File: dnsdist-lua-rules.cc

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/*
 * This file is part of PowerDNS or dnsdist.
 * Copyright -- PowerDNS.COM B.V. and its contributors
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * In addition, for the avoidance of any doubt, permission is granted to
 * link this program with OpenSSL and to (re)distribute the binaries
 * produced as the result of such linking.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
#include "dnsdist.hh"
#include "dnsdist-lua.hh"
#include "dnsdist-rules.hh"
#include "dnsdist-rules-factory.hh"
#include "dnsdist-rule-chains.hh"
#include "dns_random.hh"

std::shared_ptr<DNSRule> makeRule(const luadnsrule_t& var, const std::string& calledFrom)
{
  if (var.type() == typeid(std::shared_ptr<DNSRule>)) {
    return *boost::get<std::shared_ptr<DNSRule>>(&var);
  }

  bool suffixSeen = false;
  SuffixMatchNode smn;
  NetmaskGroup nmg;
  auto add = [&nmg, &smn, &suffixSeen](const string& src) {
    try {
      nmg.addMask(src); // need to try mask first, all masks are domain names!
    }
    catch (...) {
      suffixSeen = true;
      smn.add(DNSName(src));
    }
  };

  if (var.type() == typeid(string)) {
    add(*boost::get<string>(&var));
  }
  else if (var.type() == typeid(LuaArray<std::string>)) {
    for (const auto& str : *boost::get<LuaArray<std::string>>(&var)) {
      add(str.second);
    }
  }
  else if (var.type() == typeid(DNSName)) {
    smn.add(*boost::get<DNSName>(&var));
  }
  else if (var.type() == typeid(LuaArray<DNSName>)) {
    smn = SuffixMatchNode();
    for (const auto& name : *boost::get<LuaArray<DNSName>>(&var)) {
      smn.add(name.second);
    }
  }

  if (nmg.empty()) {
    return std::make_shared<SuffixMatchNodeRule>(smn);
  }
  if (suffixSeen) {
    warnlog("At least one parameter to %s has been parsed as a domain name amongst network masks, and will be ignored!", calledFrom);
  }
  return std::make_shared<NetmaskGroupRule>(nmg, true);
}

static boost::uuids::uuid makeRuleID(std::string& identifier)
{
  if (identifier.empty()) {
    return getUniqueID();
  }

  return getUniqueID(identifier);
}

void parseRuleParams(boost::optional<luaruleparams_t>& params, boost::uuids::uuid& uuid, std::string& name, uint64_t& creationOrder)
{
  static uint64_t s_creationOrder = 0;

  string uuidStr;

  getOptionalValue<std::string>(params, "uuid", uuidStr);
  getOptionalValue<std::string>(params, "name", name);

  uuid = makeRuleID(uuidStr);
  creationOrder = s_creationOrder++;
}

using ruleparams_t = LuaAssociativeTable<boost::variant<bool, int, std::string, LuaArray<int>>>;

template <typename T>
static std::string rulesToString(const std::vector<T>& rules, boost::optional<ruleparams_t>& vars)
{
  int num = 0;
  bool showUUIDs = false;
  size_t truncateRuleWidth = string::npos;
  std::string result;

  getOptionalValue<bool>(vars, "showUUIDs", showUUIDs);
  getOptionalValue<int>(vars, "truncateRuleWidth", truncateRuleWidth);
  checkAllParametersConsumed("rulesToString", vars);

  if (showUUIDs) {
    boost::format fmt("%-3d %-30s %-38s %9d %9d %-56s %s\n");
    result += (fmt % "#" % "Name" % "UUID" % "Cr. Order" % "Matches" % "Rule" % "Action").str();
    for (const auto& lim : rules) {
      string desc = lim.d_rule->toString().substr(0, truncateRuleWidth);
      result += (fmt % num % lim.d_name % boost::uuids::to_string(lim.d_id) % lim.d_creationOrder % lim.d_rule->d_matches % desc % lim.d_action->toString()).str();
      ++num;
    }
  }
  else {
    boost::format fmt("%-3d %-30s %9d %-56s %s\n");
    result += (fmt % "#" % "Name" % "Matches" % "Rule" % "Action").str();
    for (const auto& lim : rules) {
      string desc = lim.d_rule->toString().substr(0, truncateRuleWidth);
      result += (fmt % num % lim.d_name % lim.d_rule->d_matches % desc % lim.d_action->toString()).str();
      ++num;
    }
  }
  return result;
}

