ton/rldp-http-proxy/rldp-http-proxy.cpp

/*
    This file is part of TON Blockchain source code.

    TON Blockchain is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.

    TON Blockchain 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 TON Blockchain.  If not, see <http://www.gnu.org/licenses/>.

    In addition, as a special exception, the copyright holders give permission
    to link the code of portions of this program with the OpenSSL library.
    You must obey the GNU General Public License in all respects for all
    of the code used other than OpenSSL. If you modify file(s) with this
    exception, you may extend this exception to your version of the file(s),
    but you are not obligated to do so. If you do not wish to do so, delete this
    exception statement from your version. If you delete this exception statement
    from all source files in the program, then also delete it here.

    Copyright 2019-2020 Telegram Systems LLP
*/
#include "http/http-server.h"
#include "http/http-client.h"

#include "td/utils/port/signals.h"
#include "td/utils/OptionParser.h"
#include "td/utils/FileLog.h"
#include "td/utils/Random.h"
#include "td/utils/filesystem.h"

#include "auto/tl/ton_api_json.h"
#include "auto/tl/tonlib_api.hpp"

#include "td/actor/MultiPromise.h"

#include "common/errorcode.h"

#include "tonlib/tonlib/TonlibClient.h"

#include "adnl/adnl.h"
#include "rldp/rldp.h"
#include "rldp2/rldp.h"
#include "dht/dht.h"

#include <algorithm>
#include <list>
#include <set>
#include "git.h"
#include "td/utils/BufferedFd.h"
#include "common/delay.h"
#include "td/utils/port/path.h"

#include "tonlib/tonlib/TonlibClientWrapper.h"
#include "DNSResolver.h"

#if TD_DARWIN || TD_LINUX
#include <unistd.h>
#endif

class RldpHttpProxy;

class RldpDispatcher : public ton::adnl::AdnlSenderInterface {
 public:
  RldpDispatcher(td::actor::ActorId<ton::rldp::Rldp> rldp, td::actor::ActorId<ton::rldp2::Rldp> rldp2)
      : rldp_(std::move(rldp)), rldp2_(std::move(rldp2)) {
  }

  void send_message(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, td::BufferSlice data) override {
    td::actor::send_closure(dispatch(dst), &ton::adnl::AdnlSenderInterface::send_message, src, dst, std::move(data));
  }

  void send_query(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, std::string name,
                  td::Promise<td::BufferSlice> promise, td::Timestamp timeout, td::BufferSlice data) override {
    td::actor::send_closure(dispatch(dst), &ton::adnl::AdnlSenderInterface::send_query, src, dst, std::move(name),
                            std::move(promise), timeout, std::move(data));
  }
  void send_query_ex(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, std::string name,
                     td::Promise<td::BufferSlice> promise, td::Timestamp timeout, td::BufferSlice data,
                     td::uint64 max_answer_size) override {
    td::actor::send_closure(dispatch(dst), &ton::adnl::AdnlSenderInterface::send_query_ex, src, dst, std::move(name),
                            std::move(promise), timeout, std::move(data), max_answer_size);
  }
  void get_conn_ip_str(ton::adnl::AdnlNodeIdShort l_id, ton::adnl::AdnlNodeIdShort p_id,
                       td::Promise<td::string> promise) override {
    td::actor::send_closure(rldp_, &ton::adnl::AdnlSenderInterface::get_conn_ip_str, l_id, p_id, std::move(promise));
  }

  void set_supports_rldp2(ton::adnl::AdnlNodeIdShort dst, bool supports) {
    if (supports) {
      supports_rldp2_.insert(dst);
    } else {
      supports_rldp2_.erase(dst);
    }
  }

 private:
  td::actor::ActorId<ton::rldp::Rldp> rldp_;
  td::actor::ActorId<ton::rldp2::Rldp> rldp2_;
  std::set<ton::adnl::AdnlNodeIdShort> supports_rldp2_;

  td::actor::ActorId<ton::adnl::AdnlSenderInterface> dispatch(ton::adnl::AdnlNodeIdShort dst) const {
    if (supports_rldp2_.count(dst)) {
      return rldp2_;
    }
    return rldp_;
  }
};

class HttpRemote : public td::actor::Actor {
 public:
  struct Query {
    std::unique_ptr<ton::http::HttpRequest> request;
    std::shared_ptr<ton::http::HttpPayload> payload;
    td::Timestamp timeout;
    td::Promise<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>> promise;
  };
  HttpRemote(td::IPAddress addr) : addr_(addr) {
  }
  void start_up() override {
    class Cb : public ton::http::HttpClient::Callback {
     public:
      Cb(td::actor::ActorId<HttpRemote> id) : id_(id) {
      }
      void on_ready() override {
        td::actor::send_closure(id_, &HttpRemote::set_ready, true);
      }
      void on_stop_ready() override {
        td::actor::send_closure(id_, &HttpRemote::set_ready, false);
      }

     private:
      td::actor::ActorId<HttpRemote> id_;
    };
    client_ = ton::http::HttpClient::create_multi("", addr_, 1000, 100, std::make_shared<Cb>(actor_id(this)));
  }
  void set_ready(bool ready) {
    ready_ = ready;
  }
  void receive_request(
      std::unique_ptr<ton::http::HttpRequest> request, std::shared_ptr<ton::http::HttpPayload> payload,
      td::Promise<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>>
          promise) {
    if (ready_) {
      bool keep = request->keep_alive();
      auto P = td::PromiseCreator::lambda(
          [promise = std::move(promise), keep](
              td::Result<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>>
                  R) mutable {
            if (R.is_error()) {
              promise.set_error(R.move_as_error());
            } else {
              auto v = R.move_as_ok();
              v.first->set_keep_alive(keep);
              if (v.second->payload_type() != ton::http::HttpPayload::PayloadType::pt_empty &&
                  !v.first->found_content_length() && !v.first->found_transfer_encoding()) {
                v.first->add_header(ton::http::HttpHeader{"Transfer-Encoding", "Chunked"});
              }
              promise.set_value(std::move(v));
            }
          });
      td::actor::send_closure(client_, &ton::http::HttpClient::send_request, std::move(request), std::move(payload),
                              td::Timestamp::never(), std::move(P));
    } else {
      ton::http::answer_error(ton::http::HttpStatusCode::status_bad_request, "", std::move(promise));
    }
  }

 private:
  td::IPAddress addr_;
  bool ready_ = true;
  td::actor::ActorOwn<ton::http::HttpClient> client_;
};

td::BufferSlice create_error_response(const std::string &proto_version, int code, const std::string &reason) {
  return ton::create_serialize_tl_object<ton::ton_api::http_response>(
      proto_version, code, reason, std::vector<ton::tl_object_ptr<ton::ton_api::http_header>>(), true);
}

const std::string PROXY_SITE_VERISON_HEADER_NAME = "Ton-Proxy-Site-Version";
const std::string PROXY_ENTRY_VERISON_HEADER_NAME = "Ton-Proxy-Entry-Version";
const std::string PROXY_VERSION_HEADER = PSTRING() << "Commit: " << GitMetadata::CommitSHA1()
                                                   << ", Date: " << GitMetadata::CommitDate();
const td::uint64 CAPABILITY_RLDP2 = 1;
const td::uint64 CAPABILITIES = 1;

using RegisteredPayloadSenderGuard =
    std::unique_ptr<std::pair<td::actor::ActorId<RldpHttpProxy>, td::Bits256>,
                    std::function<void(std::pair<td::actor::ActorId<RldpHttpProxy>, td::Bits256> *)>>;

class HttpRldpPayloadReceiver : public td::actor::Actor {
 public:
  HttpRldpPayloadReceiver(std::shared_ptr<ton::http::HttpPayload> payload, td::Bits256 transfer_id,
                          ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort local_id,
                          td::actor::ActorId<ton::adnl::Adnl> adnl,
                          td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp, bool is_tunnel = false)
      : payload_(std::move(payload))
      , id_(transfer_id)
      , src_(src)
      , local_id_(local_id)
      , adnl_(adnl)
      , rldp_(rldp)
      , is_tunnel_(is_tunnel) {
  }

  void start_up() override {
    class Cb : public ton::http::HttpPayload::Callback {
     public:
      Cb(td::actor::ActorId<HttpRldpPayloadReceiver> id) : self_id_(id) {
      }
      void run(size_t ready_bytes) override {
        if (!reached_ && ready_bytes < watermark_) {
          reached_ = true;
          td::actor::send_closure(self_id_, &HttpRldpPayloadReceiver::request_more_data);
        } else if (reached_ && ready_bytes >= watermark_) {
          reached_ = false;
        }
      }
      void completed() override {
      }

     private:
      size_t watermark_ = watermark();
      bool reached_ = false;
      td::actor::ActorId<HttpRldpPayloadReceiver> self_id_;
    };

