feat: boostrap hicn 22.02

The current patch provides several new features, improvements,
bug fixes and also complete rewrite of entire components.

- lib
The hicn packet parser has been improved with a new packet
format fully based on UDP. The TCP header is still temporarily
supported but the UDP header will replace completely the new hicn
packet format. Improvements have been made to make sure every
packet parsing operation is made via this library. The current
new header can be used as header between the payload and the
UDP header or as trailer in the UDP surplus area to be tested
when UDP options will start to be used.

- hicn-light
The portable packet forwarder has been completely rewritten from
scratch with the twofold objective to improve performance and
code size but  also to drop dependencies such as libparc which is
now removed by the current implementation.

- hicn control
the control library is the agent that is used to program the
packet forwarders via their binary API. This component has
benefited from significant improvements in terms of interaction
model which is now event driven and more robust to failures.

- VPP plugin has been updated to support VPP 22.02

- transport
Major improvement have been made to the RTC protocol, to the
support of IO modules and to the security sub system. Signed
manifests are the default data authenticity and integrity framework.
Confidentiality can be enabled by sharing the encryption key to the
prod/cons layer. The library has been tested with group key based
applications such as broadcast/multicast and real-time on-line
meetings with trusted server keys or MLS.

- testing
Unit testing has been introduced using GoogleTest. One third of
the code base is covered by unit testing with priority on
critical features. Functional testing has also been introduce
using Docker, linux bridging and Robot Framework to define
test with Less Code techniques to facilitate the extension
of the coverage.

Co-authored-by: Mauro Sardara <msardara@cisco.com>
Co-authored-by: Jordan Augé <jordan.auge+fdio@cisco.com>
Co-authored-by: Michele Papalini <micpapal@cisco.com>
Co-authored-by: Angelo Mantellini <manangel@cisco.com>
Co-authored-by: Jacques Samain <jsamain@cisco.com>
Co-authored-by: Olivier Roques <oroques+fdio@cisco.com>
Co-authored-by: Enrico Loparco <eloparco@cisco.com>
Co-authored-by: Giulio Grassi <gigrassi@cisco.com>

Change-Id: I75d0ef70f86d921e3ef503c99271216ff583c215
Signed-off-by: Luca Muscariello <muscariello@ieee.org>
Signed-off-by: Mauro Sardara <msardara@cisco.com>

10 files changed, 83 insertions, 773 deletions

diff --git a/libtransport/src/io_modules/forwarder/CMakeLists.txt b/libtransport/src/io_modules/forwarder/CMakeLists.txt
index a1d0c5db5..3922316d3 100644
--- a/libtransport/src/io_modules/forwarder/CMakeLists.txt
+++ b/libtransport/src/io_modules/forwarder/CMakeLists.txt
@@ -1,4 +1,4 @@
-# Copyright (c) 2021 Cisco and/or its affiliates.
+# Copyright (c) 2021-2022 Cisco and/or its affiliates.
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at:
@@ -17,8 +17,6 @@ list(APPEND MODULE_HEADER_FILES
   ${CMAKE_CURRENT_SOURCE_DIR}/errors.h
   ${CMAKE_CURRENT_SOURCE_DIR}/forwarder_module.h
   ${CMAKE_CURRENT_SOURCE_DIR}/forwarder.h
-  ${CMAKE_CURRENT_SOURCE_DIR}/udp_tunnel_listener.h
-  ${CMAKE_CURRENT_SOURCE_DIR}/udp_tunnel.h
   ${CMAKE_CURRENT_SOURCE_DIR}/global_counter.h
 )
 
