdp.d_qtype == QType::IXFR) {
 827         /* RFC 1995 section 3:
 828          *  The IXFR query packet format is the same as that of a normal DNS
 829          *  query, but with the query type being IXFR and the authority section
 830          *  containing the SOA record of client's version of the zone.
 831          */
 832         shared_ptr<SOARecordContent> clientSOA;
 833         for (auto &answer : mdp.d_answers) {
 834           // from dnsparser.hh:
 835           // typedef vector<pair<DNSRecord, uint16_t > > answers_t;
 836           if (answer.first.d_type == QType::SOA && answer.first.d_place == DNSResourceRecord::AUTHORITY) {
 837             clientSOA = getRR<SOARecordContent>(answer.first);
 838             if (clientSOA != nullptr) {
 839               break;
 840             }
 841           }
 842         } /* for (auto const &answer : mdp.d_answers) */
 843
 844         if (clientSOA == nullptr) {
 845           g_log<<Logger::Warning<<prefix<<"IXFR request packet did not contain a SOA record in the AUTHORITY section"<<endl;
 846           close(cfd);
 847           continue;
 848         }
 849
 850         if (!handleIXFR(cfd, saddr, mdp, clientSOA)) {
 851           close(cfd);
 852           continue;
 853         }
 854       } /* if (mdp.d_qtype == QType::IXFR) */
 855
 856       shutdown(cfd, 2);
 857     } catch (MOADNSException &e) {
 858       g_log<<Logger::Warning<<prefix<<"Could not parse DNS packet from "<<saddr.toStringWithPort()<<": "<<e.what()<<endl;
 859     } catch (runtime_error &e) {
 860       g_log<<Logger::Warning<<prefix<<"Could not write reply to "<<saddr.toStringWithPort()<<": "<<e.what()<<endl;
 861     }
 862     // bye!
 863     close(cfd);
 864
 865     if (g_exiting) {
 866       break;
 867     }
 868   }
 869 }
 870
 871 /* Parses the configuration file in configpath into config, adding defaults for
 872  * missing parameters (if applicable), returning true if the config file was
 873  * good, false otherwise. Will log all issues with the config
 874  */
 875 static bool parseAndCheckConfig(const string& configpath, YAML::Node& config) {
 876   g_log<<Logger::Info<<"Loading configuration file from "<<configpath<<endl;
 877   try {
 878     config = YAML::LoadFile(configpath);
 879   } catch (const runtime_error &e) {
 880     g_log<<Logger::Error<<"Unable to load configuration file '"<<configpath<<"': "<<e.what()<<endl;
 881     return false;
 882   }
 883
 884   bool retval = true;
 885
 886   if (config["keep"]) {
 887     try {
 888       config["keep"].as<uint16_t>();
 889     } catch (const runtime_error &e) {
 890       g_log<<Logger::Error<<"Unable to read 'keep' value: "<<e.what()<<endl;
 891       retval = false;
 892     }
 893   } else {
 894     config["keep"] = 20;
 895   }
 896
 897   if (config["axfr-timeout"]) {
 898     try {
 899       config["axfr-timeout"].as<uint16_t>();
 900     } catch (const runtime_error &e) {
 901       g_log<<Logger::Error<<"Unable to read 'axfr-timeout' value: "<<e.what()<<endl;
 902     }
 903   } else {
 904     config["axfr-timeout"] = 20;
 905   }
 906
 907   if (config["tcp-in-threads"]) {
 908     try {
 909       config["tcp-in-threads"].as<uint16_t>();
 910     } catch (const runtime_error &e) {
 911       g_log<<Logger::Error<<"Unable to read 'tcp-in-threads' value: "<<e.what()<<endl;
 912     }
 913   } else {
 914     config["tcp-in-threads"] = 10;
 915   }
 916
 917   if (config["listen"]) {
 918     try {