    payload_->add_callback(std::make_unique<Cb>(actor_id(this)));
    request_more_data();
  }

  void request_more_data() {
    LOG(INFO) << "HttpPayloadReceiver: sent=" << sent_ << " completed=" << payload_->parse_completed()
              << " ready=" << payload_->ready_bytes() << " watermark=" << watermark();
    if (sent_ || payload_->parse_completed()) {
      return;
    }
    if (payload_->ready_bytes() >= watermark()) {
      return;
    }
    sent_ = true;
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::BufferSlice> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &HttpRldpPayloadReceiver::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &HttpRldpPayloadReceiver::add_data, R.move_as_ok());
      }
    });

    auto f = ton::create_serialize_tl_object<ton::ton_api::http_getNextPayloadPart>(
        id_, seqno_++, static_cast<td::int32>(chunk_size()));
    auto timeout = td::Timestamp::in(is_tunnel_ ? 60.0 : 15.0);
    td::actor::send_closure(rldp_, &ton::adnl::AdnlSenderInterface::send_query_ex, local_id_, src_, "payload part",
                            std::move(P), timeout, std::move(f), 2 * chunk_size() + 1024);
  }

  void add_data(td::BufferSlice data) {
    LOG(INFO) << "HttpPayloadReceiver: received answer (size " << data.size() << ")";
    auto F = ton::fetch_tl_object<ton::ton_api::http_payloadPart>(data, true);
    if (F.is_error()) {
      abort_query(F.move_as_error());
      return;
    }
    auto f = F.move_as_ok();
    LOG(INFO) << "HttpPayloadReceiver: received answer datasize=" << f->data_.size()
              << " trailers_cnt=" << f->trailer_.size() << " last=" << f->last_;
    if (f->data_.size() != 0) {
      payload_->add_chunk(std::move(f->data_));
    }
    for (auto &x : f->trailer_) {
      ton::http::HttpHeader h{x->name_, x->value_};
      auto S = h.basic_check();
      if (S.is_error()) {
        abort_query(S.move_as_error());
        return;
      }
      payload_->add_trailer(std::move(h));
    }
    sent_ = false;
    if (f->last_) {
      payload_->complete_parse();
      LOG(INFO) << "received HTTP payload";
      stop();
    } else {
      if (payload_->ready_bytes() < watermark()) {
        request_more_data();
      }
    }
  }

  void abort_query(td::Status error) {
    LOG(INFO) << "failed to receive HTTP payload: " << error;
    if (payload_) {
      payload_->set_error();
    }
    stop();
  }

 private:
  static constexpr size_t watermark() {
    return (1 << 21) - (1 << 11);
  }
  static constexpr size_t chunk_size() {
    return (1 << 21) - (1 << 11);
  }

  std::shared_ptr<ton::http::HttpPayload> payload_;

  td::Bits256 id_;

  ton::adnl::AdnlNodeIdShort src_;
  ton::adnl::AdnlNodeIdShort local_id_;
  td::actor::ActorId<ton::adnl::Adnl> adnl_;
  td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp_;

  bool sent_ = false;
  td::int32 seqno_ = 0;
  bool is_tunnel_;
};

class HttpRldpPayloadSender : public td::actor::Actor {
 public:
  HttpRldpPayloadSender(std::shared_ptr<ton::http::HttpPayload> payload, td::Bits256 transfer_id,
                        ton::adnl::AdnlNodeIdShort local_id, td::actor::ActorId<ton::adnl::Adnl> adnl,
                        td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp,
                        td::actor::ActorId<RldpHttpProxy> proxy, bool is_tunnel = false)
      : payload_(std::move(payload))
      , id_(transfer_id)
      , local_id_(local_id)
      , adnl_(adnl)
      , rldp_(rldp)
      , proxy_(proxy)
      , is_tunnel_(is_tunnel) {
  }

  std::string generate_prefix() const {
    std::string x(static_cast<size_t>(36), '\0');
    auto S = td::MutableSlice{x};
    CHECK(S.size() == 36);

    auto id = ton::ton_api::http_getNextPayloadPart::ID;
    S.copy_from(td::Slice(reinterpret_cast<const td::uint8 *>(&id), 4));
    S.remove_prefix(4);
    S.copy_from(id_.as_slice());
    return x;
  }

  void start_up() override;

  void registered_sender(RegisteredPayloadSenderGuard guard) {
    guard_ = std::move(guard);
  }

  void try_answer_query(bool from_timer = false) {
    if (from_timer) {
      active_timer_ = false;
    }
    if (!cur_query_promise_) {
      return;
    }
    if (payload_->is_error()) {
      return;
    }
    if (payload_->parse_completed() || payload_->ready_bytes() >= ton::http::HttpRequest::low_watermark()) {
      answer_query();
    } else if (!is_tunnel_ || payload_->ready_bytes() == 0) {
      return;
    } else if (from_timer) {
      answer_query();
    } else if (!active_timer_) {
      active_timer_ = true;
      ton::delay_action(
          [SelfId = actor_id(this)]() {
            td::actor::send_closure(SelfId, &HttpRldpPayloadSender::try_answer_query, true);
          },
          td::Timestamp::in(0.001));
    }
  }

  void send_data(ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart> query,
                 td::Promise<td::BufferSlice> promise) {
    CHECK(query->id_ == id_);
    if (query->seqno_ != seqno_) {
      LOG(INFO) << "seqno mismatch. closing http transfer";
      stop();
      return;
    }

    if (cur_query_promise_) {
      LOG(INFO) << "duplicate http query. closing http transfer";
      stop();
      return;
    }

    cur_query_size_ = query->max_chunk_size_;
    if (cur_query_size_ > watermark()) {
      cur_query_size_ = watermark();
    }
    cur_query_promise_ = std::move(promise);

    LOG(INFO) << "received request. size=" << cur_query_size_ << " parse_completed=" << payload_->parse_completed()
              << " ready_bytes=" << payload_->ready_bytes();

    alarm_timestamp() = td::Timestamp::in(is_tunnel_ ? 50.0 : 10.0);
    try_answer_query(false);
  }

  void receive_query(ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart> f,
                     td::Promise<td::BufferSlice> promise) {
    send_data(std::move(f), std::move(promise));
  }

  void alarm() override {
    if (cur_query_promise_) {
      if (is_tunnel_) {
        answer_query();
        return;
      }
      LOG(INFO) << "timeout on inbound connection. closing http transfer";
    } else {
      LOG(INFO) << "timeout on RLDP connection. closing http transfer";
    }
    stop();
  }

  void answer_query() {
    cur_query_promise_.set_value(ton::serialize_tl_object(payload_->store_tl(cur_query_size_), true));
    if (payload_->written()) {
      LOG(INFO) << "sent HTTP payload";
      stop();
    }
    seqno_++;

    alarm_timestamp() = td::Timestamp::in(is_tunnel_ ? 60.0 : 30.0);
  }

  void abort_query(td::Status error) {
    LOG(INFO) << error;
    stop();
  }

 private:
  static constexpr size_t watermark() {
    return (1 << 21) - (1 << 11);
  }

  std::shared_ptr<ton::http::HttpPayload> payload_;

  td::Bits256 id_;
  RegisteredPayloadSenderGuard guard_;

  td::int32 seqno_ = 0;

  ton::adnl::AdnlNodeIdShort local_id_;
  td::actor::ActorId<ton::adnl::Adnl> adnl_;
  td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp_;
  td::actor::ActorId<RldpHttpProxy> proxy_;

  size_t cur_query_size_;
  td::Promise<td::BufferSlice> cur_query_promise_;
  bool is_tunnel_, active_timer_ = false;
};

class RldpHttpProxy;

class TcpToRldpRequestSender : public td::actor::Actor {
 public:
  TcpToRldpRequestSender(
      ton::adnl::AdnlNodeIdShort local_id, std::string host, std::unique_ptr<ton::http::HttpRequest> request,
      std::shared_ptr<ton::http::HttpPayload> request_payload,
      td::Promise<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>> promise,
      td::actor::ActorId<ton::adnl::Adnl> adnl, td::actor::ActorId<ton::dht::Dht> dht,
      td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp, td::actor::ActorId<RldpHttpProxy> proxy,
      td::actor::ActorId<DNSResolver> dns_resolver, ton::adnl::AdnlNodeIdShort storage_gateway)
      : local_id_(local_id)
      , host_(std::move(host))
      , request_(std::move(request))
      , request_payload_(std::move(request_payload))
      , promise_(std::move(promise))
      , adnl_(adnl)
      , dht_(dht)
      , rldp_(rldp)
      , proxy_(proxy)
      , dns_resolver_(dns_resolver)
      , storage_gateway_(storage_gateway) {
  }

  void start_up() override {
    td::Random::secure_bytes(id_.as_slice());
    request_tl_ = request_->store_tl(id_);
    resolve(host_);
  }

  void resolve(std::string host);
  void resolved(ton::adnl::AdnlNodeIdShort id);

  void got_result(td::BufferSlice data) {
    auto F = ton::fetch_tl_object<ton::ton_api::http_response>(data, true);
    if (F.is_error()) {
      abort_query(F.move_as_error());
      return;
    }
    auto f = F.move_as_ok();
    auto R = ton::http::HttpResponse::create(f->http_version_, f->status_code_, f->reason_, f->no_payload_, true,
                                             is_tunnel() && f->status_code_ == 200);
    if (R.is_error()) {
      abort_query(R.move_as_error());
      return;
    }
    response_ = R.move_as_ok();
    for (auto &e : f->headers_) {
      ton::http::HttpHeader h{e->name_, e->value_};
      auto S = h.basic_check();
      if (S.is_error()) {
        abort_query(S.move_as_error());
        return;
      }
      response_->add_header(std::move(h));
    }
    response_->add_header({PROXY_ENTRY_VERISON_HEADER_NAME, PROXY_VERSION_HEADER});
    auto S = response_->complete_parse_header();
    if (S.is_error()) {
      abort_query(S.move_as_error());
      return;
    }

    response_payload_ = response_->create_empty_payload().move_as_ok();