template <typename IdentifierT>
static void showRules(IdentifierT identifier, boost::optional<ruleparams_t>& vars)
{
  setLuaNoSideEffect();

  const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
  const auto& rules = dnsdist::rules::getRuleChain(chains, identifier);
  g_outputBuffer += rulesToString(rules, vars);
}

template <typename ChainTypeT, typename RuleTypeT>
static bool removeRuleFromChain(ChainTypeT& rules, const std::function<bool(const RuleTypeT& rule)>& matchFunction)
{
  auto removeIt = std::remove_if(rules.begin(),
                                 rules.end(),
                                 matchFunction);
  if (removeIt == rules.end()) {
    g_outputBuffer = "Error: no rule matched\n";
    return false;
  }
  rules.erase(removeIt,
              rules.end());
  return true;
}

template <typename ChainIdentifierT>
static void rmRule(ChainIdentifierT chainIdentifier, const boost::variant<unsigned int, std::string>& ruleID)
{
  if (const auto* str = boost::get<std::string>(&ruleID)) {
    try {
      const auto uuid = getUniqueID(*str);
      dnsdist::configuration::updateRuntimeConfiguration([chainIdentifier, &uuid](dnsdist::configuration::RuntimeConfiguration& config) {
        constexpr bool isResponseChain = std::is_same_v<ChainIdentifierT, dnsdist::rules::ResponseRuleChain>;
        if constexpr (isResponseChain) {
          auto& rules = dnsdist::rules::getResponseRuleChain(config.d_ruleChains, chainIdentifier);
          std::function<bool(const dnsdist::rules::ResponseRuleAction&)> matchFunction = [&uuid](const dnsdist::rules::ResponseRuleAction& rule) -> bool { return rule.d_id == uuid; };
          removeRuleFromChain(rules, matchFunction);
        }
        else {
          auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chainIdentifier);
          std::function<bool(const dnsdist::rules::RuleAction&)> matchFunction = [&uuid](const dnsdist::rules::RuleAction& rule) -> bool { return rule.d_id == uuid; };
          removeRuleFromChain(rules, matchFunction);
        }
      });
    }
    catch (const std::runtime_error& e) {
      dnsdist::configuration::updateRuntimeConfiguration([chainIdentifier, &str](dnsdist::configuration::RuntimeConfiguration& config) {
        constexpr bool isResponseChain = std::is_same_v<ChainIdentifierT, dnsdist::rules::ResponseRuleChain>;
        if constexpr (isResponseChain) {
          auto& rules = dnsdist::rules::getResponseRuleChain(config.d_ruleChains, chainIdentifier);
          std::function<bool(const dnsdist::rules::ResponseRuleAction&)> matchFunction = [&str](const dnsdist::rules::ResponseRuleAction& rule) -> bool { return rule.d_name == *str; };
          removeRuleFromChain(rules, matchFunction);
        }
        else {
          auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chainIdentifier);
          std::function<bool(const dnsdist::rules::RuleAction&)> matchFunction = [&str](const dnsdist::rules::RuleAction& rule) -> bool { return rule.d_name == *str; };
          removeRuleFromChain(rules, matchFunction);
        }
      });
    }
  }
  else if (const auto* pos = boost::get<unsigned int>(&ruleID)) {
    dnsdist::configuration::updateRuntimeConfiguration([chainIdentifier, pos](dnsdist::configuration::RuntimeConfiguration& config) {
      auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chainIdentifier);
      if (*pos >= rules.size()) {
        g_outputBuffer = "Error: attempt to delete non-existing rule\n";
        return;
      }
      rules.erase(rules.begin() + *pos);
    });
  }
  setLuaSideEffect();
}