@@ -26,16 +24,13 @@ list(APPEND MODULE_SOURCE_FILES
   ${CMAKE_CURRENT_SOURCE_DIR}/errors.cc
   ${CMAKE_CURRENT_SOURCE_DIR}/forwarder_module.cc
   ${CMAKE_CURRENT_SOURCE_DIR}/forwarder.cc
-  ${CMAKE_CURRENT_SOURCE_DIR}/udp_tunnel_listener.cc
-  ${CMAKE_CURRENT_SOURCE_DIR}/udp_tunnel.cc
 )
 
 build_module(forwarder_module
-    SHARED
     SOURCES ${MODULE_SOURCE_FILES}
     DEPENDS ${DEPENDENCIES}
     COMPONENT ${LIBTRANSPORT_COMPONENT}-io-modules
-    INCLUDE_DIRS ${LIBTRANSPORT_INCLUDE_DIRS} ${LIBTRANSPORT_INTERNAL_INCLUDE_DIRS}
+    INCLUDE_DIRS ${LIBTRANSPORT_INTERNAL_INCLUDE_DIRS} ${Libhicn_INCLUDE_DIRS}
     DEFINITIONS ${COMPILER_DEFINITIONS}
-    COMPILE_OPTIONS ${COMPILE_FLAGS}
+    COMPILE_OPTIONS ${COMPILER_OPTIONS}
 )
diff --git a/libtransport/src/io_modules/forwarder/errors.cc b/libtransport/src/io_modules/forwarder/errors.cc
index b5f131499..6e93d0453 100644
--- a/libtransport/src/io_modules/forwarder/errors.cc
+++ b/libtransport/src/io_modules/forwarder/errors.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 Cisco and/or its affiliates.
+ * Copyright (c) 2021 Cisco and/or its affiliates.
  */
 
 #include <io_modules/forwarder/errors.h>
diff --git a/libtransport/src/io_modules/forwarder/forwarder.cc b/libtransport/src/io_modules/forwarder/forwarder.cc
index 0546cb8b3..3ae5bf397 100644
--- a/libtransport/src/io_modules/forwarder/forwarder.cc
+++ b/libtransport/src/io_modules/forwarder/forwarder.cc
@@ -15,11 +15,11 @@
 
 #include <core/global_configuration.h>
 #include <core/local_connector.h>
+#include <core/udp_connector.h>
+#include <core/udp_listener.h>
 #include <glog/logging.h>
 #include <io_modules/forwarder/forwarder.h>
 #include <io_modules/forwarder/global_id_counter.h>
-#include <io_modules/forwarder/udp_tunnel.h>
-#include <io_modules/forwarder/udp_tunnel_listener.h>
 
 namespace transport {
 
@@ -89,11 +89,12 @@ void Forwarder::initConnectors() {
 Connector::Id Forwarder::registerLocalConnector(
     asio::io_service &io_service,
     Connector::PacketReceivedCallback &&receive_callback,
+    Connector::PacketSentCallback &&sent_callback,
     Connector::OnReconnectCallback &&reconnect_callback) {
   utils::SpinLock::Acquire locked(connector_lock_);
   auto id = GlobalCounter<Connector::Id>::getInstance().getNext();
   auto connector = std::make_shared<LocalConnector>(
-      io_service, receive_callback, nullptr, nullptr, reconnect_callback);
+      io_service, receive_callback, sent_callback, nullptr, reconnect_callback);
   connector->setConnectorId(id);
   local_connectors_.emplace(id, std::move(connector));
   return id;
@@ -105,6 +106,7 @@ Forwarder &Forwarder::deleteConnector(Connector::Id id) {
   if (it != local_connectors_.end()) {
     it->second->close();
     local_connectors_.erase(it);
+  } else {
   }
 
   return *this;
@@ -120,9 +122,9 @@ Connector::Ptr Forwarder::getConnector(Connector::Id id) {
   return nullptr;
 }
 
-void Forwarder::onPacketFromListener(Connector *connector,
-                                     utils::MemBuf &packet_buffer,
-                                     const std::error_code &ec) {
+void Forwarder::onPacketFromListener(
+    Connector *connector, const std::vector<utils::MemBuf::Ptr> &packets,
+    const std::error_code &ec) {
   // Create connector
   connector->setReceiveCallback(
       std::bind(&Forwarder::onPacketReceived, this, std::placeholders::_1,
@@ -135,37 +137,47 @@ void Forwarder::onPacketFromListener(Connector *connector,
     remote_connectors_.emplace(connector->getConnectorId(),
                                connector->shared_from_this());
   }
+
   // TODO Check if control packet or not. For the moment it is not.
-  onPacketReceived(connector, packet_buffer, ec);
+  onPacketReceived(connector, packets, ec);
 }
 
