2 * This file is part of PowerDNS or dnsdist.
3 * Copyright -- PowerDNS.COM B.V. and its contributors
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.
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.
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.
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.
25 #include <boost/program_options.hpp>
26 #include <arpa/inet.h>
27 #include <sys/types.h>
35 #include <condition_variable>
37 #include "ixfrutils.hh"
38 #include "resolver.hh"
39 #include "dns_random.hh"
45 #include <yaml-cpp/yaml.h>
47 /* BEGIN Needed because of deeper dependencies */
48 #include "arguments.hh"
54 static ArgvMap theArg
;
57 /* END Needed because of deeper dependencies */
59 // Allows reading/writing ComboAddresses and DNSNames in YAML-cpp
62 struct convert
<ComboAddress
> {
63 static Node
encode(const ComboAddress
& rhs
) {
64 return Node(rhs
.toStringWithPort());
66 static bool decode(const Node
& node
, ComboAddress
& rhs
) {
67 if (!node
.IsScalar()) {
71 rhs
= ComboAddress(node
.as
<string
>(), 53);
73 } catch(const runtime_error
&e
) {
75 } catch (const PDNSException
&e
) {
82 struct convert
<DNSName
> {
83 static Node
encode(const DNSName
& rhs
) {
84 return Node(rhs
.toStringRootDot());
86 static bool decode(const Node
& node
, DNSName
& rhs
) {
87 if (!node
.IsScalar()) {
91 rhs
= DNSName(node
.as
<string
>());
93 } catch(const runtime_error
&e
) {
95 } catch (const PDNSException
&e
) {
103 shared_ptr
<SOARecordContent
> oldSOA
;
104 shared_ptr
<SOARecordContent
> newSOA
;
105 vector
<DNSRecord
> removals
;
106 vector
<DNSRecord
> additions
;
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
;
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
120 // This contains the configuration for each domain
121 map
<DNSName
, ixfrdistdomain_t
> g_domainConfigs
;
123 // Map domains and their data
124 std::map
<DNSName
, std::shared_ptr
<ixfrinfo_t
>> g_soas
;
125 std::mutex g_soas_mutex
;
127 // Condition variable for TCP handling
128 std::condition_variable g_tcpHandlerCV
;
129 std::queue
<pair
<int, ComboAddress
>> g_tcpRequestFDs
;
130 std::mutex g_tcpRequestFDsMutex
;
132 namespace po
= boost::program_options
;
134 bool g_exiting
= false;
138 void handleSignal(int signum
) {
139 g_log
<<Logger::Notice
<<"Got "<<strsignal(signum
)<<" signal";
141 g_log
<<Logger::Notice
<<", this is the second time we were asked to stop, forcefully exiting"<<endl
;
144 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
;
148 void usage(po::options_description
&desc
) {
149 cerr
<< "Usage: ixfrdist [OPTION]..."<<endl
;
150 cerr
<< desc
<< "\n";
153 // The compiler does not like using rfc1982LessThan in std::sort directly
154 bool sortSOA(uint32_t i
, uint32_t j
) {
155 return rfc1982LessThan(i
, j
);
158 void cleanUpDomain(const DNSName
& domain
, const uint16_t& keep
, const string
& workdir
) {
159 string dir
= workdir
+ "/" + domain
.toString();
161 dp
= opendir(dir
.c_str());
165 vector
<uint32_t> zoneVersions
;
167 while ((d
= readdir(dp
)) != nullptr) {
168 if(!strcmp(d
->d_name
, ".") || !strcmp(d
->d_name
, "..")) {
171 zoneVersions
.push_back(std::stoi(d
->d_name
));
174 g_log
<<Logger::Info
<<"Found "<<zoneVersions
.size()<<" versions of "<<domain
<<", asked to keep "<<keep
<<", ";
175 if (zoneVersions
.size() <= keep
) {
176 g_log
<<Logger::Info
<<"not cleaning up"<<endl
;
179 g_log
<<Logger::Info
<<"cleaning up the oldest "<<zoneVersions
.size() - keep
<<endl
;
182 std::sort(zoneVersions
.begin(), zoneVersions
.end(), sortSOA
);
184 // And delete all the old ones
186 // Lock to ensure no one reads this.