template <typename IdentifierTypeT>
static void moveRuleToTop(IdentifierTypeT chainIdentifier)
{
  setLuaSideEffect();
  dnsdist::configuration::updateRuntimeConfiguration([chainIdentifier](dnsdist::configuration::RuntimeConfiguration& config) {
    auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chainIdentifier);
    if (rules.empty()) {
      return;
    }
    // coverity[auto_causes_copy]
    auto subject = *rules.rbegin();
    rules.erase(std::prev(rules.end()));
    rules.insert(rules.begin(), subject);
  });
  setLuaSideEffect();
}

template <typename IdentifierTypeT>
static void mvRule(IdentifierTypeT chainIdentifier, unsigned int from, unsigned int destination)
{
  dnsdist::configuration::updateRuntimeConfiguration([chainIdentifier, from, &destination](dnsdist::configuration::RuntimeConfiguration& config) {
    auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chainIdentifier);
    if (from >= rules.size() || destination > rules.size()) {
      g_outputBuffer = "Error: attempt to move rules from/to invalid index\n";
      return;
    }
    // coverity[auto_causes_copy]
    auto subject = rules[from];
    rules.erase(rules.begin() + from);
    if (destination > rules.size()) {
      rules.push_back(std::move(subject));
    }
    else {
      if (from < destination) {
        --destination;
      }
      rules.insert(rules.begin() + destination, subject);
    }
  });
  setLuaSideEffect();
}

template <typename T>
static std::vector<T> getTopRules(const std::vector<T>& rules, unsigned int top)
{
  std::vector<std::pair<size_t, size_t>> counts;
  counts.reserve(rules.size());

  size_t pos = 0;
  for (const auto& rule : rules) {
    counts.push_back({rule.d_rule->d_matches.load(), pos});
    pos++;
  }

  sort(counts.begin(), counts.end(), [](const decltype(counts)::value_type& lhs, const decltype(counts)::value_type& rhs) {
    return rhs.first < lhs.first;
  });

  std::vector<T> results;
  results.reserve(top);

  size_t count = 0;
  for (const auto& entry : counts) {
    results.emplace_back(rules.at(entry.second));
    ++count;
    if (count == top) {
      break;
    }
  }

  return results;
}

template <typename ActionT, typename IdentifierT>
static void addRule(IdentifierT identifier, const std::string& methodName, const luadnsrule_t& var, const std::shared_ptr<ActionT>& action, boost::optional<luaruleparams_t>& params)
{
  setLuaSideEffect();

  std::string name;
  boost::uuids::uuid uuid{};
  uint64_t creationOrder = 0;
  parseRuleParams(params, uuid, name, creationOrder);
  checkAllParametersConsumed(methodName, params);

  auto rule = makeRule(var, methodName);
  dnsdist::configuration::updateRuntimeConfiguration([identifier, &rule, &action, &name, &uuid, creationOrder](dnsdist::configuration::RuntimeConfiguration& config) {
    dnsdist::rules::add(config.d_ruleChains, identifier, std::move(rule), action, std::move(name), uuid, creationOrder);
  });
}

template <typename T>
static LuaArray<T> toLuaArray(std::vector<T>&& rules)
{
  LuaArray<T> results;
  results.reserve(rules.size());

  size_t pos = 1;
  for (auto& rule : rules) {
    results.emplace_back(pos, std::move(rule));
    pos++;
  }

  return results;
}

template <typename T>
static boost::optional<T> getRuleFromSelector(const std::vector<T>& rules, const boost::variant<unsigned int, std::string>& selector)
{
  if (const auto* str = boost::get<std::string>(&selector)) {
    /* let's see if this a UUID */
    try {
      const auto uuid = getUniqueID(*str);
      for (const auto& rule : rules) {
        if (rule.d_id == uuid) {
          return rule;
        }
      }
    }
    catch (const std::exception& e) {
      /* a name, then */
      for (const auto& rule : rules) {
        if (rule.d_name == *str) {
          return rule;
        }
      }
    }
  }
  else if (const auto* pos = boost::get<unsigned int>(&selector)) {
    /* this will throw a std::out_of_range exception if the
       supplied position is out of bounds, this is fine */
    return rules.at(*pos);
  }
  return boost::none;
}

