pdns/dnsdist-ecs.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 // root label (1), type (2), class (2), ttl (4) + rdlen (2)
  25 static const size_t optRecordMinimumSize = 11;
  26
  27 extern size_t g_EdnsUDPPayloadSize;
  28 extern uint16_t g_PayloadSizeSelfGenAnswers;
  29
  30 int rewriteResponseWithoutEDNS(const std::string& initialPacket, vector<uint8_t>& newContent);
  31 int locateEDNSOptRR(const std::string& packet, uint16_t * optStart, size_t * optLen, bool * last);
  32 void generateOptRR(const std::string& optRData, string& res, uint16_t udpPayloadSize, uint8_t ednsrcode, bool dnssecOK);
  33 void generateECSOption(const ComboAddress& source, string& res, uint16_t ECSPrefixLength);
  34 int removeEDNSOptionFromOPT(char* optStart, size_t* optLen, const uint16_t optionCodeToRemove);
  35 int rewriteResponseWithoutEDNSOption(const std::string& initialPacket, const uint16_t optionCodeToSkip, vector<uint8_t>& newContent);
  36 int getEDNSOptionsStart(const char* packet, const size_t offset, const size_t len, uint16_t* optRDPosition, size_t * remaining);
  37 bool isEDNSOptionInOpt(const std::string& packet, const size_t optStart, const size_t optLen, const uint16_t optionCodeToFind, size_t* optContentStart = nullptr, uint16_t* optContentLen = nullptr);
  38 bool addEDNS(dnsheader* dh, uint16_t& len, const size_t size, bool dnssecOK, uint16_t payloadSize, uint8_t ednsrcode);
  39 bool addEDNSToQueryTurnedResponse(DNSQuestion& dq);
  40
  41 bool handleEDNSClientSubnet(DNSQuestion& dq, bool& ednsAdded, bool& ecsAdded, bool preserveTrailingData);
  42 bool handleEDNSClientSubnet(char* packet, size_t packetSize, unsigned int consumed, uint16_t* len, bool& ednsAdded, bool& ecsAdded, bool overrideExisting, const string& newECSOption, bool preserveTrailingData);
  43
  44 bool parseEDNSOptions(DNSQuestion& dq);
  45
  46 int getEDNSZ(const DNSQuestion& dq);
  47 bool queryHasEDNS(const DNSQuestion& dq);
  48 bool getEDNS0Record(const DNSQuestion& dq, EDNS0Record& edns0);