187 std::lock_guard
<std::mutex
> guard(g_soas_mutex
);
188 for (auto iter
= zoneVersions
.cbegin(); iter
!= zoneVersions
.cend() - keep
; ++iter
) {
189 string fname
= dir
+ "/" + std::to_string(*iter
);
190 g_log
<<Logger::Debug
<<"Removing "<<fname
<<endl
;
191 unlink(fname
.c_str());
196 static shared_ptr
<SOARecordContent
> getSOAFromRecords(const records_t
& records
) {
197 for (const auto& dnsrecord
: records
) {
198 if (dnsrecord
.d_type
== QType::SOA
) {
199 auto soa
= getRR
<SOARecordContent
>(dnsrecord
);
200 if (soa
== nullptr) {
201 throw PDNSException("Unable to determine SOARecordContent from old records");
206 throw PDNSException("No SOA in supplied records");
209 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) {
210 set_difference(from
.cbegin(), from
.cend(), to
.cbegin(), to
.cend(), back_inserter(diff
->removals
), from
.value_comp());
211 set_difference(to
.cbegin(), to
.cend(), from
.cbegin(), from
.cend(), back_inserter(diff
->additions
), from
.value_comp());
212 diff
->oldSOA
= fromSOA
;
213 if (fromSOA
== nullptr) {
214 diff
->oldSOA
= getSOAFromRecords(from
);
216 diff
->newSOA
= toSOA
;
217 if (toSOA
== nullptr) {
218 diff
->newSOA
= getSOAFromRecords(to
);
222 /* you can _never_ alter the content of the resulting shared pointer */
223 static std::shared_ptr
<ixfrinfo_t
> getCurrentZoneInfo(const DNSName
& domain
)
225 std::lock_guard
<std::mutex
> guard(g_soas_mutex
);
226 return g_soas
[domain
];
229 static void updateCurrentZoneInfo(const DNSName
& domain
, std::shared_ptr
<ixfrinfo_t
>& newInfo
)
231 std::lock_guard
<std::mutex
> guard(g_soas_mutex
);
232 g_soas
[domain
] = newInfo
;
235 void updateThread(const string
& workdir
, const uint16_t& keep
, const uint16_t& axfrTimeout
) {
236 std::map
<DNSName
, time_t> lastCheck
;
238 // Initialize the serials we have
239 for (const auto &domainConfig
: g_domainConfigs
) {
240 DNSName domain
= domainConfig
.first
;
241 lastCheck
[domain
] = 0;
242 string dir
= workdir
+ "/" + domain
.toString();
244 g_log
<<Logger::Info
<<"Trying to initially load domain "<<domain
<<" from disk"<<endl
;
245 auto serial
= getSerialsFromDir(dir
);
246 shared_ptr
<SOARecordContent
> soa
;
248 string fname
= workdir
+ "/" + domain
.toString() + "/" + std::to_string(serial
);
249 loadSOAFromDisk(domain
, fname
, soa
);
251 if (soa
!= nullptr) {
252 loadZoneFromDisk(records
, fname
, domain
);
254 auto zoneInfo
= std::make_shared
<ixfrinfo_t
>();
255 zoneInfo
->latestAXFR
= std::move(records
);
257 updateCurrentZoneInfo(domain
, zoneInfo
);
259 if (soa
!= nullptr) {
260 g_log
<<Logger::Notice
<<"Loaded zone "<<domain
<<" with serial "<<soa
->d_st
.serial
<<endl
;
262 cleanUpDomain(domain
, keep
, workdir
);
264 } catch (runtime_error
&e
) {
265 // Most likely, the directory does not exist.
266 g_log
<<Logger::Info
<<e
.what()<<", attempting to create"<<endl
;
267 // Attempt to create it, if _that_ fails, there is no hope
268 if (mkdir(dir
.c_str(), 0777) == -1 && errno
!= EEXIST
) {
269 g_log
<<Logger::Error
<<"Could not create '"<<dir
<<"': "<<strerror(errno
)<<endl
;
275 g_log
<<Logger::Notice
<<"Update Thread started"<<endl
;
279 g_log
<<Logger::Notice
<<"UpdateThread stopped"<<endl
;
282 time_t now
= time(nullptr);
283 for (const auto &domainConfig
: g_domainConfigs
) {
289 DNSName domain
= domainConfig
.first
;
290 shared_ptr
<SOARecordContent
> current_soa
;
291 const auto& zoneInfo
= getCurrentZoneInfo(domain
);
292 if (zoneInfo
!= nullptr) {
293 current_soa
= zoneInfo
->soa
;
296 auto& zoneLastCheck
= lastCheck
[domain
];
297 if ((current_soa
!= nullptr && now
- zoneLastCheck
< current_soa
->d_st
.refresh
) || // Only check if we have waited `refresh` seconds
298 (current_soa
== nullptr && now
- zoneLastCheck
< 30)) { // Or if we could not get an update at all still, every 30 seconds
302 // TODO Keep track of 'down' masters
303 set
<ComboAddress
>::const_iterator
it(domainConfig
.second
.masters
.begin());
304 std::advance(it
, random() % domainConfig
.second
.masters
.size());
305 ComboAddress master
= *it
;
307 string dir
= workdir
+ "/" + domain
.toString();
308 g_log
<<Logger::Info
<<"Attempting to retrieve SOA Serial update for '"<<domain
<<"' from '"<<master
.toStringWithPort()<<"'"<<endl
;
309 shared_ptr
<SOARecordContent
> sr
;
312 auto newSerial
= getSerialFromMaster(master
, domain
, sr
); // TODO TSIG
313 if(current_soa
!= nullptr) {
314 g_log
<<Logger::Info
<<"Got SOA Serial for "<<domain
<<" from "<<master
.toStringWithPort()<<": "<< newSerial
<<", had Serial: "<<current_soa
->d_st
.serial
;
315 if (newSerial
== current_soa
->d_st
.serial
) {
316 g_log
<<Logger::Info
<<", not updating."<<endl
;
319 g_log
<<Logger::Info
<<", will update."<<endl
;
321 } catch (runtime_error
&e
) {
322 g_log
<<Logger::Warning
<<"Unable to get SOA serial update for '"<<domain
<<"' from master "<<master
.toStringWithPort()<<": "<<e
.what()<<endl
;
325 // Now get the full zone!
