pdns/recpacketcache.hh

   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 #ifndef PDNS_RECPACKETCACHE_HH
  23 #define PDNS_RECPACKETCACHE_HH
  24 #include <string>
  25 #include <inttypes.h>
  26 #include "dns.hh"
  27 #include "namespaces.hh"
  28 #include <iostream>
  29 #include <boost/multi_index_container.hpp>
  30 #include <boost/multi_index/ordered_index.hpp>
  31 #include <boost/multi_index/hashed_index.hpp>
  32 #include <boost/tuple/tuple_comparison.hpp>
  33 #include <boost/multi_index/sequenced_index.hpp>
  34
  35 #include "packetcache.hh"
  36 #include "validate.hh"
  37
  38 #ifdef HAVE_CONFIG_H
  39 #include "config.h"
  40 #endif
  41 #include "rec-protobuf.hh"
  42
  43
  44 using namespace ::boost::multi_index;
  45
  46 //! Stores whole packets, ready for lobbing back at the client. Not threadsafe.
  47 /* Note: we store answers as value AND KEY, and with careful work, we make sure that
  48    you can use a query as a key too. But query and answer must compare as identical!
  49
  50    This precludes doing anything smart with EDNS directly from the packet */
  51 class RecursorPacketCache: public PacketCache
  52 {
  53 public:
  54   RecursorPacketCache();
  55   bool getResponsePacket(unsigned int tag, const std::string& queryPacket, time_t now, std::string* responsePacket, uint32_t* age, uint32_t* qhash);
  56   bool getResponsePacket(unsigned int tag, const std::string& queryPacket, const DNSName& qname, uint16_t qtype, uint16_t qclass, time_t now, std::string* responsePacket, uint32_t* age, uint32_t* qhash);
  57   bool getResponsePacket(unsigned int tag, const std::string& queryPacket, const DNSName& qname, uint16_t qtype, uint16_t qclass, time_t now, std::string* responsePacket, uint32_t* age, vState* valState, uint32_t* qhash, uint16_t* ecsBegin, uint16_t* ecsEnd, RecProtoBufMessage* protobufMessage);
  58   bool getResponsePacket(unsigned int tag, const std::string& queryPacket, DNSName& qname, uint16_t* qtype, uint16_t* qclass, time_t now, std::string* responsePacket, uint32_t* age, vState* valState, uint32_t* qhash, uint16_t* ecsBegin, uint16_t* ecsEnd, RecProtoBufMessage* protobufMessage);
  59   void insertResponsePacket(unsigned int tag, uint32_t qhash, std::string&& query, const DNSName& qname, uint16_t qtype, uint16_t qclass, std::string&& responsePacket, time_t now, uint32_t ttl, const vState& valState, uint16_t ecsBegin, uint16_t ecsEnd, boost::optional<RecProtoBufMessage>&& protobufMessage);
  60   void doPruneTo(unsigned int maxSize=250000);
  61   uint64_t doDump(int fd);
  62   int doWipePacketCache(const DNSName& name, uint16_t qtype=0xffff, bool subtree=false);
  63
  64   void prune();
  65   uint64_t d_hits, d_misses;
  66   uint64_t size();
  67   uint64_t bytes();
  68
  69 private:
  70   struct HashTag {};
  71   struct NameTag {};
  72   struct Entry
  73   {
  74     Entry(const DNSName& qname, std::string&& packet, std::string&& query): d_name(qname), d_packet(std::move(packet)), d_query(std::move(query))
  75     {
  76     }
  77
  78     DNSName d_name;
  79     mutable std::string d_packet; // "I know what I am doing"
  80     mutable std::string d_query;
  81 #ifdef HAVE_PROTOBUF
  82     mutable boost::optional<RecProtoBufMessage> d_protobufMessage;
  83 #endif
  84     mutable time_t d_ttd;
  85     mutable time_t d_creation; // so we can 'age' our packets
  86     uint32_t d_qhash;
  87     uint32_t d_tag;
  88     uint16_t d_type;
  89     uint16_t d_class;
  90     mutable uint16_t d_ecsBegin;
  91     mutable uint16_t d_ecsEnd;
  92     mutable vState d_vstate;
  93     inline bool operator<(const struct Entry& rhs) const;
  94
  95     time_t getTTD() const
  96     {
  97       return d_ttd;
  98     }
  99   };
 100
 101   typedef multi_index_container<
 102     Entry,
 103     indexed_by  <
 104       hashed_non_unique<tag<HashTag>, composite_key<Entry, member<Entry,uint32_t,&Entry::d_tag>, member<Entry,uint32_t,&Entry::d_qhash> > >,
 105       sequenced<> ,
 106       ordered_non_unique<tag<NameTag>, member<Entry,DNSName,&Entry::d_name>, CanonDNSNameCompare >
 107       >
 108   > packetCache_t;
 109
 110   packetCache_t d_packetCache;
 111
 112   static bool qrMatch(const packetCache_t::index<HashTag>::type::iterator& iter, const std::string& queryPacket, const DNSName& qname, uint16_t qtype, uint16_t qclass, uint16_t ecsBegin, uint16_t ecsEnd);
 113   bool checkResponseMatches(std::pair<packetCache_t::index<HashTag>::type::iterator, packetCache_t::index<HashTag>::type::iterator> range, const std::string& queryPacket, const DNSName& qname, uint16_t qtype, uint16_t qclass, time_t now, std::string* responsePacket, uint32_t* age, vState* valState, RecProtoBufMessage* protobufMessage, uint16_t ecsBegin, uint16_t ecsEnd);
 114
 115 public:
 116   void preRemoval(const Entry& entry)
 117   {
 118   }
 119 };
 120
 121 #endif