    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &TcpToRldpRequestSender::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &TcpToRldpRequestSender::finished_payload_transfer);
      }
    });
    if (f->no_payload_) {
      response_payload_->complete_parse();
    } else {
      td::actor::create_actor<HttpRldpPayloadReceiver>("HttpPayloadReceiver", response_payload_, id_, dst_, local_id_,
                                                       adnl_, rldp_, is_tunnel())
          .release();
    }

    promise_.set_value(std::make_pair(std::move(response_), std::move(response_payload_)));
    stop();
  };

  void finished_payload_transfer() {
    stop();
  }

  void abort_query(td::Status error) {
    LOG(INFO) << "aborting http over rldp query: " << error;
    promise_.set_error(std::move(error));
    stop();
  }

 protected:
  bool is_tunnel() const {
    return request_->method() == "CONNECT";
  }

  td::Bits256 id_;

  ton::adnl::AdnlNodeIdShort local_id_;
  std::string host_;
  ton::adnl::AdnlNodeIdShort dst_;

  std::unique_ptr<ton::http::HttpRequest> request_;
  std::shared_ptr<ton::http::HttpPayload> request_payload_;
  ton::tl_object_ptr<ton::ton_api::http_request> request_tl_;

  td::Promise<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>> promise_;

  td::actor::ActorId<ton::adnl::Adnl> adnl_;
  td::actor::ActorId<ton::dht::Dht> dht_;
  td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp_;
  td::actor::ActorId<RldpHttpProxy> proxy_;
  td::actor::ActorId<DNSResolver> dns_resolver_;
  ton::adnl::AdnlNodeIdShort storage_gateway_ = ton::adnl::AdnlNodeIdShort::zero();

  bool dns_resolve_sent_ = false;

  std::unique_ptr<ton::http::HttpResponse> response_;
  std::shared_ptr<ton::http::HttpPayload> response_payload_;
};

class RldpTcpTunnel : public td::actor::Actor, private td::ObserverBase {
 public:
  RldpTcpTunnel(td::Bits256 transfer_id, ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort local_id,
                td::actor::ActorId<ton::adnl::Adnl> adnl, td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp,
                td::actor::ActorId<RldpHttpProxy> proxy, td::SocketFd fd)
      : id_(transfer_id)
      , src_(src)
      , local_id_(local_id)
      , adnl_(std::move(adnl))
      , rldp_(std::move(rldp))
      , proxy_(std::move(proxy))
      , fd_(std::move(fd)) {
  }

  void start_up() override;

  void tear_down() override {
    LOG(INFO) << "RldpTcpTunnel: tear_down";
    td::actor::SchedulerContext::get()->get_poll().unsubscribe(fd_.get_poll_info().get_pollable_fd_ref());
  }

  void registered_sender(RegisteredPayloadSenderGuard guard) {
    guard_ = std::move(guard);
  }

  void notify() override {
    td::actor::send_closure(self_, &RldpTcpTunnel::process);
  }

  void request_data() {
    if (close_ || sent_request_) {
      return;
    }
    sent_request_ = true;
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::BufferSlice> R) {
      td::actor::send_closure(SelfId, &RldpTcpTunnel::got_data_from_rldp, std::move(R));
    });

    auto f = ton::create_serialize_tl_object<ton::ton_api::http_getNextPayloadPart>(id_, out_seqno_++,
                                                                                    (1 << 21) - (1 << 11));
    td::actor::send_closure(rldp_, &ton::adnl::AdnlSenderInterface::send_query_ex, local_id_, src_, "payload part",
                            std::move(P), td::Timestamp::in(60.0), std::move(f), (1 << 21) + 1024);
  }

  void receive_query(ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart> f,
                     td::Promise<td::BufferSlice> promise) {
    if (cur_promise_) {
      LOG(INFO) << "failed to process query: previous query is active";
      promise.set_error(td::Status::Error("previous query is active"));
      return;
    }
    if (f->seqno_ != cur_seqno_) {
      LOG(INFO) << "failed to process query: seqno mismatch";
      promise.set_error(td::Status::Error("seqno mismatch"));
      return;
    }
    LOG(INFO) << "RldpTcpTunnel: received query, seqno=" << cur_seqno_;
    cur_promise_ = std::move(promise);
    cur_max_chunk_size_ = f->max_chunk_size_;
    alarm_timestamp() = td::Timestamp::in(50.0);
    process();
  }

  void got_data_from_rldp(td::Result<td::BufferSlice> R) {
    if (R.is_error()) {
      abort(R.move_as_error());
      return;
    }
    td::BufferSlice data = R.move_as_ok();
    LOG(INFO) << "RldpTcpTunnel: received data from rldp: size=" << data.size();
    sent_request_ = false;
    auto F = ton::fetch_tl_object<ton::ton_api::http_payloadPart>(data, true);
    if (F.is_error()) {
      abort(F.move_as_error());
      return;
    }
    auto f = F.move_as_ok();
    fd_.output_buffer().append(std::move(f->data_));
    if (f->last_) {
      got_last_part_ = true;
    }
    process();
  }

  void process() {
    if (!close_) {
      auto status = [&] {
        TRY_STATUS(fd_.flush_read());
        TRY_STATUS(fd_.flush_write());
        close_ = td::can_close(fd_);
        return td::Status::OK();
      }();
      if (status.is_error()) {
        abort(std::move(status));
        return;
      }
    }
    if (got_last_part_) {
      close_ = true;
    }
    answer_query();
    request_data();
  }

  void answer_query(bool allow_empty = false, bool from_timer = false) {
    if (from_timer) {
      active_timer_ = false;
    }
    auto &input = fd_.input_buffer();
    if (cur_promise_ && (!input.empty() || close_ || allow_empty)) {
      if (!from_timer && !close_ && !allow_empty && input.size() < ton::http::HttpRequest::low_watermark()) {
        if (!active_timer_) {
          active_timer_ = true;
          ton::delay_action(
              [SelfId = actor_id(this)]() {
                td::actor::send_closure(SelfId, &RldpTcpTunnel::answer_query, false, true);
              },
              td::Timestamp::in(0.001));
        }
        return;
      }
      size_t s = std::min<size_t>(input.size(), cur_max_chunk_size_);
      td::BufferSlice data(s);
      LOG(INFO) << "RldpTcpTunnel: sending data to rldp: size=" << data.size();
      input.advance(s, td::as_mutable_slice(data));
      cur_promise_.set_result(ton::create_serialize_tl_object<ton::ton_api::http_payloadPart>(
          std::move(data), std::vector<ton::tl_object_ptr<ton::ton_api::http_header>>(), close_));
      ++cur_seqno_;
      cur_promise_.reset();
      alarm_timestamp() = td::Timestamp::never();
      if (close_) {
        stop();
        return;
      }
    }
  }

  void alarm() override {
    answer_query(true, false);
  }

  void abort(td::Status status) {
    LOG(INFO) << "RldpTcpTunnel error: " << status;
    if (cur_promise_) {
      cur_promise_.set_error(status.move_as_error());
    }
    stop();
  }

 private:
  std::string generate_prefix() const {
    std::string x(static_cast<size_t>(36), '\0');
    auto S = td::MutableSlice{x};
    CHECK(S.size() == 36);

    auto id = ton::ton_api::http_getNextPayloadPart::ID;
    S.copy_from(td::Slice(reinterpret_cast<const td::uint8 *>(&id), 4));
    S.remove_prefix(4);
    S.copy_from(id_.as_slice());
    return x;
  }

  td::Bits256 id_;
  RegisteredPayloadSenderGuard guard_;