326 g_log
<<Logger::Info
<<"Attempting to receive full zonedata for '"<<domain
<<"'"<<endl
;
327 ComboAddress local
= master
.isIPv4() ? ComboAddress("0.0.0.0") : ComboAddress("::");
331 shared_ptr
<SOARecordContent
> soa
;
334 AXFRRetriever
axfr(master
, domain
, tt
, &local
);
335 unsigned int nrecords
=0;
337 vector
<DNSRecord
> chunk
;
338 time_t t_start
= time(nullptr);
339 time_t axfr_now
= time(nullptr);
340 while(axfr
.getChunk(nop
, &chunk
, (axfr_now
- t_start
+ axfrTimeout
))) {
341 for(auto& dr
: chunk
) {
342 if(dr
.d_type
== QType::TSIG
)
344 dr
.d_name
.makeUsRelative(domain
);
347 if (dr
.d_type
== QType::SOA
) {
348 soa
= getRR
<SOARecordContent
>(dr
);
351 axfr_now
= time(nullptr);
352 if (axfr_now
- t_start
> axfrTimeout
) {
353 throw PDNSException("Total AXFR time exceeded!");
356 if (soa
== nullptr) {
357 g_log
<<Logger::Warning
<<"No SOA was found in the AXFR of "<<domain
<<endl
;
360 g_log
<<Logger::Notice
<<"Retrieved all zone data for "<<domain
<<". Received "<<nrecords
<<" records."<<endl
;
361 } catch (PDNSException
&e
) {
362 g_log
<<Logger::Warning
<<"Could not retrieve AXFR for '"<<domain
<<"': "<<e
.reason
<<endl
;
364 } catch (runtime_error
&e
) {
365 g_log
<<Logger::Warning
<<"Could not retrieve AXFR for zone '"<<domain
<<"': "<<e
.what()<<endl
;
371 writeZoneToDisk(records
, domain
, dir
);
372 g_log
<<Logger::Notice
<<"Wrote zonedata for "<<domain
<<" with serial "<<soa
->d_st
.serial
<<" to "<<dir
<<endl
;
374 const auto oldZoneInfo
= getCurrentZoneInfo(domain
);
375 auto zoneInfo
= std::make_shared
<ixfrinfo_t
>();
377 if (oldZoneInfo
&& !oldZoneInfo
->latestAXFR
.empty()) {
378 auto diff
= std::make_shared
<ixfrdiff_t
>();
379 zoneInfo
->ixfrDiffs
= oldZoneInfo
->ixfrDiffs
;
380 g_log
<<Logger::Debug
<<"Calculating diff for "<<domain
<<endl
;
381 makeIXFRDiff(oldZoneInfo
->latestAXFR
, records
, diff
, oldZoneInfo
->soa
, soa
);
382 g_log
<<Logger::Debug
<<"Calculated diff for "<<domain
<<", we had "<<diff
->removals
.size()<<" removals and "<<diff
->additions
.size()<<" additions"<<endl
;
383 zoneInfo
->ixfrDiffs
.push_back(std::move(diff
));
386 // Clean up the diffs
387 while (zoneInfo
->ixfrDiffs
.size() > keep
) {
388 zoneInfo
->ixfrDiffs
.erase(zoneInfo
->ixfrDiffs
.begin());
391 g_log
<<Logger::Debug
<<"Zone "<<domain
<<" previously contained "<<(oldZoneInfo
? oldZoneInfo
->latestAXFR
.size() : 0)<<" entries, "<<records
.size()<<" now"<<endl
;
392 zoneInfo
->latestAXFR
= std::move(records
);
394 updateCurrentZoneInfo(domain
, zoneInfo
);
395 } catch (PDNSException
&e
) {
396 g_log
<<Logger::Warning
<<"Could not save zone '"<<domain
<<"' to disk: "<<e
.reason
<<endl
;
397 } catch (runtime_error
&e
) {
398 g_log
<<Logger::Warning
<<"Could not save zone '"<<domain
<<"' to disk: "<<e
.what()<<endl
;
401 // Now clean up the directory
402 cleanUpDomain(domain
, keep
, workdir
);
403 } /* for (const auto &domain : domains) */
408 bool checkQuery(const MOADNSParser
& mdp
, const ComboAddress
& saddr
, const bool udp
= true, const string
& logPrefix
="") {
409 vector
<string
> info_msg
;
411 g_log
<<Logger::Debug
<<logPrefix
<<"Had "<<mdp
.d_qname
<<"|"<<QType(mdp
.d_qtype
).getName()<<" query from "<<saddr
.toStringWithPort()<<endl
;
413 if (udp
&& mdp
.d_qtype
!= QType::SOA
&& mdp
.d_qtype
!= QType::IXFR
) {
414 info_msg
.push_back("QType is unsupported (" + QType(mdp
.d_qtype
).getName() + " is not in {SOA,IXFR}");
417 if (!udp
&& mdp
.d_qtype
!= QType::SOA
&& mdp
.d_qtype
!= QType::IXFR
&& mdp
.d_qtype
!= QType::AXFR
) {
418 info_msg
.push_back("QType is unsupported (" + QType(mdp
.d_qtype
).getName() + " is not in {SOA,IXFR,AXFR}");
422 if (g_domainConfigs
.find(mdp
.d_qname
) == g_domainConfigs
.end()) {
423 info_msg
.push_back("Domain name '" + mdp
.d_qname
.toLogString() + "' is not configured for distribution");
426 const auto zoneInfo
= getCurrentZoneInfo(mdp
.d_qname
);
427 if (zoneInfo
== nullptr) {
428 info_msg
.push_back("Domain has not been transferred yet");
432 if (!info_msg
.empty()) {
433 g_log
<<Logger::Warning
<<logPrefix
<<"Ignoring "<<mdp
.d_qname
<<"|"<<QType(mdp
.d_qtype
).getName()<<" query from "<<saddr
.toStringWithPort();
434 g_log
<<Logger::Warning
<<": ";
436 for (const auto& s
: info_msg
) {
438 g_log
<<Logger::Warning
<<", ";
441 g_log
<<Logger::Warning
<<s
;
443 g_log
<<Logger::Warning
<<endl
;
451 * Returns a vector<uint8_t> that represents the full response to a SOA
452 * query. QNAME is read from mdp.
