pdns/recursordist/rec-protozero.cc

   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
  23 #include "dnsrecords.hh"
  24 #include "rec-protozero.hh"
  25 #include <variant>
  26
  27 void pdns::ProtoZero::RecMessage::addRR(const DNSRecord& record, const std::set<uint16_t>& exportTypes, [[maybe_unused]] bool udr)
  28 {
  29   if (record.d_place != DNSResourceRecord::ANSWER || record.d_class != QClass::IN) {
  30     return;
  31   }
  32
  33   if (exportTypes.count(record.d_type) == 0) {
  34     return;
  35   }
  36
  37   protozero::pbf_writer pbf_rr{d_response, static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::ResponseField::rrs)};
  38
  39   encodeDNSName(pbf_rr, d_rspbuf, static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::name), record.d_name);
  40   pbf_rr.add_uint32(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::type), record.d_type);
  41   pbf_rr.add_uint32(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::class_), record.d_class);
  42   pbf_rr.add_uint32(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::ttl), record.d_ttl);
  43
  44   auto add = [&](const std::string& str) {
  45     if (size() + str.length() < std::numeric_limits<uint16_t>::max() / 2) {
  46       pbf_rr.add_string(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::rdata), str);
  47     }
  48   };
  49
  50   switch (record.d_type) {
  51   case QType::A: {
  52     const auto& content = getRR<ARecordContent>(record);
  53     if (!content) {
  54       return;
  55     }
  56     ComboAddress data = content->getCA();
  57     pbf_rr.add_bytes(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::rdata), reinterpret_cast<const char*>(&data.sin4.sin_addr.s_addr), sizeof(data.sin4.sin_addr.s_addr));
  58     break;
  59   }
  60   case QType::AAAA: {
  61     const auto& content = getRR<AAAARecordContent>(record);
  62     if (!content) {
  63       return;
  64     }
  65     ComboAddress data = content->getCA();
  66     pbf_rr.add_bytes(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::rdata), reinterpret_cast<const char*>(&data.sin6.sin6_addr.s6_addr), sizeof(data.sin6.sin6_addr.s6_addr));
  67     break;
  68   }
  69   case QType::CNAME: {
  70     const auto& content = getRR<CNAMERecordContent>(record);
  71     if (!content) {
  72       return;
  73     }
  74     add(content->getTarget().toString());
  75     break;
  76   }
  77   case QType::TXT: {
  78     const auto& content = getRR<TXTRecordContent>(record);
  79     if (!content) {
  80       return;
  81     }
  82     add(content->d_text);
  83     break;
  84   }
  85   case QType::NS: {
  86     const auto& content = getRR<NSRecordContent>(record);
  87     if (!content) {
  88       return;
  89     }
  90     add(content->getNS().toString());
  91     break;
  92   }
  93   case QType::PTR: {
  94     const auto& content = getRR<PTRRecordContent>(record);
  95     if (!content) {
  96       return;
  97     }
  98     add(content->getContent().toString());
  99     break;
 100   }
 101   case QType::MX: {
 102     const auto& content = getRR<MXRecordContent>(record);
 103     if (!content) {
 104       return;
 105     }
 106     add(content->d_mxname.toString());
 107     break;
 108   }
 109   case QType::SPF: {
 110     const auto& content = getRR<SPFRecordContent>(record);
 111     if (!content) {
 112       return;
 113     }
 114     add(content->getText());
 115     break;
 116   }
 117   case QType::SRV: {
 118     const auto& content = getRR<SRVRecordContent>(record);
 119     if (!content) {
 120       return;
 121     }
 122     add(content->d_target.toString());
 123     break;
 124   }
 125   default:
 126     break;
 127   }
 128 #ifdef NOD_ENABLED
 129   pbf_rr.add_bool(static_cast<protozero::pbf_tag_type>(pdns::ProtoZero::Message::RRField::udr), udr);
 130   pbf_rr.commit();
 131
 132   // Save the offset of the byte containing the just added bool. We can do this since
 133   // we know a bit about how protobuf's encoding works.
 134   offsets.push_back(d_rspbuf.length() - 1);
 135 #endif
 136 }
 137
 138 #ifdef NOD_ENABLED
 139 void pdns::ProtoZero::RecMessage::clearUDR(std::string& str)
 140 {
 141   for (auto i : offsets) {
 142     str.at(i) = 0;
 143   }
 144 }
 145 #endif
 146
 147 void pdns::ProtoZero::RecMessage::addEvents(const RecEventTrace& trace)
 148 {
 149   for (const auto& t : trace.getEvents()) {
 150     protozero::pbf_writer pbf_trace{d_message, static_cast<protozero::pbf_tag_type>(Field::trace)};
 151     pbf_trace.add_int64(static_cast<protozero::pbf_tag_type>(Event::ts), t.d_ts);
 152     pbf_trace.add_uint32(static_cast<protozero::pbf_tag_type>(Event::event), t.d_event);
 153     pbf_trace.add_bool(static_cast<protozero::pbf_tag_type>(Event::start), t.d_start);
 154
 155     const auto& v = t.d_value;
 156     if (std::holds_alternative<std::nullopt_t>(v)) {
 157     }
 158     else if (std::holds_alternative<bool>(v)) {
 159       pbf_trace.add_bool(static_cast<protozero::pbf_tag_type>(Event::boolVal), std::get<bool>(v));
 160     }
 161     else if (std::holds_alternative<int64_t>(v)) {
 162       pbf_trace.add_int64(static_cast<protozero::pbf_tag_type>(Event::intVal), std::get<int64_t>(v));
 163     }
 164     else if (std::holds_alternative<std::string>(v)) {
 165       pbf_trace.add_string(static_cast<protozero::pbf_tag_type>(Event::stringVal), std::get<std::string>(v));
 166     }
 167     else if (std::holds_alternative<PacketBuffer>(v)) {
 168       const PacketBuffer& p = std::get<PacketBuffer>(v);
 169       pbf_trace.add_bytes(static_cast<protozero::pbf_tag_type>(Event::bytesVal), reinterpret_cast<const char*>(p.data()), p.size());
 170     }
 171     if (!t.d_custom.empty()) {
 172       pbf_trace.add_string(static_cast<protozero::pbf_tag_type>(Event::custom), t.d_custom);
 173     }
 174   }
 175 }