 void Forwarder::onPacketReceived(Connector *connector,
-                                 utils::MemBuf &packet_buffer,
+                                 const std::vector<utils::MemBuf::Ptr> &packets,
                                  const std::error_code &ec) {
-  // Figure out the type of packet we received
-  bool is_interest = Packet::isInterest(packet_buffer.data());
-
-  Packet *packet = nullptr;
-  if (is_interest) {
-    packet = static_cast<Interest *>(&packet_buffer);
-  } else {
-    packet = static_cast<ContentObject *>(&packet_buffer);
+  if (ec) {
+    LOG(ERROR) << "Error receiving packet: " << ec.message();
+    return;
   }
 
-  for (auto &c : local_connectors_) {
-    auto role = c.second->getRole();
-    auto is_producer = role == Connector::Role::PRODUCER;
-    if ((is_producer && is_interest) || (!is_producer && !is_interest)) {
-      c.second->send(*packet);
+  for (auto &packet_buffer_ptr : packets) {
+    auto &packet_buffer = *packet_buffer_ptr;
+
+    // Figure out the type of packet we received
+    bool is_interest = Packet::isInterest(packet_buffer.data());
+
+    Packet *packet = nullptr;
+    if (is_interest) {
+      packet = static_cast<Interest *>(&packet_buffer);
     } else {
-      LOG(ERROR) << "Error sending packet to local connector. is_interest = "
-                 << is_interest << " - is_producer = " << is_producer;
+      packet = static_cast<ContentObject *>(&packet_buffer);
+    }
+
+    for (auto &c : local_connectors_) {
+      auto role = c.second->getRole();
+      auto is_producer = role == Connector::Role::PRODUCER;
+      if ((is_producer && is_interest) || (!is_producer && !is_interest)) {
+        c.second->send(*packet);
+      } else {
+        LOG(ERROR) << "Error sending packet to local connector. is_interest = "
+                   << is_interest << " - is_producer = " << is_producer;
+      }
     }
-  }
 
-  // PCS Lookup + FIB lookup. Skip for now
+    // PCS Lookup + FIB lookup. Skip for now
 
-  // Forward packet to local connectors
+    // Forward packet to local connectors
+  }
 }
 
 void Forwarder::send(Packet &packet) {
diff --git a/libtransport/src/io_modules/forwarder/forwarder.h b/libtransport/src/io_modules/forwarder/forwarder.h
index 5b564bb5e..38b4260b3 100644
--- a/libtransport/src/io_modules/forwarder/forwarder.h
+++ b/libtransport/src/io_modules/forwarder/forwarder.h
@@ -15,13 +15,13 @@
 
 #pragma once
 
+#include <core/udp_listener.h>
 #include <hicn/transport/core/io_module.h>
 #include <hicn/transport/core/prefix.h>
 #include <hicn/transport/utils/event_thread.h>
 #include <hicn/transport/utils/singleton.h>
 #include <hicn/transport/utils/spinlock.h>
 #include <io_modules/forwarder/configuration.h>
-#include <io_modules/forwarder/udp_tunnel_listener.h>
 
 #include <atomic>
 #include <libconfig.h++>
@@ -31,9 +31,8 @@ namespace transport {
 
 namespace core {
 
-class Forwarder : public utils::Singleton<Forwarder> {
+class Forwarder {
   static constexpr char forwarder_config_section[] = "forwarder";
-  friend class utils::Singleton<Forwarder>;
 
  public:
   Forwarder();
@@ -47,6 +46,7 @@ class Forwarder : public utils::Singleton<Forwarder> {
   Connector::Id registerLocalConnector(
       asio::io_service &io_service,
       Connector::PacketReceivedCallback &&receive_callback,
+      Connector::PacketSentCallback &&sent_callback,
       Connector::OnReconnectCallback &&reconnect_callback);
 