454 bool makeSOAPacket(const MOADNSParser
& mdp
, vector
<uint8_t>& packet
) {
456 auto zoneInfo
= getCurrentZoneInfo(mdp
.d_qname
);
457 if (zoneInfo
== nullptr) {
461 DNSPacketWriter
pw(packet
, mdp
.d_qname
, mdp
.d_qtype
);
462 pw
.getHeader()->id
= mdp
.d_header
.id
;
463 pw
.getHeader()->rd
= mdp
.d_header
.rd
;
464 pw
.getHeader()->qr
= 1;
466 pw
.startRecord(mdp
.d_qname
, QType::SOA
);
467 zoneInfo
->soa
->toPacket(pw
);
473 vector
<uint8_t> getSOAPacket(const MOADNSParser
& mdp
, const shared_ptr
<SOARecordContent
>& soa
) {
474 vector
<uint8_t> packet
;
475 DNSPacketWriter
pw(packet
, mdp
.d_qname
, mdp
.d_qtype
);
476 pw
.getHeader()->id
= mdp
.d_header
.id
;
477 pw
.getHeader()->rd
= mdp
.d_header
.rd
;
478 pw
.getHeader()->qr
= 1;
481 pw
.startRecord(mdp
.d_qname
, QType::SOA
);
487 bool makeAXFRPackets(const MOADNSParser
& mdp
, vector
<vector
<uint8_t>>& packets
) {
488 /* we get a shared pointer of the zone info that we can't modify, ever.
489 A newer one may arise in the meantime, but this one will stay valid
492 auto zoneInfo
= getCurrentZoneInfo(mdp
.d_qname
);
493 if (zoneInfo
== nullptr) {
497 shared_ptr
<SOARecordContent
> soa
= zoneInfo
->soa
;
498 const records_t
& records
= zoneInfo
->latestAXFR
;
499 packets
.reserve(packets
.size() + /* SOAs */ 2 + records
.size());
502 const auto soaPacket
= getSOAPacket(mdp
, soa
);
503 packets
.push_back(soaPacket
);
505 for (auto const &record
: records
) {
506 if (record
.d_type
== QType::SOA
) {
509 vector
<uint8_t> packet
;
510 DNSPacketWriter
pw(packet
, mdp
.d_qname
, mdp
.d_qtype
);
511 pw
.getHeader()->id
= mdp
.d_header
.id
;
512 pw
.getHeader()->rd
= mdp
.d_header
.rd
;
513 pw
.getHeader()->qr
= 1;
514 pw
.startRecord(record
.d_name
+ mdp
.d_qname
, record
.d_type
);
515 record
.d_content
->toPacket(pw
);
517 packets
.push_back(packet
);
521 packets
.push_back(soaPacket
);
526 void makeXFRPacketsFromDNSRecords(const MOADNSParser
& mdp
, const vector
<DNSRecord
>& records
, vector
<vector
<uint8_t>>& packets
) {
528 for(const auto& r
: records
) {
529 if (r
.d_type
== QType::SOA
) {
533 vector
<uint8_t> packet
;
534 DNSPacketWriter
pw(packet
, mdp
.d_qname
, mdp
.d_qtype
);
535 pw
.getHeader()->id
= mdp
.d_header
.id
;
536 pw
.getHeader()->rd
= mdp
.d_header
.rd
;
537 pw
.getHeader()->qr
= 1;
538 pw
.startRecord(r
.d_name
+ mdp
.d_qname
, r
.d_type
);
539 r
.d_content
->toPacket(pw
);
541 packets
.push_back(packet
);
545 /* Produces an IXFR if one can be made according to the rules in RFC 1995 and
546 * creates a SOA or AXFR packet when required by the RFC.
548 bool makeIXFRPackets(const MOADNSParser
& mdp
, const shared_ptr
<SOARecordContent
>& clientSOA
, vector
<vector
<uint8_t>>& packets
) {
549 vector
<std::shared_ptr
<ixfrdiff_t
>> toSend
;
551 /* we get a shared pointer of the zone info that we can't modify, ever.