  ton::adnl::AdnlNodeIdShort src_;
  ton::adnl::AdnlNodeIdShort local_id_;
  td::actor::ActorId<ton::adnl::Adnl> adnl_;
  td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp_;
  td::actor::ActorId<RldpHttpProxy> proxy_;

  td::BufferedFd<td::SocketFd> fd_;

  td::actor::ActorId<RldpTcpTunnel> self_;

  td::int32 cur_seqno_ = 0, cur_max_chunk_size_ = 0;
  td::Promise<td::BufferSlice> cur_promise_;
  td::int32 out_seqno_ = 0;
  bool close_ = false, sent_request_ = false, got_last_part_ = false;
  bool active_timer_ = false;
};

class RldpToTcpRequestSender : public td::actor::Actor {
 public:
  RldpToTcpRequestSender(td::Bits256 id, ton::adnl::AdnlNodeIdShort local_id, ton::adnl::AdnlNodeIdShort dst,
                         std::unique_ptr<ton::http::HttpRequest> request,
                         std::shared_ptr<ton::http::HttpPayload> request_payload, td::Promise<td::BufferSlice> promise,
                         td::actor::ActorId<ton::adnl::Adnl> adnl,
                         td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp,
                         td::actor::ActorId<RldpHttpProxy> proxy, td::actor::ActorId<HttpRemote> remote)
      : id_(id)
      , local_id_(local_id)
      , dst_(dst)
      , request_(std::move(request))
      , request_payload_(std::move(request_payload))
      , proto_version_(request_->proto_version())
      , promise_(std::move(promise))
      , adnl_(adnl)
      , rldp_(rldp)
      , proxy_(proxy)
      , remote_(std::move(remote)) {
  }
  void start_up() override {
    auto P = td::PromiseCreator::lambda(
        [SelfId = actor_id(this)](
            td::Result<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>>
                R) {
          if (R.is_error()) {
            td::actor::send_closure(SelfId, &RldpToTcpRequestSender::abort_query, R.move_as_error());
          } else {
            td::actor::send_closure(SelfId, &RldpToTcpRequestSender::got_result, R.move_as_ok());
          }
        });
    td::actor::send_closure(remote_, &HttpRemote::receive_request, std::move(request_), request_payload_, std::move(P));
    td::actor::create_actor<HttpRldpPayloadReceiver>("HttpPayloadReceiver(R)", std::move(request_payload_), id_, dst_,
                                                     local_id_, adnl_, rldp_)
        .release();
  }

  void got_result(std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>> R) {
    td::actor::create_actor<HttpRldpPayloadSender>("HttpPayloadSender(R)", std::move(R.second), id_, local_id_, adnl_,
                                                   rldp_, proxy_)
        .release();
    R.first->add_header({PROXY_SITE_VERISON_HEADER_NAME, PROXY_VERSION_HEADER});
    auto f = ton::serialize_tl_object(R.first->store_tl(), true);
    promise_.set_value(std::move(f));
    stop();
  }

  void abort_query(td::Status error) {
    LOG(INFO) << "aborting http over rldp query: " << error;
    promise_.set_result(create_error_response(proto_version_, 502, "Bad Gateway"));
    stop();
  }

 protected:
  td::Bits256 id_;

  ton::adnl::AdnlNodeIdShort local_id_;
  ton::adnl::AdnlNodeIdShort dst_;

  std::unique_ptr<ton::http::HttpRequest> request_;
  std::shared_ptr<ton::http::HttpPayload> request_payload_;
  std::string proto_version_;

  td::Promise<td::BufferSlice> promise_;

  td::actor::ActorId<ton::adnl::Adnl> adnl_;
  td::actor::ActorId<ton::adnl::AdnlSenderInterface> rldp_;
  td::actor::ActorId<RldpHttpProxy> proxy_;

  td::actor::ActorId<HttpRemote> remote_;
};

class RldpHttpProxy : public td::actor::Actor {
 public:
  RldpHttpProxy() = default;

  void set_port(td::uint16 port) {
    if (port_) {
      LOG(ERROR) << "duplicate listening port";
      std::_Exit(2);
    }
    port_ = port;
  }

  void set_global_config(std::string path) {
    global_config_ = std::move(path);
  }

  void set_addr(td::IPAddress addr) {
    addr_ = addr;
  }

  void set_client_port(td::uint16 port) {
    is_client_ = true;
    client_port_ = port;
  }

  void set_local_host(std::string host, td::uint16 port, td::IPAddress remote) {
    hosts_[host].ports_[port].remote_addr_ = remote;
  }

  td::Status load_global_config() {
    TRY_RESULT_PREFIX(conf_data, td::read_file(global_config_), "failed to read: ");
    TRY_RESULT_PREFIX(conf_json, td::json_decode(conf_data.as_slice()), "failed to parse json: ");

    ton::ton_api::config_global conf;
    TRY_STATUS_PREFIX(ton::ton_api::from_json(conf, conf_json.get_object()), "json does not fit TL scheme: ");

    if (!conf.dht_) {
      return td::Status::Error(ton::ErrorCode::error, "does not contain [dht] section");
    }

    TRY_RESULT_PREFIX(dht, ton::dht::Dht::create_global_config(std::move(conf.dht_)), "bad [dht] section: ");
    dht_config_ = std::move(dht);

    return td::Status::OK();
  }

  void store_dht() {
    for (auto &serv : hosts_) {
      if (serv.first != "*") {
        for (auto &serv_id : server_ids_) {
          ton::PublicKey key = ton::pubkeys::Unenc{"http." + serv.first};
          ton::dht::DhtKey dht_key{key.compute_short_id(), "http." + serv.first, 0};
          auto dht_update_rule = ton::dht::DhtUpdateRuleAnybody::create().move_as_ok();
          ton::dht::DhtKeyDescription dht_key_description{std::move(dht_key), key, std::move(dht_update_rule),
                                                          td::BufferSlice()};
          dht_key_description.check().ensure();

          auto ttl = static_cast<td::uint32>(td::Clocks::system() + 3600);
          ton::dht::DhtValue dht_value{std::move(dht_key_description), td::BufferSlice{serv_id.as_slice()}, ttl,
                                       td::BufferSlice("")};

          td::actor::send_closure(dht_, &ton::dht::Dht::set_value, std::move(dht_value), [](td::Unit) {});
        }
      }
    }
    alarm_timestamp() = td::Timestamp::in(60.0);
  }

  void alarm() override {
    store_dht();
  }

  void got_full_id(ton::adnl::AdnlNodeIdShort short_id, ton::adnl::AdnlNodeIdFull full_id) {
    server_ids_full_[short_id] = full_id;
  }

  void run() {
    if (!db_root_.empty()) {
      td::mkpath(db_root_ + "/").ensure();
    } else if (!is_client_) {
      LOG(ERROR) << "DB root is required for server proxy";
      std::_Exit(2);
    }
    keyring_ = ton::keyring::Keyring::create(is_client_ ? std::string("") : (db_root_ + "/keyring"));
    {
      auto S = load_global_config();
      if (S.is_error()) {
        LOG(ERROR) << S;
        std::_Exit(2);
      }
    }
    if (is_client_ && server_ids_.size() > 0) {
      LOG(ERROR) << "client-only node cannot be server";
      std::_Exit(2);
    }
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
      R.ensure();
      td::actor::send_closure(SelfId, &RldpHttpProxy::run_cont);
    });
    td::MultiPromise mp;
    auto ig = mp.init_guard();
    ig.add_promise(std::move(P));
    for (auto &x : server_ids_) {
      auto Q = td::PromiseCreator::lambda([promise = ig.get_promise(), SelfId = actor_id(this),
                                           x](td::Result<ton::PublicKey> R) mutable {
        if (R.is_error()) {
          promise.set_error(R.move_as_error());
        } else {
          td::actor::send_closure(SelfId, &RldpHttpProxy::got_full_id, x, ton::adnl::AdnlNodeIdFull{R.move_as_ok()});
          promise.set_value(td::Unit());
        }
      });
      td::actor::send_closure(keyring_, &ton::keyring::Keyring::get_public_key, x.pubkey_hash(), std::move(Q));
    }

    auto conf_dataR = td::read_file(global_config_);
    conf_dataR.ensure();

    ton::tl_object_ptr<tonlib_api::KeyStoreType> key_store;
    if (db_root_.empty()) {
      key_store = tonlib_api::make_object<tonlib_api::keyStoreTypeInMemory>();
    } else {
      td::mkpath(db_root_ + "/tonlib-cache/").ensure();
      key_store = tonlib_api::make_object<tonlib_api::keyStoreTypeDirectory>(db_root_ + "/tonlib-cache/");
    }
    auto tonlib_options = tonlib_api::make_object<tonlib_api::options>(
        tonlib_api::make_object<tonlib_api::config>(conf_dataR.move_as_ok().as_slice().str(), "", false, false),
        std::move(key_store));
    tonlib_client_ = td::actor::create_actor<tonlib::TonlibClientWrapper>("tonlibclient", std::move(tonlib_options));
    dns_resolver_ = td::actor::create_actor<DNSResolver>("dnsresolver", tonlib_client_.get());
  }