 919       config["listen"].as<vector<ComboAddress>>();
 920     } catch (const runtime_error &e) {
 921       g_log<<Logger::Error<<"Unable to read 'listen' value: "<<e.what()<<endl;
 922       retval = false;
 923     }
 924   } else {
 925     config["listen"].push_back("127.0.0.1:53");
 926     config["listen"].push_back("[::1]:53");
 927   }
 928
 929   if (config["acl"]) {
 930     try {
 931       config["acl"].as<vector<string>>();
 932     } catch (const runtime_error &e) {
 933       g_log<<Logger::Error<<"Unable to read 'acl' value: "<<e.what()<<endl;
 934       retval = false;
 935     }
 936   } else {
 937     config["acl"].push_back("127.0.0.0/8");
 938     config["acl"].push_back("::1/128");
 939   }
 940
 941   if (config["work-dir"]) {
 942     try {
 943       config["work-dir"].as<string>();
 944     } catch(const runtime_error &e) {
 945       g_log<<Logger::Error<<"Unable to read 'work-dir' value: "<<e.what()<<endl;
 946       retval = false;
 947     }
 948   } else {
 949     char tmp[512];
 950     config["work-dir"] = getcwd(tmp, sizeof(tmp)) ? string(tmp) : "";;
 951   }
 952
 953   if (config["uid"]) {
 954     try {
 955       config["uid"].as<string>();
 956     } catch(const runtime_error &e) {
 957       g_log<<Logger::Error<<"Unable to read 'uid' value: "<<e.what()<<endl;
 958       retval = false;
 959     }
 960   }
 961
 962   if (config["gid"]) {
 963     try {
 964       config["gid"].as<string>();
 965     } catch(const runtime_error &e) {
 966       g_log<<Logger::Error<<"Unable to read 'gid' value: "<<e.what()<<endl;
 967       retval = false;
 968     }
 969   }
 970
 971   if (config["domains"]) {
 972     if (config["domains"].size() == 0) {
 973       g_log<<Logger::Error<<"No domains configured"<<endl;
 974       retval = false;
 975     }
 976     for (auto const &domain : config["domains"]) {
 977       try {
 978         if (!domain["domain"]) {
 979           g_log<<Logger::Error<<"An entry in 'domains' is missing a 'domain' key!"<<endl;
 980           retval = false;
 981           continue;
 982         }
 983         domain["domain"].as<DNSName>();
 984       } catch (const runtime_error &e) {
 985         g_log<<Logger::Error<<"Unable to read domain '"<<domain["domain"].as<string>()<<"': "<<e.what()<<endl;
 986       }
 987       try {
 988         if (!domain["master"]) {
 989           g_log<<Logger::Error<<"Domain '"<<domain["domain"].as<string>()<<"' has no master configured!"<<endl;
 990           retval = false;
 991           continue;
 992         }
 993         domain["master"].as<ComboAddress>();
 994       } catch (const runtime_error &e) {
 995         g_log<<Logger::Error<<"Unable to read domain '"<<domain["domain"].as<string>()<<"' master address: "<<e.what()<<endl;
 996         retval = false;
 997       }
 998     }
 999   } else {
1000     g_log<<Logger::Error<<"No domains configured"<<endl;
1001     retval = false;
1002   }
1003
1004   if (config["compress"]) {
1005     try {
1006       config["compress"].as<bool>();
1007     }
1008     catch (const runtime_error &e) {
1009       g_log<<Logger::Error<<"Unable to read 'compress' value: "<<e.what()<<endl;
1010       retval = false;
1011     }
1012   }
1013   else {
1014     config["compress"] = false;
1015   }
1016
1017   return retval;
1018 }
1019
1020 int main(int argc, char** argv) {
1021   g_log.setLoglevel(Logger::Notice);
1022   g_log.toConsole(Logger::Notice);
1023   g_log.setPrefixed(true);