552 A newer one may arise in the meantime, but this one will stay valid
555 auto zoneInfo
= getCurrentZoneInfo(mdp
.d_qname
);
556 if (zoneInfo
== nullptr) {
560 uint32_t ourLatestSerial
= zoneInfo
->soa
->d_st
.serial
;
562 if (rfc1982LessThan(ourLatestSerial
, clientSOA
->d_st
.serial
) || ourLatestSerial
== clientSOA
->d_st
.serial
) {
563 /* RFC 1995 Section 2
564 * If an IXFR query with the same or newer version number than that of
565 * the server is received, it is replied to with a single SOA record of
566 * the server's current version, just as in AXFR.
568 vector
<uint8_t> packet
;
569 bool ret
= makeSOAPacket(mdp
, packet
);
571 packets
.push_back(packet
);
576 // as we use push_back in the updater, we know the vector is sorted as oldest first
577 bool shouldAdd
= false;
578 // Get all relevant IXFR differences
579 for (const auto& diff
: zoneInfo
->ixfrDiffs
) {
581 toSend
.push_back(diff
);
584 if (diff
->oldSOA
->d_st
.serial
== clientSOA
->d_st
.serial
) {
585 toSend
.push_back(diff
);
586 // Add all consecutive diffs
591 if (toSend
.empty()) {
592 g_log
<<Logger::Warning
<<"No IXFR available from serial "<<clientSOA
->d_st
.serial
<<" for zone "<<mdp
.d_qname
<<", attempting to send AXFR"<<endl
;
593 return makeAXFRPackets(mdp
, packets
);
596 for (const auto& diff
: toSend
) {
597 /* An IXFR packet's ANSWER section looks as follows:
600 * ... removed records ...
602 * ... added records ...
605 packets
.reserve(packets
.size() + /* SOAs */ 4 + diff
->removals
.size() + diff
->additions
.size());
607 packets
.push_back(getSOAPacket(mdp
, diff
->newSOA
));
608 packets
.push_back(getSOAPacket(mdp
, diff
->oldSOA
));
609 makeXFRPacketsFromDNSRecords(mdp
, diff
->removals
, packets
);
610 packets
.push_back(getSOAPacket(mdp
, diff
->newSOA
));
611 makeXFRPacketsFromDNSRecords(mdp
, diff
->additions
, packets
);
612 packets
.push_back(getSOAPacket(mdp
, diff
->newSOA
));
618 bool allowedByACL(const ComboAddress
& addr
) {
619 return g_acl
.match(addr
);
622 void handleUDPRequest(int fd
, boost::any
&) {
623 // TODO make the buffer-size configurable
626 socklen_t fromlen
= sizeof(saddr
);
627 int res
= recvfrom(fd
, buf
, sizeof(buf
), 0, (struct sockaddr
*) &saddr
, &fromlen
);
630 g_log
<<Logger::Warning
<<"Got an empty message from "<<saddr
.toStringWithPort()<<endl
;
635 auto savedErrno
= errno
;
636 g_log
<<Logger::Warning
<<"Could not read message from "<<saddr
.toStringWithPort()<<": "<<strerror(savedErrno
)<<endl
;
640 if (saddr
== ComboAddress("0.0.0.0", 0)) {
641 g_log
<<Logger::Warning
<<"Could not determine source of message"<<endl
;
645 if (!allowedByACL(saddr
)) {
646 g_log
<<Logger::Warning
<<"UDP query from "<<saddr
.toString()<<" is not allowed, dropping"<<endl
;
650 MOADNSParser
mdp(true, string(buf
, res
));
651 if (!checkQuery(mdp
, saddr
)) {
655 /* RFC 1995 Section 2
656 * Transport of a query may be by either UDP or TCP. If an IXFR query
657 * is via UDP, the IXFR server may attempt to reply using UDP if the
658 * entire response can be contained in a single DNS packet. If the UDP
659 * reply does not fit, the query is responded to with a single SOA
660 * record of the server's current version to inform the client that a
661 * TCP query should be initiated.
663 * Let's not complicate this with IXFR over UDP (and looking if we need to truncate etc).