  void run_cont() {
    if (is_client_ && hosts_.size() > 0) {
      LOG(ERROR) << "client-only node cannot be server";
      std::_Exit(2);
    }
    if (is_client_ && client_port_ == 0) {
      LOG(ERROR) << "client-only expects client port";
      std::_Exit(2);
    }
    {
      adnl_network_manager_ =
          ton::adnl::AdnlNetworkManager::create(is_client_ ? client_port_ : static_cast<td::uint16>(addr_.get_port()));
      adnl_ = ton::adnl::Adnl::create(is_client_ ? std::string("") : (db_root_), keyring_.get());
      td::actor::send_closure(adnl_, &ton::adnl::Adnl::register_network_manager, adnl_network_manager_.get());
      ton::adnl::AdnlCategoryMask cat_mask;
      cat_mask[0] = true;
      if (is_client_) {
        td::IPAddress addr;
        addr.init_host_port("127.0.0.1", client_port_).ensure();
        td::actor::send_closure(adnl_network_manager_, &ton::adnl::AdnlNetworkManager::add_self_addr, addr,
                                std::move(cat_mask), 0);
      } else {
        td::actor::send_closure(adnl_network_manager_, &ton::adnl::AdnlNetworkManager::add_self_addr, addr_,
                                std::move(cat_mask), 0);
      }

      ton::adnl::AdnlAddressList addr_list;
      if (!is_client_) {
        ton::adnl::AdnlAddress x = ton::adnl::AdnlAddressImpl::create(
            ton::create_tl_object<ton::ton_api::adnl_address_udp>(addr_.get_ipv4(), addr_.get_port()));
        addr_list.add_addr(std::move(x));
      }
      addr_list.set_version(static_cast<td::int32>(td::Clocks::system()));
      addr_list.set_reinit_date(ton::adnl::Adnl::adnl_start_time());
      {
        auto pk = ton::PrivateKey{ton::privkeys::Ed25519::random()};
        auto pub = pk.compute_public_key();
        td::actor::send_closure(keyring_, &ton::keyring::Keyring::add_key, std::move(pk), true, [](td::Unit) {});
        local_id_ = ton::adnl::AdnlNodeIdShort{pub.compute_short_id()};
        td::actor::send_closure(adnl_, &ton::adnl::Adnl::add_id, ton::adnl::AdnlNodeIdFull{pub}, addr_list,
                                static_cast<td::uint8>(0));

        if (server_ids_.size() == 0 && !is_client_) {
          server_ids_.insert(local_id_);
        }
      }
      {
        auto pk = ton::PrivateKey{ton::privkeys::Ed25519::random()};
        auto pub = pk.compute_public_key();
        td::actor::send_closure(keyring_, &ton::keyring::Keyring::add_key, std::move(pk), true, [](td::Unit) {});
        dht_id_ = ton::adnl::AdnlNodeIdShort{pub.compute_short_id()};
        td::actor::send_closure(adnl_, &ton::adnl::Adnl::add_id, ton::adnl::AdnlNodeIdFull{pub}, addr_list,
                                static_cast<td::uint8>(0));
      }
      for (auto &serv_id : server_ids_) {
        td::actor::send_closure(adnl_, &ton::adnl::Adnl::add_id, server_ids_full_[serv_id], addr_list,
                                static_cast<td::uint8>(0));
      }
    }
    {
      auto D = ton::dht::Dht::create_client(dht_id_, "", dht_config_, keyring_.get(), adnl_.get());
      D.ensure();
      dht_ = D.move_as_ok();
      td::actor::send_closure(adnl_, &ton::adnl::Adnl::register_dht_node, dht_.get());
    }
    if (port_) {
      class Cb : public ton::http::HttpServer::Callback {
       public:
        Cb(td::actor::ActorId<RldpHttpProxy> proxy) : proxy_(proxy) {
        }
        void receive_request(
            std::unique_ptr<ton::http::HttpRequest> request, std::shared_ptr<ton::http::HttpPayload> payload,
            td::Promise<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>>
                promise) override {
          td::actor::send_closure(proxy_, &RldpHttpProxy::receive_http_request, std::move(request), std::move(payload),
                                  std::move(promise));
        }

       private:
        td::actor::ActorId<RldpHttpProxy> proxy_;
      };

      server_ = ton::http::HttpServer::create(port_, std::make_shared<Cb>(actor_id(this)));
    }

    class AdnlPayloadCb : public ton::adnl::Adnl::Callback {
     public:
      AdnlPayloadCb(td::actor::ActorId<RldpHttpProxy> id) : self_id_(id) {
      }
      void receive_message(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst,
                           td::BufferSlice data) override {
      }
      void receive_query(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, td::BufferSlice data,
                         td::Promise<td::BufferSlice> promise) override {
        td::actor::send_closure(self_id_, &RldpHttpProxy::receive_payload_part_request, std::move(data),
                                std::move(promise));
      }

     private:
      td::actor::ActorId<RldpHttpProxy> self_id_;
    };
    class AdnlCapabilitiesCb : public ton::adnl::Adnl::Callback {
     public:
      AdnlCapabilitiesCb(td::actor::ActorId<RldpHttpProxy> id) : self_id_(id) {
      }
      void receive_message(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst,
                           td::BufferSlice data) override {
      }
      void receive_query(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, td::BufferSlice data,
                         td::Promise<td::BufferSlice> promise) override {
        TRY_RESULT_PROMISE(promise, query, ton::fetch_tl_object<ton::ton_api::http_proxy_getCapabilities>(data, true));
        promise.set_result(ton::create_serialize_tl_object<ton::ton_api::http_proxy_capabilities>(CAPABILITIES));
        td::actor::send_closure(self_id_, &RldpHttpProxy::update_peer_capabilities, src, query->capabilities_);
      }

     private:
      td::actor::ActorId<RldpHttpProxy> self_id_;
    };
    class AdnlServerCb : public ton::adnl::Adnl::Callback {
     public:
      AdnlServerCb(td::actor::ActorId<RldpHttpProxy> id) : self_id_(id) {
      }
      void receive_message(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst,
                           td::BufferSlice data) override {
      }
      void receive_query(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, td::BufferSlice data,
                         td::Promise<td::BufferSlice> promise) override {
        td::actor::send_closure(self_id_, &RldpHttpProxy::receive_rldp_request, src, dst, std::move(data),
                                std::move(promise));
      }

     private:
      td::actor::ActorId<RldpHttpProxy> self_id_;
    };
    for (auto &serv_id : server_ids_) {
      td::actor::send_closure(adnl_, &ton::adnl::Adnl::subscribe, serv_id,
                              ton::adnl::Adnl::int_to_bytestring(ton::ton_api::http_request::ID),
                              std::make_unique<AdnlServerCb>(actor_id(this)));
      if (local_id_ != serv_id) {
        td::actor::send_closure(adnl_, &ton::adnl::Adnl::subscribe, serv_id,
                                ton::adnl::Adnl::int_to_bytestring(ton::ton_api::http_getNextPayloadPart::ID),
                                std::make_unique<AdnlPayloadCb>(actor_id(this)));
        td::actor::send_closure(adnl_, &ton::adnl::Adnl::subscribe, serv_id,
                                ton::adnl::Adnl::int_to_bytestring(ton::ton_api::http_proxy_getCapabilities::ID),
                                std::make_unique<AdnlCapabilitiesCb>(actor_id(this)));
      }
    }
    td::actor::send_closure(adnl_, &ton::adnl::Adnl::subscribe, local_id_,
                            ton::adnl::Adnl::int_to_bytestring(ton::ton_api::http_getNextPayloadPart::ID),
                            std::make_unique<AdnlPayloadCb>(actor_id(this)));
    td::actor::send_closure(adnl_, &ton::adnl::Adnl::subscribe, local_id_,
                            ton::adnl::Adnl::int_to_bytestring(ton::ton_api::http_proxy_getCapabilities::ID),
                            std::make_unique<AdnlCapabilitiesCb>(actor_id(this)));

    rldp_ = ton::rldp::Rldp::create(adnl_.get());
    td::actor::send_closure(rldp_, &ton::rldp::Rldp::set_default_mtu, 16 << 10);
    td::actor::send_closure(rldp_, &ton::rldp::Rldp::add_id, local_id_);
    for (auto &serv_id : server_ids_) {
      td::actor::send_closure(rldp_, &ton::rldp::Rldp::add_id, serv_id);
    }

