lokinet/llarp/dns/question.cpp

#include "question.hpp"

#include <llarp/util/logging.hpp>
#include <llarp/util/str.hpp>
#include "dns.hpp"

namespace llarp
{
  namespace dns
  {
    static auto logcat = log::Cat("dns");

    Question::Question(Question&& other)
        : qname(std::move(other.qname))
        , qtype(std::move(other.qtype))
        , qclass(std::move(other.qclass))
    {}
    Question::Question(const Question& other)
        : qname(other.qname), qtype(other.qtype), qclass(other.qclass)
    {}

    Question::Question(std::string name, QType_t type)
        : qname{std::move(name)}, qtype{type}, qclass{qClassIN}
    {
      if (qname.empty())
        throw std::invalid_argument{"qname cannot be empty"};
    }

    bool
    Question::Encode(llarp_buffer_t* buf) const
    {
      if (!EncodeNameTo(buf, qname))
        return false;
      if (!buf->put_uint16(qtype))
        return false;
      return buf->put_uint16(qclass);
    }

    bool
    Question::Decode(llarp_buffer_t* buf)
    {
      if (auto name = DecodeName(buf))
        qname = *std::move(name);
      else
      {
        log::error(logcat, "failed to decode name");
        return false;
      }
      if (!buf->read_uint16(qtype))
      {
        log::error(logcat, "failed to decode type");
        return false;
      }
      if (!buf->read_uint16(qclass))
      {
        log::error(logcat, "failed to decode class");
        return false;
      }
      return true;
    }

    util::StatusObject
    Question::ToJSON() const
    {
      return util::StatusObject{{"qname", qname}, {"qtype", qtype}, {"qclass", qclass}};
    }

    bool
    Question::IsName(const std::string& other) const
    {
      // does other have a . at the end?
      if (other.find_last_of('.') == (other.size() - 1))
        return other == qname;
      // no, add it and retry
      return IsName(other + ".");
    }

    bool
    Question::IsLocalhost() const
    {
      return (qname == "localhost.loki." or llarp::ends_with(qname, ".localhost.loki."));
    }

    bool
    Question::HasSubdomains() const
    {
      const auto parts = split(qname, ".", true);
      return parts.size() >= 3;
    }

    std::string
    Question::Subdomains() const
    {
      if (qname.size() < 2)
        return "";

      size_t pos;

      pos = qname.rfind('.', qname.size() - 2);
      if (pos == std::string::npos or pos == 0)
        return "";

      pos = qname.rfind('.', pos - 1);
      if (pos == std::string::npos or pos == 0)
        return "";

      return qname.substr(0, pos);
    }

    std::string
    Question::Name() const
    {
      return qname.substr(0, qname.find_last_of('.'));
    }

    bool
    Question::HasTLD(const std::string& tld) const
    {
      return qname.find(tld) != std::string::npos
          && qname.rfind(tld) == (qname.size() - tld.size()) - 1;
    }

    std::string
    Question::ToString() const
    {
      return fmt::format("[DNSQuestion qname={} qtype={:x} qclass={:x}]", qname, qtype, qclass);
    }
  }  // namespace dns
}  // namespace llarp