namespace
{
std::shared_ptr<DNSRule> qnameSuffixRule(const boost::variant<const SuffixMatchNode&, std::string, const LuaArray<std::string>> names, boost::optional<bool> quiet)
{
  if (names.type() == typeid(string)) {
    SuffixMatchNode smn;
    smn.add(DNSName(*boost::get<std::string>(&names)));
    return std::shared_ptr<DNSRule>(new SuffixMatchNodeRule(smn, quiet ? *quiet : false));
  }

  if (names.type() == typeid(LuaArray<std::string>)) {
    SuffixMatchNode smn;
    for (const auto& str : *boost::get<const LuaArray<std::string>>(&names)) {
      smn.add(DNSName(str.second));
    }
    return std::shared_ptr<DNSRule>(new SuffixMatchNodeRule(smn, quiet ? *quiet : false));
  }

  const auto& smn = *boost::get<const SuffixMatchNode&>(&names);
  return std::shared_ptr<DNSRule>(new SuffixMatchNodeRule(smn, quiet ? *quiet : false));
}

template <class T>
std::optional<T> boostToStandardOptional(const boost::optional<T>& boostOpt)
{
  return boostOpt ? *boostOpt : std::optional<T>();
}
}

void setupLuaRuleChainsManagement(LuaContext& luaCtx)
{
  for (const auto& chain : dnsdist::rules::getResponseRuleChainDescriptions()) {
    luaCtx.writeFunction("show" + chain.prefix + "ResponseRules", [&chain](boost::optional<ruleparams_t> vars) {
      showRules(chain.identifier, vars);
    });
    luaCtx.writeFunction("rm" + chain.prefix + "ResponseRule", [&chain](const boost::variant<unsigned int, std::string>& identifier) {
      rmRule(chain.identifier, identifier);
    });
    luaCtx.writeFunction("mv" + chain.prefix + "ResponseRuleToTop", [&chain]() {
      moveRuleToTop(chain.identifier);
    });
    luaCtx.writeFunction("mv" + chain.prefix + "ResponseRule", [&chain](unsigned int from, unsigned int dest) {
      mvRule(chain.identifier, from, dest);
    });
    luaCtx.writeFunction("get" + chain.prefix + "ResponseRule", [&chain](const boost::variant<unsigned int, std::string>& selector) -> boost::optional<dnsdist::rules::ResponseRuleAction> {
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& rules = dnsdist::rules::getResponseRuleChain(chains, chain.identifier);
      return getRuleFromSelector(rules, selector);
    });

    luaCtx.writeFunction("getTop" + chain.prefix + "ResponseRules", [&chain](boost::optional<unsigned int> top) {
      setLuaNoSideEffect();
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& rules = dnsdist::rules::getResponseRuleChain(chains, chain.identifier);
      return toLuaArray(getTopRules(rules, (top ? *top : 10)));
    });

    luaCtx.writeFunction("top" + chain.prefix + "ResponseRules", [&chain](boost::optional<unsigned int> top, boost::optional<ruleparams_t> vars) {
      setLuaNoSideEffect();
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& rules = dnsdist::rules::getResponseRuleChain(chains, chain.identifier);
      return rulesToString(getTopRules(rules, (top ? *top : 10)), vars);
    });

    luaCtx.writeFunction("clear" + chain.prefix + "ResponseRules", [&chain]() {
      setLuaSideEffect();
      dnsdist::configuration::updateRuntimeConfiguration([&chain](dnsdist::configuration::RuntimeConfiguration& config) {
        auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chain.identifier);
        rules.clear();
      });
    });
  }