    rldp2_ = ton::rldp2::Rldp::create(adnl_.get());
    td::actor::send_closure(rldp2_, &ton::rldp2::Rldp::set_default_mtu, 16 << 10);
    td::actor::send_closure(rldp2_, &ton::rldp2::Rldp::add_id, local_id_);
    for (auto &serv_id : server_ids_) {
      td::actor::send_closure(rldp2_, &ton::rldp2::Rldp::add_id, serv_id);
    }

    rldp_dispatcher_ = td::actor::create_actor<RldpDispatcher>("RldpDispatcher", rldp_.get(), rldp2_.get());

    store_dht();
  }

  void receive_http_request(
      std::unique_ptr<ton::http::HttpRequest> request, std::shared_ptr<ton::http::HttpPayload> payload,
      td::Promise<std::pair<std::unique_ptr<ton::http::HttpResponse>, std::shared_ptr<ton::http::HttpPayload>>>
          promise) {
    auto host = request->host();
    if (host.size() == 0) {
      host = request->url();
      if (host.size() >= 7 && host.substr(0, 7) == "http://") {
        host = host.substr(7);
      } else if (host.size() >= 8 && host.substr(0, 8) == "https://") {
        host = host.substr(8);
      }
      auto p = host.find('/');
      if (p != std::string::npos) {
        host = host.substr(0, p);
      }
    } else {
      if (host.size() >= 7 && host.substr(0, 7) == "http://") {
        host = host.substr(7);
      } else if (host.size() >= 8 && host.substr(0, 8) == "https://") {
        host = host.substr(8);
      }
      auto p = host.find('/');
      if (p != std::string::npos) {
        host = host.substr(0, p);
      }
    }
    {
      auto p = host.find(':');
      if (p != std::string::npos) {
        host = host.substr(0, p);
      }
    }
    std::transform(host.begin(), host.end(), host.begin(), [](unsigned char c) { return std::tolower(c); });
    bool allow = proxy_all_;
    for (const char *suffix : {".adnl", ".ton", ".bag"}) {
      if (td::ends_with(host, td::Slice(suffix))) {
        allow = true;
      }
    }
    if (!allow) {
      promise.set_error(td::Status::Error(ton::ErrorCode::error, "bad server name"));
      return;
    }

    td::actor::create_actor<TcpToRldpRequestSender>(
        "outboundreq", local_id_, host, std::move(request), std::move(payload), std::move(promise), adnl_.get(),
        dht_.get(), rldp_dispatcher_.get(), actor_id(this), dns_resolver_.get(), storage_gateway_)
        .release();
  }

  void receive_rldp_request(ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort dst, td::BufferSlice data,
                            td::Promise<td::BufferSlice> promise) {
    LOG(INFO) << "got HTTP request over rldp from " << src;
    TRY_RESULT_PROMISE(promise, f, ton::fetch_tl_object<ton::ton_api::http_request>(data, true));
    ask_peer_capabilities(src);
    std::unique_ptr<ton::http::HttpRequest> request;
    auto S = [&]() {
      TRY_RESULT_ASSIGN(request, ton::http::HttpRequest::create(f->method_, f->url_, f->http_version_));
      for (auto &x : f->headers_) {
        ton::http::HttpHeader h{x->name_, x->value_};
        TRY_STATUS(h.basic_check());
        request->add_header(std::move(h));
      }
      TRY_STATUS(request->complete_parse_header());
      return td::Status::OK();
    }();
    if (S.is_error()) {
      LOG(INFO) << "Failed to parse http request: " << S;
      promise.set_result(create_error_response(f->http_version_, 400, "Bad Request"));
      return;
    }
    auto host = request->host();
    td::uint16 port = 80;
    if (host.empty()) {
      host = request->url();
      if (host.size() >= 7 && host.substr(0, 7) == "http://") {
        host = host.substr(7);
      } else if (host.size() >= 8 && host.substr(0, 8) == "https://") {
        host = host.substr(8);
      }
      auto p = host.find('/');
      if (p != std::string::npos) {
        host = host.substr(0, p);
      }
    } else {
      if (host.size() >= 7 && host.substr(0, 7) == "http://") {
        host = host.substr(7);
      } else if (host.size() >= 8 && host.substr(0, 8) == "https://") {
        host = host.substr(8);
      }
      auto p = host.find('/');
      if (p != std::string::npos) {
        host = host.substr(0, p);
      }
    }
    {
      auto p = host.find(':');
      if (p != std::string::npos) {
        try {
          port = (td::uint16)std::stoul(host.substr(p + 1));
        } catch (const std::logic_error &) {
          port = 80;
          promise.set_result(create_error_response(f->http_version_, 400, "Bad Request"));
          return;
        }
        host = host.substr(0, p);
      }
    }
    std::transform(host.begin(), host.end(), host.begin(), [](unsigned char c) { return std::tolower(c); });

    auto it = hosts_.find(host);
    if (it == hosts_.end()) {
      it = hosts_.find("*");
      if (it == hosts_.end()) {
        promise.set_result(create_error_response(f->http_version_, 502, "Bad Gateway"));
        return;
      }
    }
    auto it2 = it->second.ports_.find(port);
    if (it2 == it->second.ports_.end()) {
      promise.set_result(create_error_response(f->http_version_, 502, "Bad Gateway"));
      return;
    }
    auto &server = it2->second;
    if (request->method() == "CONNECT") {
      LOG(INFO) << "starting HTTP tunnel over RLDP to " << server.remote_addr_;
      start_tcp_tunnel(f->id_, src, dst, f->http_version_, server.remote_addr_, std::move(promise));
      return;
    }

    if (server.http_remote_.empty()) {
      server.http_remote_ = td::actor::create_actor<HttpRemote>("remote", server.remote_addr_);
    }

    auto payload = request->create_empty_payload();
    if (payload.is_error()) {
      promise.set_result(create_error_response(f->http_version_, 502, "Bad Gateway"));
      return;
    }

    LOG(INFO) << "starting HTTP over RLDP request";
    td::actor::create_actor<RldpToTcpRequestSender>("inboundreq", f->id_, dst, src, std::move(request),
                                                    payload.move_as_ok(), std::move(promise), adnl_.get(),
                                                    rldp_dispatcher_.get(), actor_id(this), server.http_remote_.get())
        .release();
  }

  void start_tcp_tunnel(td::Bits256 id, ton::adnl::AdnlNodeIdShort src, ton::adnl::AdnlNodeIdShort local_id,
                        std::string http_version, td::IPAddress ip, td::Promise<td::BufferSlice> promise) {
    auto fd = td::SocketFd::open(ip);
    if (fd.is_error()) {
      promise.set_result(create_error_response(http_version, 502, "Bad Gateway"));
      return;
    }
    td::actor::create_actor<RldpTcpTunnel>(td::actor::ActorOptions().with_name("tunnel").with_poll(), id, src, local_id,
                                           adnl_.get(), rldp_dispatcher_.get(), actor_id(this), fd.move_as_ok())
        .release();
    std::vector<ton::tl_object_ptr<ton::ton_api::http_header>> headers;
    headers.push_back(
        ton::create_tl_object<ton::ton_api::http_header>(PROXY_SITE_VERISON_HEADER_NAME, PROXY_VERSION_HEADER));
    promise.set_result(ton::create_serialize_tl_object<ton::ton_api::http_response>(
        http_version, 200, "Connection Established", std::move(headers), false));
  }

  void receive_payload_part_request(td::BufferSlice data, td::Promise<td::BufferSlice> promise) {
    auto F = ton::fetch_tl_object<ton::ton_api::http_getNextPayloadPart>(data, true);
    if (F.is_error()) {
      LOG(INFO) << "failed to parse query: " << F.error();
      promise.set_error(F.move_as_error());
      return;
    }
    auto f = F.move_as_ok();
    auto it = payload_senders_.find(f->id_);
    if (it == payload_senders_.end()) {
      LOG(INFO) << "failed to answer query: unknown request id";
      promise.set_error(td::Status::Error("unknown request id"));
      return;
    }
    it->second(std::move(f), std::move(promise));
  }

  void register_payload_sender(
      td::Bits256 id,
      std::function<void(ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart>, td::Promise<td::BufferSlice>)> f,
      td::Promise<RegisteredPayloadSenderGuard> promise) {
    auto &f1 = payload_senders_[id];
    if (f1) {
      promise.set_error(td::Status::Error("duplicate id"));
      return;
    }
    f1 = std::move(f);
    promise.set_result(RegisteredPayloadSenderGuard(
        new std::pair<td::actor::ActorId<RldpHttpProxy>, td::Bits256>(actor_id(this), id),
        [](std::pair<td::actor::ActorId<RldpHttpProxy>, td::Bits256> *x) {
          td::actor::send_closure(x->first, &RldpHttpProxy::unregister_payload_sender, x->second);
          delete x;
        }));
  }

  void unregister_payload_sender(td::Bits256 id) {
    payload_senders_.erase(id);
  }