   Forwarder &deleteConnector(Connector::Id id);
@@ -58,9 +58,11 @@ class Forwarder : public utils::Singleton<Forwarder> {
   void stop();
 
  private:
-  void onPacketFromListener(Connector *connector, utils::MemBuf &packet_buffer,
+  void onPacketFromListener(Connector *connector,
+                            const std::vector<utils::MemBuf::Ptr> &packets,
                             const std::error_code &ec);
-  void onPacketReceived(Connector *connector, utils::MemBuf &packet_buffer,
+  void onPacketReceived(Connector *connector,
+                        const std::vector<utils::MemBuf::Ptr> &packets,
                         const std::error_code &ec);
   void onPacketSent(Connector *connector, const std::error_code &ec);
   void onConnectorClosed(Connector *connector);
@@ -86,5 +88,20 @@ class Forwarder : public utils::Singleton<Forwarder> {
   Configuration config_;
 };
 
+class ForwarderGlobal : public ::utils::Singleton<ForwarderGlobal> {
+  friend class utils::Singleton<ForwarderGlobal>;
+
+ public:
+  ~ForwarderGlobal() {}
+  std::shared_ptr<Forwarder> &getReference() { return forwarder_; }
+
+ private:
+  ForwarderGlobal() : forwarder_(std::make_shared<Forwarder>()) {}
+
+ private:
+  std::shared_ptr<Forwarder> forwarder_;
+};
+
 }  // namespace core
-}  // namespace transport
\ No newline at end of file
+
+}  // namespace transport
diff --git a/libtransport/src/io_modules/forwarder/forwarder_module.cc b/libtransport/src/io_modules/forwarder/forwarder_module.cc
index 4f95b9ca0..0ced84ab4 100644
--- a/libtransport/src/io_modules/forwarder/forwarder_module.cc
+++ b/libtransport/src/io_modules/forwarder/forwarder_module.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2020 Cisco and/or its affiliates.
+ * Copyright (c) 2021 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -25,11 +25,10 @@ ForwarderModule::ForwarderModule()
     : IoModule(),
       name_(""),
       connector_id_(Connector::invalid_connector),
-      forwarder_(Forwarder::getInstance()) {}
+      forwarder_ptr_(ForwarderGlobal::getInstance().getReference()),
+      forwarder_(*forwarder_ptr_) {}
 
-ForwarderModule::~ForwarderModule() {
-  forwarder_.deleteConnector(connector_id_);
-}
+ForwarderModule::~ForwarderModule() {}
 
 bool ForwarderModule::isConnected() { return true; }
 
@@ -42,7 +41,7 @@ void ForwarderModule::send(Packet &packet) {
   // local_faces_.at(1 - local_id_).onPacket(packet);
 }
 
-void ForwarderModule::send(const uint8_t *packet, std::size_t len) {
+void ForwarderModule::send(const utils::MemBuf::Ptr &buffer) {
   // not supported
   throw errors::NotImplementedException();
 }
@@ -58,11 +57,13 @@ void ForwarderModule::closeConnection() {
 }
 
 void ForwarderModule::init(Connector::PacketReceivedCallback &&receive_callback,
+                           Connector::PacketSentCallback &&sent_callback,
                            Connector::OnReconnectCallback &&reconnect_callback,
                            asio::io_service &io_service,
                            const std::string &app_name) {
   connector_id_ = forwarder_.registerLocalConnector(
-      io_service, std::move(receive_callback), std::move(reconnect_callback));
+      io_service, std::move(receive_callback), std::move(sent_callback),
+      std::move(reconnect_callback));
   name_ = app_name;
 }
 
@@ -78,7 +79,9 @@ void ForwarderModule::connect(bool is_consumer) {
 
 std::uint32_t ForwarderModule::getMtu() { return interface_mtu; }
 
-bool ForwarderModule::isControlMessage(const uint8_t *message) { return false; }
+bool ForwarderModule::isControlMessage(utils::MemBuf &packet_buffer) {
+  return false;
+}
 
 extern "C" IoModule *create_module(void) { return new ForwarderModule(); }
 
diff --git a/libtransport/src/io_modules/forwarder/forwarder_module.h b/libtransport/src/io_modules/forwarder/forwarder_module.h
index 58bfb7996..52a12b67e 100644
--- a/libtransport/src/io_modules/forwarder/forwarder_module.h
+++ b/libtransport/src/io_modules/forwarder/forwarder_module.h
@@ -38,11 +38,12 @@ class ForwarderModule : public IoModule {
   void connect(bool is_consumer) override;
 
   void send(Packet &packet) override;
-  void send(const uint8_t *packet, std::size_t len) override;
+  void send(const utils::MemBuf::Ptr &buffer) override;
 
   bool isConnected() override;
 
   void init(Connector::PacketReceivedCallback &&receive_callback,
+            Connector::PacketSentCallback &&sent_callback,
             Connector::OnReconnectCallback &&reconnect_callback,
             asio::io_service &io_service,
             const std::string &app_name = "Libtransport") override;
@@ -51,15 +52,19 @@ class ForwarderModule : public IoModule {
 
   std::uint32_t getMtu() override;
 
