From f775768e5e52462be002c7e42a2dbbe017246ce4 Mon Sep 17 00:00:00 2001 From: pdns-recursor packagers Date: Mon, 18 Mar 2024 23:34:27 +0100 Subject: [PATCH] ns-ampl-4.1.15 =================================================================== Gbp-Pq: Name ns-ampl-4.1.15.diff --- pdns_recursor.cc | 2 ++ syncres.cc | 28 ++++++++++++++++++++++++---- syncres.hh | 5 +++-- test-syncres_cc.cc | 45 ++++++++++++++++++++++++++++++++++++++++++++- 4 files changed, 73 insertions(+), 7 deletions(-) diff --git a/pdns_recursor.cc b/pdns_recursor.cc index ce5394e..808cc2b 100644 --- a/pdns_recursor.cc +++ b/pdns_recursor.cc @@ -3073,6 +3073,7 @@ static int serviceMain(int argc, char*argv[]) SyncRes::s_serverdownthrottletime=::arg().asNum("server-down-throttle-time"); SyncRes::s_serverID=::arg()["server-id"]; SyncRes::s_maxqperq=::arg().asNum("max-qperq"); + SyncRes::s_maxnsaddressqperq=::arg().asNum("max-ns-address-qperq"); SyncRes::s_maxtotusec=1000*::arg().asNum("max-total-msec"); SyncRes::s_maxdepth=::arg().asNum("max-recursion-depth"); SyncRes::s_rootNXTrust = ::arg().mustDo( "root-nx-trust"); @@ -3553,6 +3554,7 @@ int main(int argc, char **argv) ::arg().set("edns-outgoing-bufsize", "Outgoing EDNS buffer size")="1680"; ::arg().set("minimum-ttl-override", "Set under adverse conditions, a minimum TTL")="0"; ::arg().set("max-qperq", "Maximum outgoing queries per query")="50"; + ::arg().set("max-ns-address-qperq", "Maximum outgoing NS address queries per query")="10"; ::arg().set("max-total-msec", "Maximum total wall-clock time per query in milliseconds, 0 for unlimited")="7000"; ::arg().set("max-recursion-depth", "Maximum number of internal recursion calls per query, 0 for unlimited")="40"; ::arg().set("max-udp-queries-per-round", "Maximum number of UDP queries processed per recvmsg() round, before returning back to normal processing")="10000"; diff --git a/syncres.cc b/syncres.cc index 2b00021..8fc5e6d 100644 --- a/syncres.cc +++ b/syncres.cc @@ -49,6 +49,7 @@ SyncRes::LogMode SyncRes::s_lm; unsigned int SyncRes::s_maxnegttl; unsigned int SyncRes::s_maxcachettl; unsigned int SyncRes::s_maxqperq; +unsigned int SyncRes::s_maxnsaddressqperq; unsigned int SyncRes::s_maxtotusec; unsigned int SyncRes::s_maxdepth; unsigned int SyncRes::s_minimumTTL; @@ -658,7 +659,7 @@ struct speedOrderCA /** This function explicitly goes out for A or AAAA addresses */ -vector SyncRes::getAddrs(const DNSName &qname, unsigned int depth, set& beenthere, bool cacheOnly) +vector SyncRes::getAddrs(const DNSName &qname, unsigned int depth, set& beenthere, bool cacheOnly, unsigned int& addressQueriesForNS) { typedef vector res_t; res_t res; @@ -670,6 +671,7 @@ vector SyncRes::getAddrs(const DNSName &qname, unsigned int depth, bool oldCacheOnly = d_cacheonly; bool oldRequireAuthData = d_requireAuthData; bool oldValidationRequested = d_DNSSECValidationRequested; + const unsigned int startqueries = d_outqueries; d_requireAuthData = false; d_DNSSECValidationRequested = false; d_cacheonly = cacheOnly; @@ -719,6 +721,10 @@ vector SyncRes::getAddrs(const DNSName &qname, unsigned int depth, } } + if (ret.empty() && d_outqueries > startqueries) { + // We did 1 or more outgoing queries to resolve this NS name but returned empty handed + addressQueriesForNS++; + } d_requireAuthData = oldRequireAuthData; d_DNSSECValidationRequested = oldValidationRequested; d_cacheonly = oldCacheOnly; @@ -1425,13 +1431,13 @@ bool SyncRes::nameserverIPBlockedByRPZ(const DNSFilterEngine& dfe, const ComboAd return false; } -vector SyncRes::retrieveAddressesForNS(const std::string& prefix, const DNSName& qname, vector::const_iterator& tns, const unsigned int depth, set& beenthere, const vector& rnameservers, NsSet& nameservers, bool& sendRDQuery, bool& pierceDontQuery, bool& flawedNSSet, bool cacheOnly) +vector SyncRes::retrieveAddressesForNS(const std::string& prefix, const DNSName& qname, vector::const_iterator& tns, const unsigned int depth, set& beenthere, const vector& rnameservers, NsSet& nameservers, bool& sendRDQuery, bool& pierceDontQuery, bool& flawedNSSet, bool cacheOnly, unsigned int& retrieveAddressesForNS) { vector result; if(!tns->empty()) { LOG(prefix< rnameservers = shuffleInSpeedOrder(nameservers, doLog() ? (prefix+qname.toString()+": ") : string() ); + // We allow s_maxnsaddressqperq (default 10) queries with empty responses when resolving NS names. + // If a zone publishes many (more than s_maxnsaddressqperq) NS records, we allow less. + // This is to "punish" zones that publish many non-resolving NS names. + // We always allow 5 NS name resolving