  for (const auto& chain : dnsdist::rules::getRuleChainDescriptions()) {
    luaCtx.writeFunction("show" + chain.prefix + "Rules", [&chain](boost::optional<ruleparams_t> vars) {
      showRules(chain.identifier, vars);
    });
    luaCtx.writeFunction("rm" + chain.prefix + "Rule", [&chain](const boost::variant<unsigned int, std::string>& identifier) {
      rmRule(chain.identifier, identifier);
    });
    luaCtx.writeFunction("mv" + chain.prefix + "RuleToTop", [&chain]() {
      moveRuleToTop(chain.identifier);
    });
    luaCtx.writeFunction("mv" + chain.prefix + "Rule", [&chain](unsigned int from, unsigned int dest) {
      mvRule(chain.identifier, from, dest);
    });
    luaCtx.writeFunction("get" + chain.prefix + "Rule", [&chain](const boost::variant<int, std::string>& selector) -> boost::optional<dnsdist::rules::RuleAction> {
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& rules = dnsdist::rules::getRuleChain(chains, chain.identifier);
      return getRuleFromSelector(rules, selector);
    });

    luaCtx.writeFunction("getTop" + chain.prefix + "Rules", [&chain](boost::optional<unsigned int> top) {
      setLuaNoSideEffect();
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& rules = dnsdist::rules::getRuleChain(chains, chain.identifier);
      return toLuaArray(getTopRules(rules, (top ? *top : 10)));
    });

    luaCtx.writeFunction("top" + chain.prefix + "Rules", [&chain](boost::optional<unsigned int> top, boost::optional<ruleparams_t> vars) {
      setLuaNoSideEffect();
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& rules = dnsdist::rules::getRuleChain(chains, chain.identifier);

      return rulesToString(getTopRules(rules, (top ? *top : 10)), vars);
    });

    luaCtx.writeFunction("clear" + chain.prefix + "Rules", [&chain]() {
      setLuaSideEffect();
      dnsdist::configuration::updateRuntimeConfiguration([&chain](dnsdist::configuration::RuntimeConfiguration& config) {
        auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chain.identifier);
        rules.clear();
      });
    });

    luaCtx.writeFunction("set" + chain.prefix + "Rules", [&chain](const LuaArray<std::shared_ptr<dnsdist::rules::RuleAction>>& newruleactions) {
      setLuaSideEffect();
      dnsdist::configuration::updateRuntimeConfiguration([&chain, &newruleactions](dnsdist::configuration::RuntimeConfiguration& config) {
        auto& rules = dnsdist::rules::getRuleChain(config.d_ruleChains, chain.identifier);
        rules.clear();
        for (const auto& pair : newruleactions) {
          const auto& newruleaction = pair.second;
          if (newruleaction->d_action) {
            auto rule = newruleaction->d_rule;
            rules.push_back({std::move(rule), newruleaction->d_action, newruleaction->d_name, newruleaction->d_id, newruleaction->d_creationOrder});
          }
        }
      });
    });
  }

  for (const auto& chain : dnsdist::rules::getRuleChainDescriptions()) {
    auto fullName = std::string("add") + chain.prefix + std::string("Action");
    luaCtx.writeFunction(fullName, [&fullName, &chain](const luadnsrule_t& var, boost::variant<std::shared_ptr<DNSAction>, std::shared_ptr<DNSResponseAction>> era, boost::optional<luaruleparams_t> params) {
      if (era.type() != typeid(std::shared_ptr<DNSAction>)) {
        throw std::runtime_error(fullName + "() can only be called with query-related actions, not response-related ones. Are you looking for addResponseAction()?");
      }

      addRule(chain.identifier, fullName, var, boost::get<std::shared_ptr<DNSAction>>(era), params);
    });
    fullName = std::string("get") + chain.prefix + std::string("Action");
    luaCtx.writeFunction(fullName, [&chain](unsigned int num) {
      setLuaNoSideEffect();
      boost::optional<std::shared_ptr<DNSAction>> ret;
      const auto& chains = dnsdist::configuration::getCurrentRuntimeConfiguration().d_ruleChains;
      const auto& ruleactions = dnsdist::rules::getRuleChain(chains, chain.identifier);
      if (num < ruleactions.size()) {
        ret = ruleactions[num].d_action;
      }
      return ret;
    });
  }