-  bool isControlMessage(const uint8_t *message) override;
+  bool isControlMessage(utils::MemBuf &packet_buffer) override;
 
   void processControlMessageReply(utils::MemBuf &packet_buffer) override;
 
   void closeConnection() override;
 
  private:
+  static void initForwarder();
+
+ private:
   std::string name_;
   Connector::Id connector_id_;
+  std::shared_ptr<Forwarder> forwarder_ptr_;
   Forwarder &forwarder_;
 };
 
diff --git a/libtransport/src/io_modules/forwarder/udp_tunnel.cc b/libtransport/src/io_modules/forwarder/udp_tunnel.cc
deleted file mode 100644
index bf6a69b92..000000000
--- a/libtransport/src/io_modules/forwarder/udp_tunnel.cc
+++ /dev/null
@@ -1,290 +0,0 @@
-/*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
- */
-
-#include <glog/logging.h>
-#include <hicn/transport/utils/branch_prediction.h>
-#include <io_modules/forwarder/errors.h>
-#include <io_modules/forwarder/udp_tunnel.h>
-
-#include <iostream>
-#include <thread>
-#include <vector>
-
-namespace transport {
-namespace core {
-
-UdpTunnelConnector::~UdpTunnelConnector() {}
-
-void UdpTunnelConnector::connect(const std::string &hostname, uint16_t port,
-                                 const std::string &bind_address,
-                                 uint16_t bind_port) {
-  if (state_ == State::CLOSED) {
-    state_ = State::CONNECTING;
-    endpoint_iterator_ = resolver_.resolve({hostname, std::to_string(port)});
-    remote_endpoint_send_ = *endpoint_iterator_;
-    socket_->open(remote_endpoint_send_.protocol());
-
-    if (!bind_address.empty() && bind_port != 0) {
-      using namespace asio::ip;
-      socket_->bind(
-          udp::endpoint(address::from_string(bind_address), bind_port));
-    }
-
-    state_ = State::CONNECTED;
-
-    remote_endpoint_ = Endpoint(remote_endpoint_send_);
-    local_endpoint_ = Endpoint(socket_->local_endpoint());
-
-    doRecvPacket();
-
-#ifdef LINUX
-    send_timer_.expires_from_now(std::chrono::microseconds(50));
-    send_timer_.async_wait(std::bind(&UdpTunnelConnector::writeHandler, this,
-                                     std::placeholders::_1));
-#endif
-  }
-}
-
-void UdpTunnelConnector::send(Packet &packet) {
-  strand_->post([this, pkt{packet.shared_from_this()}]() {
-    bool write_in_progress = !output_buffer_.empty();
-    output_buffer_.push_back(std::move(pkt));
-    if (TRANSPORT_EXPECT_TRUE(state_ == State::CONNECTED)) {
-      if (!write_in_progress) {
-        doSendPacket();
-      }
-    } else {
-      data_available_ = true;
-    }
-  });
-}
-
-void UdpTunnelConnector::send(const uint8_t *packet, std::size_t len) {}
-
-void UdpTunnelConnector::close() {
-  DLOG_IF(INFO, VLOG_IS_ON(2)) << "UDPTunnelConnector::close";
-  state_ = State::CLOSED;
-  bool is_socket_owned = socket_.use_count() == 1;
-  if (is_socket_owned) {
-    io_service_.dispatch([this]() {
-      this->socket_->close();
-      // on_close_callback_(shared_from_this());
-    });
-  }
-}
-
-void UdpTunnelConnector::doSendPacket() {
-#ifdef LINUX
-  send_timer_.expires_from_now(std::chrono::microseconds(50));
-  send_timer_.async_wait(std::bind(&UdpTunnelConnector::writeHandler, this,
-                                   std::placeholders::_1));
-#else
-  auto packet = output_buffer_.front().get();
-  auto array = std::vector<asio::const_buffer>();
-
-  const ::utils::MemBuf *current = packet;
-  do {
-    array.push_back(asio::const_buffer(current->data(), current->length()));
-    current = current->next();