1024   g_log.disableSyslog(true);
1025   g_log.setTimestamps(false);
1026   po::variables_map g_vm;
1027   try {
1028     po::options_description desc("IXFR distribution tool");
1029     desc.add_options()
1030       ("help", "produce help message")
1031       ("version", "Display the version of ixfrdist")
1032       ("verbose", "Be verbose")
1033       ("debug", "Be even more verbose")
1034       ("config", po::value<string>()->default_value(SYSCONFDIR + string("/ixfrdist.yml")), "Configuration file to use")
1035       ;
1036
1037     po::store(po::command_line_parser(argc, argv).options(desc).run(), g_vm);
1038     po::notify(g_vm);
1039
1040     if (g_vm.count("help") > 0) {
1041       usage(desc);
1042       return EXIT_SUCCESS;
1043     }
1044
1045     if (g_vm.count("version") > 0) {
1046       cout<<"ixfrdist "<<VERSION<<endl;
1047       return EXIT_SUCCESS;
1048     }
1049   } catch (po::error &e) {
1050     g_log<<Logger::Error<<e.what()<<". See `ixfrdist --help` for valid options"<<endl;
1051     return(EXIT_FAILURE);
1052   }
1053
1054   bool had_error = false;
1055
1056   if (g_vm.count("verbose")) {
1057     g_log.setLoglevel(Logger::Info);
1058     g_log.toConsole(Logger::Info);
1059   }
1060
1061   if (g_vm.count("debug") > 0) {
1062     g_log.setLoglevel(Logger::Debug);
1063     g_log.toConsole(Logger::Debug);
1064   }
1065
1066   g_log<<Logger::Notice<<"IXFR distributor version "<<VERSION<<" starting up!"<<endl;
1067
1068   YAML::Node config;
1069   if (!parseAndCheckConfig(g_vm["config"].as<string>(), config)) {
1070     // parseAndCheckConfig already logged whatever was wrong
1071     return EXIT_FAILURE;
1072   }
1073
1074   /*  From hereon out, we known that all the values in config are valid. */
1075
1076   for (auto const &domain : config["domains"]) {
1077     set<ComboAddress> s;
1078     s.insert(domain["master"].as<ComboAddress>());
1079     g_domainConfigs[domain["domain"].as<DNSName>()].masters = s;
1080   }
1081
1082   for (const auto &addr : config["acl"].as<vector<string>>()) {
1083     try {
1084       g_acl.addMask(addr);
1085     } catch (const NetmaskException &e) {
1086       g_log<<Logger::Error<<e.reason<<endl;
1087       had_error = true;
1088     }
1089   }
1090   g_log<<Logger::Notice<<"ACL set to "<<g_acl.toString()<<"."<<endl;
1091
1092   if (config["compress"]) {
1093     g_compress = config["compress"].as<bool>();
1094     if (g_compress) {
1095       g_log<<Logger::Notice<<"Record compression is enabled."<<endl;
1096     }
1097   }
1098
1099   FDMultiplexer* fdm = FDMultiplexer::getMultiplexerSilent();
1100   if (fdm == nullptr) {
1101     g_log<<Logger::Error<<"Could not enable a multiplexer for the listen sockets!"<<endl;
1102     return EXIT_FAILURE;
1103   }
1104
1105   set<int> allSockets;
1106   for (const auto& addr : config["listen"].as<vector<ComboAddress>>()) {
1107     for (const auto& stype : {SOCK_DGRAM, SOCK_STREAM}) {
1108       try {
1109         int s = SSocket(addr.sin4.sin_family, stype, 0);
1110         setNonBlocking(s);
1111         setReuseAddr(s);
1112         SBind(s, addr);
1113         if (stype == SOCK_STREAM) {
1114           SListen(s, 30); // TODO make this configurable
1115         }
1116         fdm->addReadFD(s, stype == SOCK_DGRAM ? handleUDPRequest : handleTCPRequest);
1117         allSockets.insert(s);
1118       } catch(runtime_error &e) {
1119         g_log<<Logger::Error<<e.what()<<endl;
1120         had_error = true;
