pdns/lua-recursor4.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
  24 #ifdef HAVE_CONFIG_H
  25 #include "config.h"
  26 #endif
  27
  28 #include "iputils.hh"
  29 #include "dnsname.hh"
  30 #include "namespaces.hh"
  31 #include "dnsrecords.hh"
  32 #include "filterpo.hh"
  33 #include "ednsoptions.hh"
  34 #include "validate.hh"
  35 #include "lua-base4.hh"
  36 #include <unordered_map>
  37
  38 #include "lua-recursor4-ffi.hh"
  39
  40 string GenUDPQueryResponse(const ComboAddress& dest, const string& query);
  41 unsigned int getRecursorThreadId();
  42
  43 // pdns_ffi_param_t is a lightuserdata
  44 template<>
  45 struct LuaContext::Pusher<pdns_ffi_param*> {
  46     static const int minSize = 1;
  47     static const int maxSize = 1;
  48
  49     static PushedObject push(lua_State* state, pdns_ffi_param* ptr) noexcept {
  50         lua_pushlightuserdata(state, ptr);
  51         return PushedObject{state, 1};
  52     }
  53 };
  54
  55 class RecursorLua4 : public BaseLua4
  56 {
  57 public:
  58   RecursorLua4();
  59   ~RecursorLua4(); // this is so unique_ptr works with an incomplete type
  60
  61   struct DNSQuestion
  62   {
  63     DNSQuestion(const ComboAddress& rem, const ComboAddress& loc, const DNSName& query, uint16_t type, bool tcp, bool& variable_, bool& wantsRPZ_, bool& logResponse_): qname(query), qtype(type), local(loc), remote(rem), isTcp(tcp), variable(variable_), wantsRPZ(wantsRPZ_), logResponse(logResponse_)
  64     {
  65     }
  66     const DNSName& qname;
  67     const uint16_t qtype;
  68     const ComboAddress& local;
  69     const ComboAddress& remote;
  70     const struct dnsheader* dh{nullptr};
  71     const bool isTcp;
  72     const std::vector<pair<uint16_t, string>>* ednsOptions{nullptr};
  73     const uint16_t* ednsFlags{nullptr};
  74     vector<DNSRecord>* currentRecords{nullptr};
  75     DNSFilterEngine::Policy* appliedPolicy{nullptr};
  76     std::vector<std::string>* policyTags{nullptr};
  77     std::unordered_map<std::string,bool>* discardedPolicies{nullptr};
  78     std::string requestorId;
  79     std::string deviceId;
  80     vState validationState{Indeterminate};
  81     bool& variable;
  82     bool& wantsRPZ;
  83     bool& logResponse;
  84     unsigned int tag{0};
  85
  86     void addAnswer(uint16_t type, const std::string& content, boost::optional<int> ttl, boost::optional<string> name);
  87     void addRecord(uint16_t type, const std::string& content, DNSResourceRecord::Place place, boost::optional<int> ttl, boost::optional<string> name);
  88     vector<pair<int,DNSRecord> > getRecords() const;
  89     boost::optional<dnsheader> getDH() const;
  90     vector<pair<uint16_t, string> > getEDNSOptions() const;
  91     boost::optional<string> getEDNSOption(uint16_t code) const;
  92     boost::optional<Netmask> getEDNSSubnet() const;
  93     vector<string> getEDNSFlags() const;
  94     bool getEDNSFlag(string flag) const;
  95     void setRecords(const vector<pair<int,DNSRecord> >& records);
  96
  97     int rcode{0};
  98     // struct dnsheader, packet length would be great
  99     vector<DNSRecord> records;
 100
 101     string followupFunction;
 102     string followupPrefix;
 103
 104     string udpQuery;
 105     ComboAddress udpQueryDest;
 106     string udpAnswer;
 107     string udpCallback;
 108
 109     LuaContext::LuaObject data;
 110     DNSName followupName;
 111   };
 112
 113   unsigned int gettag(const ComboAddress& remote, const Netmask& ednssubnet, const ComboAddress& local, const DNSName& qname, uint16_t qtype, std::vector<std::string>* policyTags, LuaContext::LuaObject& data, const EDNSOptionViewMap&, bool tcp, std::string& requestorId, std::string& deviceId) const;
 114   unsigned int gettag_ffi(const ComboAddress& remote, const Netmask& ednssubnet, const ComboAddress& local, const DNSName& qname, uint16_t qtype, std::vector<std::string>* policyTags, LuaContext::LuaObject& data, const EDNSOptionViewMap&, bool tcp, std::string& requestorId, std::string& deviceId, uint32_t& ttlCap, bool& variable, bool& logQuery) const;
 115
 116   void maintenance() const;
 117   bool prerpz(DNSQuestion& dq, int& ret) const;
 118   bool preresolve(DNSQuestion& dq, int& ret) const;
 119   bool nxdomain(DNSQuestion& dq, int& ret) const;
 120   bool nodata(DNSQuestion& dq, int& ret) const ;
 121   bool postresolve(DNSQuestion& dq, int& ret) const;
 122
 123   bool preoutquery(const ComboAddress& ns, const ComboAddress& requestor, const DNSName& query, const QType& qtype, bool isTcp, vector<DNSRecord>& res, int& ret) const;
 124   bool ipfilter(const ComboAddress& remote, const ComboAddress& local, const struct dnsheader&) const;
 125
 126   bool needDQ() const
 127   {
 128     return (d_prerpz ||
 129             d_preresolve ||
 130             d_nxdomain ||
 131             d_nodata ||
 132             d_postresolve);
 133   }
 134
 135   typedef std::function<std::tuple<unsigned int,boost::optional<std::unordered_map<int,string> >,boost::optional<LuaContext::LuaObject>,boost::optional<std::string>,boost::optional<std::string> >(ComboAddress, Netmask, ComboAddress, DNSName, uint16_t, const EDNSOptionViewMap&, bool)> gettag_t;
 136   gettag_t d_gettag; // public so you can query if we have this hooked
 137   typedef std::function<boost::optional<LuaContext::LuaObject>(pdns_ffi_param_t*)> gettag_ffi_t;
 138   gettag_ffi_t d_gettag_ffi;
 139
 140 protected:
 141   virtual void postPrepareContext() override;
 142   virtual void postLoad() override;
 143 private:
 144   typedef std::function<void()> luamaintenance_t;
 145   luamaintenance_t d_maintenance;
 146   typedef std::function<bool(DNSQuestion*)> luacall_t;
 147   luacall_t d_prerpz, d_preresolve, d_nxdomain, d_nodata, d_postresolve, d_preoutquery, d_postoutquery;
 148   bool genhook(const luacall_t& func, DNSQuestion& dq, int& ret) const;
 149   typedef std::function<bool(ComboAddress,ComboAddress, struct dnsheader)> ipfilter_t;
 150   ipfilter_t d_ipfilter;
 151 };
 152