attempts with empty results. + unsigned int nsLimit = s_maxnsaddressqperq; + if (rnameservers.size() > nsLimit) { + int newLimit = static_cast(nsLimit) - (rnameservers.size() - nsLimit); + nsLimit = std::max(5, newLimit); + } + for(auto tns=rnameservers.cbegin();;++tns) { + if (addressQueriesForNS >= nsLimit) { + throw ImmediateServFailException(std::to_string(nsLimit)+" (adjusted max-ns-address-qperq) or more queries with empty results for NS addresses sent resolving "+qname.toLogString()); + } if(tns==rnameservers.cend()) { LOG(prefix< shuffleInSpeedOrder(NsSet &nameservers, const string &prefix); bool moreSpecificThan(const DNSName& a, const DNSName &b) const; - vector getAddrs(const DNSName &qname, unsigned int depth, set& beenthere, bool cacheOnly); + vector getAddrs(const DNSName &qname, unsigned int depth, set& beenthere, bool cacheOnly, unsigned int& addressQueriesForNS); bool nameserversBlockedByRPZ(const DNSFilterEngine& dfe, const NsSet& nameservers); bool nameserverIPBlockedByRPZ(const DNSFilterEngine& dfe, const ComboAddress&); bool throttledOrBlocked(const std::string& prefix, const ComboAddress& remoteIP, const DNSName& qname, const QType& qtype, bool pierceDontQuery); - vector retrieveAddressesForNS(const std::string& prefix, const DNSName& qname, vector::const_iterator& tns, const unsigned int depth, set& beenthere, const vector& rnameservers, NsSet& nameservers, bool& sendRDQuery, bool& pierceDontQuery, bool& flawedNSSet, bool cacheOnly); + vector retrieveAddressesForNS(const std::string& prefix, const DNSName& qname, vector::const_iterator& tns, const unsigned int depth, set& beenthere, const vector& rnameservers, NsSet& nameservers, bool& sendRDQuery, bool& pierceDontQuery, bool& flawedNSSet, bool cacheOnly, unsigned int& addressQueriesForNS); RCode::rcodes_ updateCacheFromRecords(unsigned int depth, LWResult& lwr, const DNSName& qname, const QType& qtype, const DNSName& auth, bool wasForwarded, const boost::optional, vState& state, bool& needWildcardProof, unsigned int& wildcardLabelsCount, bool sendRDQuery); bool processRecords(const std::string& prefix, const DNSName& qname, const QType& qtype, const DNSName& auth, LWResult& lwr, const bool sendRDQuery, vector& ret, set& nsset, DNSName& newtarget, DNSName& newauth, bool& realreferral, bool& negindic, vState& state, const bool needWildcardProof, const unsigned int wildcardLabelsCount); diff --git a/test-syncres_cc.cc b/test-syncres_cc.cc index 44ca74b..a6cea30 100644 --- a/test-syncres_cc.cc +++ b/test-syncres_cc.cc @@ -119,7 +119,8 @@ static void init(bool debug=false) t_RC = std::unique_ptr(new MemRecursorCache()); SyncRes::s_maxqperq = 50; - SyncRes::s_maxtotusec = 1000*7000; + SyncRes::s_maxnsaddressqperq = 10; + SyncRes::s_maxtotusec = 1000 * 7000; SyncRes::s_maxdepth = 40; SyncRes::s_maxnegttl = 3600; SyncRes::s_maxcachettl = 86400; @@ -10229,6 +10230,48 @@ BOOST_AUTO_TEST_CASE(test_getDSRecords_multialgo_prefer_gost_over_sha1) { } #endif // HAVE_BOTAN110 +BOOST_AUTO_TEST_CASE(test_completely_flawed_big_nsset) +{ + std::unique_ptr sr; + initSR(sr); + + primeHints(); + + const DNSName target("powerdns.com."); + size_t queriesCount = 0; + + sr->setAsyncCallback([&queriesCount, target](const ComboAddress& ip, const DNSName& domain, int type, bool doTCP, bool sendRDQuery, int EDNS0Level, struct timeval* now, boost::optional& srcmask, boost::optional context, std::shared_ptr outgoingLogger, LWResult* res, bool* chained) { + queriesCount++; + + if (isRootServer(ip) && domain == target) { + setLWResult(res, 0, false, false, true); + // 20 NS records + for (int i = 0; i < 20; i++) { + string n = string("pdns-public-ns") + std::to_string(i) + string(".powerdns.com."); + addRecordToLW(res, domain, QType::NS, n, DNSResourceRecord::AUTHORITY, 172800); + } + return 1; + } + else if (domain.toString().length() > 14 && domain.toString().substr(0, 14) == "pdns-public-ns") { + setLWResult(res, 0, true, false, true); + addRecordToLW(res, ".", QType::SOA, "a.root-servers.net. nstld.verisign-grs.com. 2017032800 1800 900 604800 86400", DNSResourceRecord::AUTHORITY, 86400); + return 1; + } + return 0; + }); + + vector ret; + try { + sr->beginResolve(target, QType(QType::A), QClass::IN, ret); + BOOST_CHECK(0); + } catch (const ImmediateServFailException& ex) { + BOOST_CHECK_EQUAL(ret.size(), 0U); + // one query to get NSs, then A and AAAA for each NS, 5th NS hits the limit + // limit is reduced to 5, because zone publishes many (20) NS + BOOST_CHECK_EQUAL(queriesCount, 11); + } +} + /* // cerr<<"asyncresolve called to ask "<