  for (const auto& chain : dnsdist::rules::getResponseRuleChainDescriptions()) {
    const auto fullName = std::string("add") + chain.prefix + std::string("ResponseAction");
    luaCtx.writeFunction(fullName, [&fullName, &chain](const luadnsrule_t& var, boost::variant<std::shared_ptr<DNSAction>, std::shared_ptr<DNSResponseAction>> era, boost::optional<luaruleparams_t> params) {
      if (era.type() != typeid(std::shared_ptr<DNSResponseAction>)) {
        throw std::runtime_error(fullName + "() can only be called with response-related actions, not query-related ones. Are you looking for addAction()?");
      }

      addRule(chain.identifier, fullName, var, boost::get<std::shared_ptr<DNSResponseAction>>(era), params);
    });
  }

  luaCtx.writeFunction("benchRule", [](const std::shared_ptr<DNSRule>& rule, boost::optional<unsigned int> times_, boost::optional<string> suffix_) {
    setLuaNoSideEffect();
    unsigned int times = times_ ? *times_ : 100000;
    DNSName suffix(suffix_ ? *suffix_ : "powerdns.com");
    // NOLINTNEXTLINE(bugprone-exception-escape): not sure what clang-tidy smoked, but we do not really care here
    struct item
    {
      PacketBuffer packet;
      InternalQueryState ids;
    };
    vector<item> items;
    items.reserve(1000);
    for (int counter = 0; counter < 1000; ++counter) {
      item entry;
      entry.ids.qname = DNSName(std::to_string(dns_random_uint32()));
      entry.ids.qname += suffix;
      entry.ids.qtype = dns_random(0xff);
      entry.ids.qclass = QClass::IN;
      entry.ids.protocol = dnsdist::Protocol::DoUDP;
      entry.ids.origRemote = ComboAddress("127.0.0.1");
      entry.ids.origRemote.sin4.sin_addr.s_addr = random();
      entry.ids.queryRealTime.start();
      GenericDNSPacketWriter<PacketBuffer> writer(entry.packet, entry.ids.qname, entry.ids.qtype);
      items.push_back(std::move(entry));
    }

    int matches = 0;
    ComboAddress dummy("127.0.0.1");
    StopWatch swatch;
    swatch.start();
    for (unsigned int counter = 0; counter < times; ++counter) {
      item& entry = items[counter % items.size()];
      DNSQuestion dnsQuestion(entry.ids, entry.packet);

      if (rule->matches(&dnsQuestion)) {
        matches++;
      }
    }
    double udiff = swatch.udiff();
    g_outputBuffer = (boost::format("Had %d matches out of %d, %.1f qps, in %.1f us\n") % matches % times % (1000000 * (1.0 * times / udiff)) % udiff).str();
  });
}

// NOLINTNEXTLINE(readability-function-cognitive-complexity): this function declares Lua bindings, even with a good refactoring it will likely blow up the threshold
void setupLuaSelectors(LuaContext& luaCtx)
{
  luaCtx.writeFunction("makeRule", [](const luadnsrule_t& var) -> std::shared_ptr<DNSRule> {
    return makeRule(var, "makeRule");
  });

  luaCtx.registerFunction<string (std::shared_ptr<DNSRule>::*)() const>("toString", [](const std::shared_ptr<DNSRule>& rule) { return rule->toString(); });

  luaCtx.registerFunction<uint64_t (std::shared_ptr<DNSRule>::*)() const>("getMatches", [](const std::shared_ptr<DNSRule>& rule) { return rule->d_matches.load(); });

  luaCtx.registerFunction<std::shared_ptr<DNSRule> (dnsdist::rules::RuleAction::*)() const>("getSelector", [](const dnsdist::rules::RuleAction& rule) { return rule.d_rule; });