1121         continue;
1122       }
1123     }
1124   }
1125
1126   int newgid = 0;
1127
1128   if (config["gid"]) {
1129     string gid = config["gid"].as<string>();
1130     if (!(newgid = atoi(gid.c_str()))) {
1131       struct group *gr = getgrnam(gid.c_str());
1132       if (gr == nullptr) {
1133         g_log<<Logger::Error<<"Can not determine group-id for gid "<<gid<<endl;
1134         had_error = true;
1135       } else {
1136         newgid = gr->gr_gid;
1137       }
1138     }
1139     g_log<<Logger::Notice<<"Dropping effective group-id to "<<newgid<<endl;
1140     if (setgid(newgid) < 0) {
1141       g_log<<Logger::Error<<"Could not set group id to "<<newgid<<": "<<stringerror()<<endl;
1142       had_error = true;
1143     }
1144   }
1145
1146   int newuid = 0;
1147
1148   if (config["uid"]) {
1149     string uid = config["uid"].as<string>();
1150     if (!(newuid = atoi(uid.c_str()))) {
1151       struct passwd *pw = getpwnam(uid.c_str());
1152       if (pw == nullptr) {
1153         g_log<<Logger::Error<<"Can not determine user-id for uid "<<uid<<endl;
1154         had_error = true;
1155       } else {
1156         newuid = pw->pw_uid;
1157       }
1158     }
1159
1160     struct passwd *pw = getpwuid(newuid);
1161     if (pw == nullptr) {
1162       if (setgroups(0, nullptr) < 0) {
1163         g_log<<Logger::Error<<"Unable to drop supplementary gids: "<<stringerror()<<endl;
1164         had_error = true;
1165       }
1166     } else {
1167       if (initgroups(pw->pw_name, newgid) < 0) {
1168         g_log<<Logger::Error<<"Unable to set supplementary groups: "<<stringerror()<<endl;
1169         had_error = true;
1170       }
1171     }
1172
1173     g_log<<Logger::Notice<<"Dropping effective user-id to "<<newuid<<endl;
1174     if (setuid(newuid) < 0) {
1175       g_log<<Logger::Error<<"Could not set user id to "<<newuid<<": "<<stringerror()<<endl;
1176       had_error = true;
1177     }
1178   }
1179
1180   if (had_error) {
1181     // We have already sent the errors to stderr, just die
1182     return EXIT_FAILURE;
1183   }
1184
1185   // It all starts here
1186   signal(SIGTERM, handleSignal);
1187   signal(SIGINT, handleSignal);
1188   signal(SIGPIPE, SIG_IGN);
1189
1190   // Init the things we need
1191   reportAllTypes();
1192
1193   dns_random_init();
1194
1195   std::thread ut(updateThread,
1196       config["work-dir"].as<string>(),
1197       config["keep"].as<uint16_t>(),
1198       config["axfr-timeout"].as<uint16_t>());
1199
1200   vector<std::thread> tcpHandlers;
1201   tcpHandlers.reserve(config["tcp-in-threads"].as<uint16_t>());
1202   for (size_t i = 0; i < tcpHandlers.capacity(); ++i) {
1203     tcpHandlers.push_back(std::thread(tcpWorker, i));
1204   }
1205
1206   struct timeval now;
1207   for(;;) {
1208     gettimeofday(&now, 0);
1209     fdm->run(&now);
1210     if (g_exiting) {
1211       g_log<<Logger::Debug<<"Closing listening sockets"<<endl;
1212       for (const int& fd : allSockets) {
1213         try {
1214           closesocket(fd);
1215         } catch(PDNSException &e) {
1216           g_log<<Logger::Error<<e.reason<<endl;
1217         }
1218       }
1219       break;
1220     }
1221   }
1222   g_log<<Logger::Debug<<"Waiting for al threads to stop"<<endl;
1223   g_tcpHandlerCV.notify_all();
1224   ut.join();
1225   for (auto &t : tcpHandlers) {
1226     t.join();
1227   }
1228   g_log<<Logger::Notice<<"IXFR distributor stopped"<<endl;
1229   return EXIT_SUCCESS;
1230 }