664 * Just send the current SOA and let the client try over TCP
666 vector
<uint8_t> packet
;
667 makeSOAPacket(mdp
, packet
);
668 if(sendto(fd
, &packet
[0], packet
.size(), 0, (struct sockaddr
*) &saddr
, fromlen
) < 0) {
669 auto savedErrno
= errno
;
670 g_log
<<Logger::Warning
<<"Could not send reply for "<<mdp
.d_qname
<<"|"<<QType(mdp
.d_qtype
).getName()<<" to "<<saddr
.toStringWithPort()<<": "<<strerror(savedErrno
)<<endl
;
675 void handleTCPRequest(int fd
, boost::any
&) {
680 cfd
= SAccept(fd
, saddr
);
682 } catch(runtime_error
&e
) {
683 g_log
<<Logger::Error
<<e
.what()<<endl
;
687 if (saddr
== ComboAddress("0.0.0.0", 0)) {
688 g_log
<<Logger::Warning
<<"Could not determine source of message"<<endl
;
693 if (!allowedByACL(saddr
)) {
694 g_log
<<Logger::Warning
<<"TCP query from "<<saddr
.toString()<<" is not allowed, dropping"<<endl
;
700 std::lock_guard
<std::mutex
> lg(g_tcpRequestFDsMutex
);
701 g_tcpRequestFDs
.push({cfd
, saddr
});
703 g_tcpHandlerCV
.notify_one();
706 /* Thread to handle TCP traffic
708 void tcpWorker(int tid
) {
709 string prefix
= "TCP Worker " + std::to_string(tid
) + ": ";
712 g_log
<<Logger::Debug
<<prefix
<<"ready for a new request!"<<endl
;
713 std::unique_lock
<std::mutex
> lk(g_tcpRequestFDsMutex
);
714 g_tcpHandlerCV
.wait(lk
, []{return g_tcpRequestFDs
.size() || g_exiting
;});
716 g_log
<<Logger::Debug
<<prefix
<<"Stopping thread"<<endl
;
719 g_log
<<Logger::Debug
<<prefix
<<"Going to handle a query"<<endl
;
720 auto request
= g_tcpRequestFDs
.front();
721 g_tcpRequestFDs
.pop();
724 int cfd
= request
.first
;
725 ComboAddress saddr
= request
.second
;
731 readn2(cfd
, &toRead
, sizeof(toRead
));
732 toRead
= std::min(ntohs(toRead
), static_cast<uint16_t>(sizeof(buf
)));
733 res
= readn2WithTimeout(cfd
, &buf
, toRead
, 2);
734 g_log
<<Logger::Debug
<<prefix
<<"Had message of "<<std::to_string(toRead
)<<" bytes from "<<saddr
.toStringWithPort()<<endl
;
735 } catch (runtime_error
&e
) {
736 g_log
<<Logger::Warning
<<prefix
<<"Could not read message from "<<saddr
.toStringWithPort()<<": "<<e
.what()<<endl
;
742 MOADNSParser
mdp(true, string(buf
, res
));
744 if (!checkQuery(mdp
, saddr
, false, prefix
)) {
749 vector
<vector
<uint8_t>> packets
;
750 if (mdp
.d_qtype
== QType::SOA
) {
751 vector
<uint8_t> packet
;
752 bool ret
= makeSOAPacket(mdp
, packet
);
757 packets
.push_back(packet
);
760 if (mdp
.d_qtype
== QType::AXFR
) {
761 if (!makeAXFRPackets(mdp
, packets
)) {
767 if (mdp
.d_qtype
== QType::IXFR
) {
768 /* RFC 1995 section 3:
769 * The IXFR query packet format is the same as that of a normal DNS
770 * query, but with the query type being IXFR and the authority section
771 * containing the SOA record of client's version of the zone.
773 shared_ptr
<SOARecordContent
> clientSOA
;
774 for (auto &answer
: mdp
.d_answers
) {
775 // from dnsparser.hh:
776 // typedef vector<pair<DNSRecord, uint16_t > > answers_t;
777 if (answer
.first
.d_type
== QType::SOA
&& answer
.first
.d_place
== DNSResourceRecord::AUTHORITY
) {
778 clientSOA
= getRR
<SOARecordContent
>(answer
.first
);
779 if (clientSOA
!= nullptr) {
783 } /* for (auto const &answer : mdp.d_answers) */
785 if (clientSOA
== nullptr) {
786 g_log
<<Logger::Warning
<<prefix
<<"IXFR request packet did not contain a SOA record in the AUTHORITY section"<<endl
;
791 if (!makeIXFRPackets(mdp
, clientSOA
, packets
)) {
795 } /* if (mdp.d_qtype == QType::IXFR) */
797 g_log
<<Logger::Debug
<<prefix
<<"Sending "<<packets
.size()<<" packets to "<<saddr
.toStringWithPort()<<endl
;
798 for (const auto& packet
: packets
) {
800 sendBuf
[0]=packet
.size()/256;
801 sendBuf
[1]=packet
.size()%256;
803 ssize_t send
= writen2(cfd
, sendBuf
, 2);
804 send
+= writen2(cfd
, &packet
[0], packet
.size());
807 } catch (MOADNSException
&e
) {
808 g_log
<<Logger::Warning
<<prefix
<<"Could not parse DNS packet from "<<saddr
.toStringWithPort()<<": "<<e
.what()<<endl
;
809 } catch (runtime_error
&e
) {
810 g_log
<<Logger::Warning
<<prefix
<<"Could not write reply to "<<saddr
.toStringWithPort()<<": "<<e
.what()<<endl
;
821 /* Parses the configuration file in configpath into config, adding defaults for