  luaCtx.registerFunction<std::shared_ptr<DNSAction> (dnsdist::rules::RuleAction::*)() const>("getAction", [](const dnsdist::rules::RuleAction& rule) { return rule.d_action; });

  luaCtx.registerFunction<std::shared_ptr<DNSRule> (dnsdist::rules::ResponseRuleAction::*)() const>("getSelector", [](const dnsdist::rules::ResponseRuleAction& rule) { return rule.d_rule; });

  luaCtx.registerFunction<std::shared_ptr<DNSResponseAction> (dnsdist::rules::ResponseRuleAction::*)() const>("getAction", [](const dnsdist::rules::ResponseRuleAction& rule) { return rule.d_action; });

  luaCtx.writeFunction("SuffixMatchNodeRule", qnameSuffixRule);

  luaCtx.writeFunction("NetmaskGroupRule", [](const boost::variant<const NetmaskGroup&, std::string, const LuaArray<std::string>> netmasks, boost::optional<bool> src, boost::optional<bool> quiet) {
    if (netmasks.type() == typeid(string)) {
      NetmaskGroup nmg;
      nmg.addMask(*boost::get<std::string>(&netmasks));
      return std::shared_ptr<DNSRule>(new NetmaskGroupRule(nmg, src ? *src : true, quiet ? *quiet : false));
    }

    if (netmasks.type() == typeid(LuaArray<std::string>)) {
      NetmaskGroup nmg;
      for (const auto& str : *boost::get<const LuaArray<std::string>>(&netmasks)) {
        nmg.addMask(str.second);
      }
      return std::shared_ptr<DNSRule>(new NetmaskGroupRule(nmg, src ? *src : true, quiet ? *quiet : false));
    }

    const auto& nmg = *boost::get<const NetmaskGroup&>(&netmasks);
    return std::shared_ptr<DNSRule>(new NetmaskGroupRule(nmg, src ? *src : true, quiet ? *quiet : false));
  });

  luaCtx.writeFunction("QNameSuffixRule", qnameSuffixRule);

  luaCtx.writeFunction("QTypeRule", [](boost::variant<unsigned int, std::string> str) {
    uint16_t qtype{};
    if (const auto* dir = boost::get<unsigned int>(&str)) {
      qtype = *dir;
    }
    else {
      string val = boost::get<string>(str);
      qtype = QType::chartocode(val.c_str());
      if (qtype == 0) {
        throw std::runtime_error("Unable to convert '" + val + "' to a DNS type");
      }
    }
    return std::shared_ptr<DNSRule>(new QTypeRule(qtype));
  });

  luaCtx.writeFunction("QClassRule", [](uint64_t cla) {
    checkParameterBound("QClassRule", cla, std::numeric_limits<uint16_t>::max());
    return std::shared_ptr<DNSRule>(new QClassRule(cla));
  });

  luaCtx.writeFunction("AndRule", [](const LuaArray<std::shared_ptr<DNSRule>>& rulePairs) {
    std::vector<std::shared_ptr<DNSRule>> rules;
    rules.reserve(rulePairs.size());
    for (const auto& pair : rulePairs) {
      rules.emplace_back(pair.second);
    }
    return std::shared_ptr<DNSRule>(new AndRule(rules));
  });

  luaCtx.writeFunction("OrRule", [](const LuaArray<std::shared_ptr<DNSRule>>& rulePairs) {
    std::vector<std::shared_ptr<DNSRule>> rules;
    rules.reserve(rulePairs.size());
    for (const auto& pair : rulePairs) {
      rules.emplace_back(pair.second);
    }
    return std::shared_ptr<DNSRule>(new OrRule(rules));
  });

  luaCtx.writeFunction("NotRule", [](const std::shared_ptr<DNSRule>& rule) {
    return std::shared_ptr<DNSRule>(new NotRule(rule));
  });