-  } while (current != packet);
-
-  socket_->async_send_to(
-      std::move(array), remote_endpoint_send_,
-      strand_->wrap([this](std::error_code ec, std::size_t length) {
-        if (TRANSPORT_EXPECT_TRUE(!ec)) {
-          sent_callback_(this, make_error_code(forwarder_error::success));
-        } else if (ec.value() ==
-                   static_cast<int>(std::errc::operation_canceled)) {
-          // The connection has been closed by the application.
-          return;
-        } else {
-          sendFailed();
-          sent_callback_(this, ec);
-        }
-
-        output_buffer_.pop_front();
-        if (!output_buffer_.empty()) {
-          doSendPacket();
-        }
-      }));
-#endif
-}
-
-#ifdef LINUX
-void UdpTunnelConnector::writeHandler(std::error_code ec) {
-  if (TRANSPORT_EXPECT_FALSE(state_ != State::CONNECTED)) {
-    return;
-  }
-
-  auto len = std::min(output_buffer_.size(), std::size_t(Connector::max_burst));
-
-  if (len) {
-    int m = 0;
-    for (auto &p : output_buffer_) {
-      auto packet = p.get();
-      ::utils::MemBuf *current = packet;
-      int b = 0;
-      do {
-        // array.push_back(asio::const_buffer(current->data(),
-        // current->length()));
-        tx_iovecs_[m][b].iov_base = current->writableData();
-        tx_iovecs_[m][b].iov_len = current->length();
-        current = current->next();
-        b++;
-      } while (current != packet);
-
-      tx_msgs_[m].msg_hdr.msg_iov = tx_iovecs_[m];
-      tx_msgs_[m].msg_hdr.msg_iovlen = b;
-      tx_msgs_[m].msg_hdr.msg_name = remote_endpoint_send_.data();
-      tx_msgs_[m].msg_hdr.msg_namelen = remote_endpoint_send_.size();
-      m++;
-
-      if (--len == 0) {
-        break;
-      }
-    }
-
-    int retval = sendmmsg(socket_->native_handle(), tx_msgs_, m, MSG_DONTWAIT);
-    if (retval > 0) {
-      while (retval--) {
-        output_buffer_.pop_front();
-      }
-    } else if (retval != EWOULDBLOCK && retval != EAGAIN) {
-      LOG(ERROR) << "Error sending messages! " << strerror(errno)
-                 << " << retval";
-      return;
-    }
-  }
-
-  if (!output_buffer_.empty()) {
-    send_timer_.expires_from_now(std::chrono::microseconds(50));
-    send_timer_.async_wait(std::bind(&UdpTunnelConnector::writeHandler, this,
-                                     std::placeholders::_1));
-  }
-}
-
-void UdpTunnelConnector::readHandler(std::error_code ec) {
-  DLOG_IF(INFO, VLOG_IS_ON(3)) << "UdpTunnelConnector receive packet";
-
-  if (TRANSPORT_EXPECT_TRUE(!ec)) {
-    if (TRANSPORT_EXPECT_TRUE(state_ == State::CONNECTED)) {
-      if (current_position_ == 0) {
-        for (int i = 0; i < max_burst; i++) {
-          auto read_buffer = getRawBuffer();
-          rx_iovecs_[i][0].iov_base = read_buffer.first;
-          rx_iovecs_[i][0].iov_len = read_buffer.second;
-          rx_msgs_[i].msg_hdr.msg_iov = rx_iovecs_[i];
-          rx_msgs_[i].msg_hdr.msg_iovlen = 1;
-        }
-      }
-
-      int res = recvmmsg(socket_->native_handle(), rx_msgs_ + current_position_,
-                         max_burst - current_position_, MSG_DONTWAIT, nullptr);
-      if (res < 0) {
-        LOG(ERROR) << "Error receiving messages! " << strerror(errno) << " "
-                   << res;
-        return;
-      }
-
-      for (int i = 0; i < res; i++) {
-        auto packet = getPacketFromBuffer(
-            reinterpret_cast<uint8_t *>(
-                rx_msgs_[current_position_].msg_hdr.msg_iov[0].iov_base),