822 * missing parameters (if applicable), returning true if the config file was
823 * good, false otherwise. Will log all issues with the config
825 bool parseAndCheckConfig(const string
& configpath
, YAML::Node
& config
) {
826 g_log
<<Logger::Info
<<"Loading configuration file from "<<configpath
<<endl
;
828 config
= YAML::LoadFile(configpath
);
829 } catch (const runtime_error
&e
) {
830 g_log
<<Logger::Error
<<"Unable to load configuration file '"<<configpath
<<"': "<<e
.what()<<endl
;
836 if (config
["keep"]) {
838 config
["keep"].as
<uint16_t>();
839 } catch (const runtime_error
&e
) {
840 g_log
<<Logger::Error
<<"Unable to read 'keep' value: "<<e
.what()<<endl
;
847 if (config
["axfr-timeout"]) {
849 config
["axfr-timeout"].as
<uint16_t>();
850 } catch (const runtime_error
&e
) {
851 g_log
<<Logger::Error
<<"Unable to read 'axfr-timeout' value: "<<e
.what()<<endl
;
854 config
["axfr-timeout"] = 20;
857 if (config
["tcp-in-threads"]) {
859 config
["tcp-in-threads"].as
<uint16_t>();
860 } catch (const runtime_error
&e
) {
861 g_log
<<Logger::Error
<<"Unable to read 'tcp-in-threads' value: "<<e
.what()<<endl
;
864 config
["tcp-in-threads"] = 10;
867 if (config
["listen"]) {
869 config
["listen"].as
<vector
<ComboAddress
>>();
870 } catch (const runtime_error
&e
) {
871 g_log
<<Logger::Error
<<"Unable to read 'listen' value: "<<e
.what()<<endl
;
875 config
["listen"].push_back("127.0.0.1:53");
876 config
["listen"].push_back("[::1]:53");
881 config
["acl"].as
<vector
<string
>>();
882 } catch (const runtime_error
&e
) {
883 g_log
<<Logger::Error
<<"Unable to read 'acl' value: "<<e
.what()<<endl
;
887 config
["acl"].push_back("127.0.0.0/8");
888 config
["acl"].push_back("::1/128");
891 if (config
["work-dir"]) {
893 config
["work-dir"].as
<string
>();
894 } catch(const runtime_error
&e
) {
895 g_log
<<Logger::Error
<<"Unable to read 'work-dir' value: "<<e
.what()<<endl
;
900 config
["work-dir"] = getcwd(tmp
, sizeof(tmp
)) ? string(tmp
) : "";;
905 config
["uid"].as
<string
>();
906 } catch(const runtime_error
&e
) {
907 g_log
<<Logger::Error
<<"Unable to read 'uid' value: "<<e
.what()<<endl
;
914 config
["gid"].as
<string
>();
915 } catch(const runtime_error
&e
) {
916 g_log
<<Logger::Error
<<"Unable to read 'gid' value: "<<e
.what()<<endl
;
921 if (config
["domains"]) {
922 if (config
["domains"].size() == 0) {
923 g_log
<<Logger::Error
<<"No domains configured"<<endl
;
926 for (auto const &domain
: config
["domains"]) {
928 if (!domain
["domain"]) {
929 g_log
<<Logger::Error
<<"An entry in 'domains' is missing a 'domain' key!"<<endl
;
933 domain
["domain"].as
<DNSName
>();
934 } catch (const runtime_error
&e
) {
935 g_log
<<Logger::Error
<<"Unable to read domain '"<<domain
["domain"].as
<string
>()<<"': "<<e
.what()<<endl
;
938 if (!domain
["master"]) {
939 g_log
<<Logger::Error
<<"Domain '"<<domain
["domain"].as
<string
>()<<"' has no master configured!"<<endl
;
943 domain
["master"].as
<ComboAddress
>();
944 } catch (const runtime_error
&e
) {
945 g_log
<<Logger::Error
<<"Unable to read domain '"<<domain
["domain"].as
<string
>()<<"' master address: "<<e
.what()<<endl
;
950 g_log
<<Logger::Error
<<"No domains configured"<<endl
;
957 int main(int argc
, char** argv
) {
958 g_log
.setLoglevel(Logger::Notice
);
959 g_log
.toConsole(Logger::Notice
);
960 g_log
.setPrefixed(true);
961 g_log
.disableSyslog(true);
962 g_log
.setTimestamps(false);
963 po::variables_map g_vm
;
965 po::options_description
desc("IXFR distribution tool");
967 ("help", "produce help message")
968 ("version", "Display the version of ixfrdist")
969 ("verbose", "Be verbose")
970 ("debug", "Be even more verbose")
971 ("config", po::value
<string
>()->default_value(SYSCONFDIR
+ string("/ixfrdist.yml")), "Configuration file to use")
974 po::store(po::command_line_parser(argc
, argv
).options(desc
).run(), g_vm
);
977 if (g_vm
.count("help") > 0) {
982 if (g_vm
.count("version") > 0) {
983 cout
<<"ixfrdist "<<VERSION
<<endl
;
986 } catch (po::error
&e
) {
987 g_log
<<Logger::Error
<<e
.what()<<". See `ixfrdist --help` for valid options"<<endl
;
988 return(EXIT_FAILURE
);
991 bool had_error
= false;
993 if (g_vm
.count("verbose")) {
994 g_log