  void add_adnl_addr(ton::adnl::AdnlNodeIdShort id) {
    server_ids_.insert(id);
  }

  void set_db_root(std::string db_root) {
    db_root_ = std::move(db_root);
  }

  void set_proxy_all(bool value) {
    proxy_all_ = value;
  }

  void set_storage_gateway(ton::adnl::AdnlNodeIdShort id) {
    storage_gateway_ = id;
  }

  void update_peer_capabilities(ton::adnl::AdnlNodeIdShort peer, td::uint64 capabilities) {
    auto &c = peer_capabilities_[peer];
    if (c.capabilities != capabilities) {
      LOG(DEBUG) << "Update capabilities of peer " << peer << " : " << capabilities;
    }
    c.capabilities = capabilities;
    c.received = true;
    td::actor::send_closure(rldp_dispatcher_, &RldpDispatcher::set_supports_rldp2, peer,
                            capabilities & CAPABILITY_RLDP2);
  }

  void ask_peer_capabilities(ton::adnl::AdnlNodeIdShort peer) {
    auto &c = peer_capabilities_[peer];
    if (!c.received && c.retry_at.is_in_past()) {
      c.retry_at = td::Timestamp::in(30.0);
      auto send_query = [&, this, SelfId = actor_id(this)](const ton::adnl::AdnlNodeIdShort &local_id) {
        td::actor::send_closure(
            adnl_, &ton::adnl::Adnl::send_query, local_id, peer, "q",
            [SelfId, peer](td::Result<td::BufferSlice> R) {
              if (R.is_error()) {
                return;
              }
              auto r_obj = ton::fetch_tl_object<ton::ton_api::http_proxy_capabilities>(R.move_as_ok(), true);
              if (r_obj.is_error()) {
                return;
              }
              td::actor::send_closure(SelfId, &RldpHttpProxy::update_peer_capabilities, peer,
                                      r_obj.ok()->capabilities_);
            },
            td::Timestamp::in(3.0),
            ton::create_serialize_tl_object<ton::ton_api::http_proxy_getCapabilities>(CAPABILITIES));
      };
      for (const ton::adnl::AdnlNodeIdShort &local_id : server_ids_) {
        if (local_id != local_id_) {
          send_query(local_id);
        }
      }
      send_query(local_id_);
    }
  }

 private:
  struct Host {
    struct Server {
      td::IPAddress remote_addr_;
      td::actor::ActorOwn<HttpRemote> http_remote_;
    };
    std::map<td::uint16, Server> ports_;
  };

  td::uint16 port_{0};
  td::IPAddress addr_;
  std::string global_config_;

  bool is_client_{false};
  td::uint16 client_port_{0};

  std::set<ton::adnl::AdnlNodeIdShort> server_ids_;
  std::map<ton::adnl::AdnlNodeIdShort, ton::adnl::AdnlNodeIdFull> server_ids_full_;
  ton::adnl::AdnlNodeIdShort local_id_;
  ton::adnl::AdnlNodeIdShort dht_id_;

  td::actor::ActorOwn<ton::http::HttpServer> server_;
  std::map<std::string, Host> hosts_;

  td::actor::ActorOwn<ton::keyring::Keyring> keyring_;
  td::actor::ActorOwn<ton::adnl::AdnlNetworkManager> adnl_network_manager_;
  td::actor::ActorOwn<ton::adnl::Adnl> adnl_;
  td::actor::ActorOwn<ton::dht::Dht> dht_;
  td::actor::ActorOwn<ton::rldp::Rldp> rldp_;
  td::actor::ActorOwn<ton::rldp2::Rldp> rldp2_;
  td::actor::ActorOwn<RldpDispatcher> rldp_dispatcher_;

  std::shared_ptr<ton::dht::DhtGlobalConfig> dht_config_;

  std::string db_root_ = ".";
  bool proxy_all_ = false;

  td::actor::ActorOwn<tonlib::TonlibClientWrapper> tonlib_client_;
  td::actor::ActorOwn<DNSResolver> dns_resolver_;
  ton::adnl::AdnlNodeIdShort storage_gateway_ = ton::adnl::AdnlNodeIdShort::zero();

  std::map<td::Bits256,
           std::function<void(ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart>, td::Promise<td::BufferSlice>)>>
      payload_senders_;

  struct PeerCapabilities {
    td::uint64 capabilities = 0;
    bool received = false;
    td::Timestamp retry_at = td::Timestamp::now();
  };
  std::map<ton::adnl::AdnlNodeIdShort, PeerCapabilities> peer_capabilities_;
};

void TcpToRldpRequestSender::resolve(std::string host) {
  auto S = td::Slice(host);
  if (td::ends_with(S, ".bag")) {
    if (storage_gateway_.is_zero()) {
      abort_query(td::Status::Error("storage gateway is not set"));
      return;
    }
    td::Slice bag_id = S.substr(0, S.size() - 4);
    td::Slice url = request_tl_->url_;
    if (td::begins_with(url, "http://")) {
      url.remove_prefix(7);
    }
    size_t pos = url.find('/');
    if (pos == td::Slice::npos) {
      url = "/";
    } else {
      url = url.substr(pos);
    }
    request_tl_->url_ = (PSTRING() << "/gateway/" << bag_id << url);
    host = storage_gateway_.serialize() + ".adnl";
    for (auto &header : request_tl_->headers_) {
      if (td::to_lower(header->name_) == "host") {
        header->value_ = host;
        break;
      }
    }
    resolved(storage_gateway_);
    return;
  }
  if (td::ends_with(S, ".adnl")) {
    S.truncate(S.size() - 5);
    auto R = ton::adnl::AdnlNodeIdShort::parse(S);
    if (R.is_error()) {
      abort_query(R.move_as_error_prefix("failed to parse adnl addr: "));
      return;
    }
    resolved(R.move_as_ok());
    return;
  }
  if (dns_resolve_sent_) {
    abort_query(td::Status::Error(PSTRING() << "unexpected dns result: " << host));
    return;
  }
  dns_resolve_sent_ = true;
  td::actor::send_closure(dns_resolver_, &DNSResolver::resolve, host,
                          [SelfId = actor_id(this)](td::Result<std::string> R) {
                            if (R.is_error()) {
                              td::actor::send_closure(SelfId, &TcpToRldpRequestSender::abort_query,
                                                      R.move_as_error_prefix("failed to resolve: "));
                            } else {
                              td::actor::send_closure(SelfId, &TcpToRldpRequestSender::resolve, R.move_as_ok());
                            }
                          });
}

void TcpToRldpRequestSender::resolved(ton::adnl::AdnlNodeIdShort id) {
  dst_ = id;
  td::actor::send_closure(proxy_, &RldpHttpProxy::ask_peer_capabilities, id);

  auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::BufferSlice> R) {
    if (R.is_error()) {
      td::actor::send_closure(SelfId, &TcpToRldpRequestSender::abort_query, R.move_as_error());
    } else {
      td::actor::send_closure(SelfId, &TcpToRldpRequestSender::got_result, R.move_as_ok());
    }
  });

  td::actor::create_actor<HttpRldpPayloadSender>("HttpPayloadSender", request_payload_, id_, local_id_, adnl_, rldp_,
                                                 proxy_, is_tunnel())
      .release();

  auto f = ton::serialize_tl_object(request_tl_, true);
  td::actor::send_closure(rldp_, &ton::adnl::AdnlSenderInterface::send_query_ex, local_id_, dst_,
                          "http request over rldp", std::move(P), td::Timestamp::in(30.0), std::move(f), 16 << 10);
}

void HttpRldpPayloadSender::start_up() {
  td::actor::send_closure(
      proxy_, &RldpHttpProxy::register_payload_sender, id_,
      [SelfId = actor_id(this)](ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart> f,
                                td::Promise<td::BufferSlice> promise) {
        td::actor::send_closure(SelfId, &HttpRldpPayloadSender::receive_query, std::move(f), std::move(promise));
      },
      [SelfId = actor_id(this)](td::Result<RegisteredPayloadSenderGuard> R) {
        if (R.is_error()) {
          LOG(INFO) << "Failed to register request sender: " << R.move_as_error();
        }
        td::actor::send_closure(SelfId, &HttpRldpPayloadSender::registered_sender, R.move_as_ok());
      });

  class Cb : public ton::http::HttpPayload::Callback {
   public:
    Cb(td::actor::ActorId<HttpRldpPayloadSender> id, size_t watermark) : self_id_(id), watermark_(watermark) {
    }
    void run(size_t ready_bytes) override {
      if (!reached_ && ready_bytes >= watermark_) {
        reached_ = true;
        td::actor::send_closure(self_id_, &HttpRldpPayloadSender::try_answer_query, false);
      } else if (reached_ && ready_bytes < watermark_) {
        reached_ = false;
      }
    }
    void completed() override {
      td::actor::send_closure(self_id_, &HttpRldpPayloadSender::try_answer_query, false);
    }