  luaCtx.writeFunction("LuaRule", [](const dnsdist::selectors::LuaSelectorFunction& function) {
    return std::shared_ptr<DNSRule>(dnsdist::selectors::getLuaSelector(function));
  });

  luaCtx.writeFunction("LuaFFIRule", [](const dnsdist::selectors::LuaSelectorFFIFunction& function) {
    return std::shared_ptr<DNSRule>(dnsdist::selectors::getLuaFFISelector(function));
  });

  luaCtx.writeFunction("RCodeRule", [](uint64_t rcode) {
    checkParameterBound("RCodeRule", rcode, std::numeric_limits<uint8_t>::max());
    return std::shared_ptr<DNSRule>(new RCodeRule(rcode));
  });

  luaCtx.writeFunction("ERCodeRule", [](uint64_t rcode) {
    checkParameterBound("ERCodeRule", rcode, std::numeric_limits<uint8_t>::max());
    return std::shared_ptr<DNSRule>(new ERCodeRule(rcode));
  });

  luaCtx.writeFunction("TimedIPSetRule", []() {
    return std::make_shared<TimedIPSetRule>();
  });

  luaCtx.registerFunction<void (std::shared_ptr<TimedIPSetRule>::*)()>("clear", [](const std::shared_ptr<TimedIPSetRule>& tisr) {
    tisr->clear();
  });

  luaCtx.registerFunction<void (std::shared_ptr<TimedIPSetRule>::*)()>("cleanup", [](const std::shared_ptr<TimedIPSetRule>& tisr) {
    tisr->cleanup();
  });

  luaCtx.registerFunction<void (std::shared_ptr<TimedIPSetRule>::*)(const ComboAddress&, int)>("add", [](const std::shared_ptr<TimedIPSetRule>& tisr, const ComboAddress& addr, int additional) {
    tisr->add(addr, time(nullptr) + additional);
  });

  luaCtx.registerFunction<std::shared_ptr<DNSRule> (std::shared_ptr<TimedIPSetRule>::*)()>("slice", [](const std::shared_ptr<TimedIPSetRule>& tisr) {
    return std::dynamic_pointer_cast<DNSRule>(tisr);
  });
  luaCtx.registerFunction<void (std::shared_ptr<TimedIPSetRule>::*)()>("__tostring", [](const std::shared_ptr<TimedIPSetRule>& tisr) {
    tisr->toString();
  });

  luaCtx.writeFunction("QNameRule", [](const std::string& qname) {
    return std::shared_ptr<DNSRule>(dnsdist::selectors::getQNameSelector(DNSName(qname)));
  });

  luaCtx.writeFunction("QNameSetRule", [](const DNSNameSet& names) {
    return std::shared_ptr<DNSRule>(new QNameSetRule(names));
  });

  // NOLINTNEXTLINE(performance-unnecessary-value-param): LuaWrapper does not play well with const boost::optional<T>&
  luaCtx.writeFunction("TagRule", [](const std::string& tag, boost::optional<std::string> value) {
    return std::shared_ptr<DNSRule>(dnsdist::selectors::getTagSelector(tag, boostToStandardOptional(value), !value));
  });

#if defined(HAVE_LMDB) || defined(HAVE_CDB)
  luaCtx.writeFunction("KeyValueStoreLookupRule", [](std::shared_ptr<KeyValueStore>& kvs, std::shared_ptr<KeyValueLookupKey>& lookupKey) {
    return std::shared_ptr<DNSRule>(new KeyValueStoreLookupRule(kvs, lookupKey));
  });

  luaCtx.writeFunction("KeyValueStoreRangeLookupRule", [](std::shared_ptr<KeyValueStore>& kvs, std::shared_ptr<KeyValueLookupKey>& lookupKey) {
    return std::shared_ptr<DNSRule>(new KeyValueStoreRangeLookupRule(kvs, lookupKey));
  });
#endif /* defined(HAVE_LMDB) || defined(HAVE_CDB) */

#include "dnsdist-lua-selectors-generated-body.hh"
}