.setLoglevel(Logger::Info
);
995 g_log
.toConsole(Logger::Info
);
998 if (g_vm
.count("debug") > 0) {
999 g_log
.setLoglevel(Logger::Debug
);
1000 g_log
.toConsole(Logger::Debug
);
1003 g_log
<<Logger::Notice
<<"IXFR distributor version "<<VERSION
<<" starting up!"<<endl
;
1006 if (!parseAndCheckConfig(g_vm
["config"].as
<string
>(), config
)) {
1007 // parseAndCheckConfig already logged whatever was wrong
1008 return EXIT_FAILURE
;
1011 /* From hereon out, we known that all the values in config are valid. */
1013 for (auto const &domain
: config
["domains"]) {
1014 set
<ComboAddress
> s
;
1015 s
.insert(domain
["master"].as
<ComboAddress
>());
1016 g_domainConfigs
[domain
["domain"].as
<DNSName
>()].masters
= s
;
1019 for (const auto &addr
: config
["acl"].as
<vector
<string
>>()) {
1021 g_acl
.addMask(addr
);
1022 } catch (const NetmaskException
&e
) {
1023 g_log
<<Logger::Error
<<e
.reason
<<endl
;
1027 g_log
<<Logger::Notice
<<"ACL set to "<<g_acl
.toString()<<"."<<endl
;
1029 FDMultiplexer
* fdm
= FDMultiplexer::getMultiplexerSilent();
1030 if (fdm
== nullptr) {
1031 g_log
<<Logger::Error
<<"Could not enable a multiplexer for the listen sockets!"<<endl
;
1032 return EXIT_FAILURE
;
1035 set
<int> allSockets
;
1036 for (const auto& addr
: config
["listen"].as
<vector
<ComboAddress
>>()) {
1037 for (const auto& stype
: {SOCK_DGRAM
, SOCK_STREAM
}) {
1039 int s
= SSocket(addr
.sin4
.sin_family
, stype
, 0);
1043 if (stype
== SOCK_STREAM
) {
1044 SListen(s
, 30); // TODO make this configurable
1046 fdm
->addReadFD(s
, stype
== SOCK_DGRAM
? handleUDPRequest
: handleTCPRequest
);
1047 allSockets
.insert(s
);
1048 } catch(runtime_error
&e
) {
1049 g_log
<<Logger::Error
<<e
.what()<<endl
;
1058 if (config
["gid"]) {
1059 string gid
= config
["gid"].as
<string
>();
1060 if (!(newgid
= atoi(gid
.c_str()))) {
1061 struct group
*gr
= getgrnam(gid
.c_str());
1062 if (gr
== nullptr) {
1063 g_log
<<Logger::Error
<<"Can not determine group-id for gid "<<gid
<<endl
;
1066 newgid
= gr
->gr_gid
;
1069 g_log
<<Logger::Notice
<<"Dropping effective group-id to "<<newgid
<<endl
;
1070 if (setgid(newgid
) < 0) {
1071 g_log
<<Logger::Error
<<"Could not set group id to "<<newgid
<<": "<<stringerror()<<endl
;
1078 if (config
["uid"]) {
1079 string uid
= config
["uid"].as
<string
>();
1080 if (!(newuid
= atoi(uid
.c_str()))) {
1081 struct passwd
*pw
= getpwnam(uid
.c_str());
1082 if (pw
== nullptr) {
1083 g_log
<<Logger::Error
<<"Can not determine user-id for uid "<<uid
<<endl
;
1086 newuid
= pw
->pw_uid
;
1090 struct passwd
*pw
= getpwuid(newuid
);
1091 if (pw
== nullptr) {
1092 if (setgroups(0, nullptr) < 0) {
1093 g_log
<<Logger::Error
<<"Unable to drop supplementary gids: "<<stringerror()<<endl
;
1097 if (initgroups(pw
->pw_name
, newgid
) < 0) {
1098 g_log
<<Logger::Error
<<"Unable to set supplementary groups: "<<stringerror()<<endl
;
1103 g_log
<<Logger::Notice
<<"Dropping effective user-id to "<<newuid
<<endl
;
1104 if (setuid(newuid
) < 0) {
1105 g_log
<<Logger::Error
<<"Could not set user id to "<<newuid
<<": "<<stringerror()<<endl
;
1111 // We have already sent the errors to stderr, just die
1112 return EXIT_FAILURE
;
1115 // It all starts here
1116 signal(SIGTERM
, handleSignal
);
1117 signal(SIGINT
, handleSignal
);
1118 signal(SIGPIPE
, SIG_IGN
);
1120 // Init the things we need
1125 std::thread
ut(updateThread
,
1126 config
["work-dir"].as
<string
>(),
1127 config
["keep"].as
<uint16_t>(),
1128 config
["axfr-timeout"].as
<uint16_t>());
1130 vector
<std::thread
> tcpHandlers
;
1131 tcpHandlers
.reserve(config
["tcp-in-threads"].as
<uint16_t>());
1132 for (size_t i
= 0; i
< tcpHandlers
.capacity(); ++i
) {
1133 tcpHandlers
.push_back(std::thread(tcpWorker
, i
));
1138 gettimeofday(&now
, 0);
1141 g_log
<<Logger::Debug
<<"Closing listening sockets"<<endl
;
1142 for (const int& fd
: allSockets
) {
1145 } catch(PDNSException
&e
) {
1146 g_log
<<Logger::Error
<<e
.reason
<<endl
;
1152 g_log
<<Logger::Debug
<<"Waiting for al threads to stop"<<endl
;
1153 g_tcpHandlerCV
.notify_all();
1155 for (auto &t
: tcpHandlers
) {
1158 g_log
<<Logger::Notice
<<"IXFR distributor stopped"<<endl
;
1159 return EXIT_SUCCESS
;