pdns/ueberbackend.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 UEBERBACKEND_HH
  23 #define UEBERBACKEND_HH
  24
  25 #include <vector>
  26 #include <map>
  27 #include <string>
  28 #include <algorithm>
  29 #include <pthread.h>
  30 #include <semaphore.h>
  31
  32 #include <unistd.h>
  33 #include <sys/stat.h>
  34 #include <fcntl.h>
  35 #include <unistd.h>
  36 #include <boost/utility.hpp>
  37 #include "dnspacket.hh"
  38 #include "dnsbackend.hh"
  39
  40 #include "namespaces.hh"
  41
  42 /** This is a very magic backend that allows us to load modules dynamically,
  43     and query them in order. This is persistent over all UeberBackend instantiations
  44     across multiple threads.
  45
  46     The UeberBackend is transparent for exceptions, which should fall straight through.
  47 */
  48
  49 class UeberBackend : public boost::noncopyable
  50 {
  51 public:
  52   UeberBackend(const string &pname="default");
  53   ~UeberBackend();
  54
  55   bool superMasterBackend(const string &ip, const DNSName &domain, const vector<DNSResourceRecord>&nsset, string *nameserver, string *account, DNSBackend **db);
  56
  57   /** Tracks all created UeberBackend instances for us. We use this vector to notify
  58       existing threads of new modules
  59   */
  60   static vector<UeberBackend *>instances;
  61   static pthread_mutex_t instances_lock;
  62
  63   static bool loadmodule(const string &name);
  64   static bool loadModules(const vector<string>& modules, const string& path);
  65
  66   static void go(void);
  67
  68   /** This contains all registered backends. The DynListener modifies this list for us when
  69       new modules are loaded */
  70   vector<DNSBackend*> backends;
  71
  72   void cleanup();
  73
  74   //! the very magic handle for UeberBackend questions
  75   class handle
  76   {
  77   public:
  78     bool get(DNSZoneRecord &dr);
  79     handle();
  80     ~handle();
  81
  82     //! The UeberBackend class where this handle belongs to
  83     UeberBackend *parent;
  84     //! The current real backend, which is answering questions
  85     DNSBackend *d_hinterBackend;
  86
  87     //! DNSPacket who asked this question
  88     DNSPacket *pkt_p;
  89     DNSName qname;
  90
  91     //! Index of the current backend within the backends vector
  92     unsigned int i;
  93     QType qtype;
  94
  95   private:
  96
  97     static AtomicCounter instances;
  98   };
  99
 100   void lookup(const QType &, const DNSName &qdomain, DNSPacket *pkt_p=0,  int zoneId=-1);
 101
 102   /** Determines if we are authoritative for a zone, and at what level */
 103   bool getAuth(const DNSName &target, const QType &qtype, SOAData* sd, bool cachedOk=true);
 104   bool getSOA(const DNSName &domain, SOAData &sd);
 105   /** Load SOA info from backends, ignoring the cache.*/
 106   bool getSOAUncached(const DNSName &domain, SOAData &sd);
 107   bool get(DNSZoneRecord &r);
 108   void getAllDomains(vector<DomainInfo> *domains, bool include_disabled=false);
 109
 110   void getUnfreshSlaveInfos(vector<DomainInfo>* domains);
 111   void getUpdatedMasters(vector<DomainInfo>* domains);
 112   bool getDomainInfo(const DNSName &domain, DomainInfo &di, bool getSerial=true);
 113   bool createDomain(const DNSName &domain);
 114
 115   bool doesDNSSEC();
 116   bool addDomainKey(const DNSName& name, const DNSBackend::KeyData& key, int64_t& id);
 117   bool getDomainKeys(const DNSName& name, std::vector<DNSBackend::KeyData>& keys);
 118   bool getAllDomainMetadata(const DNSName& name, std::map<std::string, std::vector<std::string> >& meta);
 119   bool getDomainMetadata(const DNSName& name, const std::string& kind, std::vector<std::string>& meta);
 120   bool setDomainMetadata(const DNSName& name, const std::string& kind, const std::vector<std::string>& meta);
 121
 122   bool removeDomainKey(const DNSName& name, unsigned int id);
 123   bool activateDomainKey(const DNSName& name, unsigned int id);
 124   bool deactivateDomainKey(const DNSName& name, unsigned int id);
 125
 126   bool getTSIGKey(const DNSName& name, DNSName* algorithm, string* content);
 127   bool setTSIGKey(const DNSName& name, const DNSName& algorithm, const string& content);
 128   bool deleteTSIGKey(const DNSName& name);
 129   bool getTSIGKeys(std::vector< struct TSIGKey > &keys);
 130
 131   void alsoNotifies(const DNSName &domain, set<string> *ips);
 132   void rediscover(string* status=0);
 133   void reload();
 134   bool searchRecords(const string &pattern, int maxResults, vector<DNSResourceRecord>& result);
 135   bool searchComments(const string &pattern, int maxResults, vector<Comment>& result);
 136 private:
 137   pthread_t d_tid;
 138   handle d_handle;
 139   vector<DNSZoneRecord> d_answers;
 140   vector<DNSZoneRecord>::const_iterator d_cachehandleiter;
 141
 142   static pthread_mutex_t d_mut;
 143   static pthread_cond_t d_cond;
 144
 145   struct Question
 146   {
 147     DNSName qname;
 148     int zoneId;
 149     QType qtype;
 150   }d_question;
 151
 152   unsigned int d_cache_ttl, d_negcache_ttl;
 153   int d_domain_id;
 154   int d_ancount;
 155
 156   bool d_negcached;
 157   bool d_cached;
 158   static bool d_go;
 159   bool d_stale;
 160
 161   int cacheHas(const Question &q, vector<DNSZoneRecord> &rrs);
 162   void addNegCache(const Question &q);
 163   void addCache(const Question &q, const vector<DNSZoneRecord> &rrs);
 164
 165 };
 166
 167 #endif