   private:
    bool reached_ = false;
    td::actor::ActorId<HttpRldpPayloadSender> self_id_;
    size_t watermark_;
  };

  payload_->add_callback(
      std::make_unique<Cb>(actor_id(this), is_tunnel_ ? 1 : ton::http::HttpRequest::low_watermark()));

  alarm_timestamp() = td::Timestamp::in(is_tunnel_ ? 60.0 : 10.0);
}

void RldpTcpTunnel::start_up() {
  self_ = actor_id(this);
  td::actor::SchedulerContext::get()->get_poll().subscribe(fd_.get_poll_info().extract_pollable_fd(this),
                                                           td::PollFlags::ReadWrite());
  td::actor::send_closure(
      proxy_, &RldpHttpProxy::register_payload_sender, id_,
      [SelfId = actor_id(this)](ton::tl_object_ptr<ton::ton_api::http_getNextPayloadPart> f,
                                td::Promise<td::BufferSlice> promise) {
        td::actor::send_closure(SelfId, &RldpTcpTunnel::receive_query, std::move(f), std::move(promise));
      },
      [SelfId = actor_id(this)](td::Result<RegisteredPayloadSenderGuard> R) {
        if (R.is_error()) {
          LOG(INFO) << "Failed to register request sender: " << R.move_as_error();
        }
        td::actor::send_closure(SelfId, &RldpTcpTunnel::registered_sender, R.move_as_ok());
      });
  process();
}

int main(int argc, char *argv[]) {
  SET_VERBOSITY_LEVEL(verbosity_WARNING);

  td::set_default_failure_signal_handler().ensure();

  td::actor::ActorOwn<RldpHttpProxy> x;
  td::unique_ptr<td::LogInterface> logger_;
  SCOPE_EXIT {
    td::log_interface = td::default_log_interface;
  };

  auto add_local_host = [&](const std::string &local, const std::string &remote) -> td::Status {
    std::string host;
    std::vector<td::uint16> ports;
    auto p = local.find(':');
    if (p == std::string::npos) {
      host = local;
      ports = {80, 443};
    } else {
      host = local.substr(0, p);
      ++p;
      while (p < local.size()) {
        auto p2 = local.find(',', p);
        if (p2 == std::string::npos) {
          p2 = local.size();
        }
        try {
          ports.push_back((td::uint16)std::stoul(local.substr(p, p2 - p)));
        } catch (const std::logic_error &e) {
          return td::Status::Error(PSLICE() << "Invalid port: " << local.substr(p, p2 - p));
        }
        p = p2 + 1;
      }
    }
    for (td::uint16 port : ports) {
      std::string cur_remote = remote;
      if (cur_remote.find(':') == std::string::npos) {
        cur_remote += ':';
        cur_remote += std::to_string(port);
      }
      td::IPAddress addr;
      TRY_STATUS(addr.init_host_port(cur_remote));
      td::actor::send_closure(x, &RldpHttpProxy::set_local_host, host, port, addr);
    }
    return td::Status::OK();
  };

  td::OptionParser p;
  p.set_description(
      "A simple rldp-to-http and http-to-rldp proxy for running and accessing ton sites\n"
      "Example:\n\trldp-http-proxy -p 8080 -c 3333 -C ton-global.config.json\tRuns a local HTTP->RLDP proxy that "
      "accepts HTTP proxy queries at localhost:8080\n"
      "Example:\n\trldp-http-proxy -a <global-ip>:3333 -L example.ton -C ton-global.config.json\tRuns a local "
      "RLDP->HTTP proxy on UDP port <global-ip>:3333 that forwards all queries for http://example.ton to HTTP server "
      "at localhost:80\n");
  p.add_option('v', "verbosity", "set verbosity level", [&](td::Slice arg) {
    int v = VERBOSITY_NAME(FATAL) + (td::to_integer<int>(arg));
    SET_VERBOSITY_LEVEL(v);
  });
  p.add_option('V', "version", "shows rldp-http-proxy build information", [&]() {
    std::cout << "rldp-http-proxy build information: [ Commit: " << GitMetadata::CommitSHA1()
              << ", Date: " << GitMetadata::CommitDate() << "]\n";
    std::exit(0);
  });
  p.add_option('h', "help", "prints a help message", [&]() {
    char b[10240];
    td::StringBuilder sb(td::MutableSlice{b, 10000});
    sb << p;
    std::cout << sb.as_cslice().c_str();
    std::exit(2);
  });
  p.add_checked_option('p', "port", "sets http listening port", [&](td::Slice arg) -> td::Status {
    TRY_RESULT(port, td::to_integer_safe<td::uint16>(arg));
    td::actor::send_closure(x, &RldpHttpProxy::set_port, port);
    return td::Status::OK();
  });
  p.add_checked_option('a', "address", "local <ip>:<port> to use for adnl queries", [&](td::Slice arg) -> td::Status {
    td::IPAddress addr;
    TRY_STATUS(addr.init_host_port(arg.str()));
    td::actor::send_closure(x, &RldpHttpProxy::set_addr, addr);
    return td::Status::OK();
  });
  p.add_checked_option('A', "adnl", "server ADNL addr", [&](td::Slice arg) -> td::Status {
    TRY_RESULT(adnl, ton::adnl::AdnlNodeIdShort::parse(arg));
    td::actor::send_closure(x, &RldpHttpProxy::add_adnl_addr, adnl);
    return td::Status::OK();
  });
  p.add_checked_option('c', "client-port", "local <port> to use for client adnl queries",
                       [&](td::Slice arg) -> td::Status {
                         TRY_RESULT(port, td::to_integer_safe<td::uint16>(arg));
                         td::actor::send_closure(x, &RldpHttpProxy::set_client_port, port);
                         return td::Status::OK();
                       });
  p.add_option('C', "global-config", "global TON configuration file",
               [&](td::Slice arg) { td::actor::send_closure(x, &RldpHttpProxy::set_global_config, arg.str()); });
  p.add_checked_option('L', "local",
                       "<hosthame>:<ports>, hostname that will be proxied to localhost\n"
                       "<ports> is a comma-separated list of ports (may be omitted, default: 80, 443)\n",
                       [&](td::Slice arg) -> td::Status { return add_local_host(arg.str(), "127.0.0.1"); });
  p.add_option('D', "db", "db root",
               [&](td::Slice arg) { td::actor::send_closure(x, &RldpHttpProxy::set_db_root, arg.str()); });
  p.add_checked_option(
      'R', "remote",
      "<hostname>:<ports>@<ip>:<port>, indicates a hostname that will be proxied to remote server at <ip>:<port>\n"
      "<ports> is a comma-separated list of ports (may be omitted, default: 80,433)\n"
      "<port> is a remote port (may be omitted, default: same as host's port)",
      [&](td::Slice arg) -> td::Status {
        auto ch = arg.find('@');
        if (ch == td::Slice::npos) {
          return td::Status::Error("bad format for --remote");
        }
        return add_local_host(arg.substr(0, ch).str(), arg.substr(ch + 1).str());
      });
  p.add_option('d', "daemonize", "set SIGHUP", [&]() {
    td::set_signal_handler(td::SignalType::HangUp, [](int sig) {
#if TD_DARWIN || TD_LINUX
      close(0);
      setsid();
#endif
    }).ensure();
  });
  p.add_option('l', "logname", "log to file", [&](td::Slice fname) {
    logger_ = td::FileLog::create(fname.str()).move_as_ok();
    td::log_interface = logger_.get();
  });
  p.add_checked_option('S', "storage-gateway", "adnl address of ton storage gateway", [&](td::Slice arg) -> td::Status {
    TRY_RESULT(adnl, ton::adnl::AdnlNodeIdShort::parse(arg));
    td::actor::send_closure(x, &RldpHttpProxy::set_storage_gateway, adnl);
    return td::Status::OK();
  });
  p.add_checked_option('P', "proxy-all", "value=[YES|NO]. proxy all HTTP requests (default only *.ton and *.adnl)",
                       [&](td::Slice value) {
                         if (value == "YES" || value == "yes") {
                           td::actor::send_closure(x, &RldpHttpProxy::set_proxy_all, true);
                         } else if (value == "NO" || value == "no") {
                           td::actor::send_closure(x, &RldpHttpProxy::set_proxy_all, false);
                         } else {
                           return td::Status::Error("--proxy-all expected YES or NO");
                         }

                         return td::Status::OK();
                       });

  td::actor::Scheduler scheduler({7});

  scheduler.run_in_context([&] { x = td::actor::create_actor<RldpHttpProxy>("proxymain"); });

  scheduler.run_in_context([&] { p.run(argc, argv).ensure(); });
  scheduler.run_in_context([&] { td::actor::send_closure(x, &RldpHttpProxy::run); });
  while (scheduler.run(1)) {
  }

  return 0;
}