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