-            rx_msgs_[current_position_].msg_len);
-        receiveSuccess(*packet);
-        receive_callback_(this, *packet,
-                          make_error_code(forwarder_error::success));
-        ++current_position_;
-      }
-
-      doRecvPacket();
-    } else {
-      LOG(ERROR)
-          << "Error in UDP: Receiving packets from a not connected socket.";
-    }
-  } else if (ec.value() == static_cast<int>(std::errc::operation_canceled)) {
-    LOG(ERROR) << "The connection has been closed by the application.";
-    return;
-  } else {
-    if (TRANSPORT_EXPECT_TRUE(state_ == State::CONNECTED)) {
-      // receive_callback_(this, *read_msg_, ec);
-      LOG(ERROR) << "Error in UDP connector: " << ec.value() << " "
-                 << ec.message();
-    } else {
-      LOG(ERROR) << "Error in connector while not connected. " << ec.value()
-                 << " " << ec.message();
-    }
-  }
-}
-#endif
-
-void UdpTunnelConnector::doRecvPacket() {
-#ifdef LINUX
-  if (state_ == State::CONNECTED) {
-#if ((ASIO_VERSION / 100 % 1000) < 11)
-    socket_->async_receive(asio::null_buffers(),
-#else
-    socket_->async_wait(asio::ip::tcp::socket::wait_read,
-#endif
-                           std::bind(&UdpTunnelConnector::readHandler, this,
-                                     std::placeholders::_1));
-  }
-#else
-  DLOG_IF(INFO, VLOG_IS_ON(3)) << "UdpTunnelConnector receive packet";
-  read_msg_ = getRawBuffer();
-  socket_->async_receive_from(
-      asio::buffer(read_msg_.first, read_msg_.second), remote_endpoint_recv_,
-      [this](std::error_code ec, std::size_t length) {
-        DLOG_IF(INFO, VLOG_IS_ON(3))
-            << "UdpTunnelConnector received packet length=" << length;
-        if (TRANSPORT_EXPECT_TRUE(!ec)) {
-          if (TRANSPORT_EXPECT_TRUE(state_ == State::CONNECTED)) {
-            auto packet = getPacketFromBuffer(read_msg_.first, length);
-            receiveSuccess(*packet);
-            receive_callback_(this, *packet,
-                              make_error_code(forwarder_error::success));
-            doRecvPacket();
-          } else {
-            LOG(ERROR) << "Error in UDP: Receiving packets from a not "
-                          "connected socket.";
-          }
-        } else if (ec.value() ==
-                   static_cast<int>(std::errc::operation_canceled)) {
-          LOG(ERROR) << "The connection has been closed by the application.";
-          return;
-        } else {
-          if (TRANSPORT_EXPECT_TRUE(state_ == State::CONNECTED)) {
-            LOG(ERROR) << "Error in UDP connector: " << ec.value()
-                       << ec.message();
-          } else {
-            LOG(ERROR) << "Error while not connected";
-          }
-        }
-      });
-#endif
-}
-
-void UdpTunnelConnector::doConnect() {
-  asio::async_connect(
-      *socket_, endpoint_iterator_,
-      [this](std::error_code ec, asio::ip::udp::resolver::iterator) {
-        if (!ec) {
-          state_ = State::CONNECTED;
-          doRecvPacket();
-
-          if (data_available_) {
-            data_available_ = false;
-            doSendPacket();
-          }
-        } else {
-          LOG(ERROR) << "UDP Connection failed!!!";
-          timer_.expires_from_now(std::chrono::milliseconds(500));
-          timer_.async_wait(std::bind(&UdpTunnelConnector::doConnect, this));
-        }
-      });
-}
-
-}  // namespace core
-
-}  // namespace transport
diff --git a/libtransport/src/io_modules/forwarder/udp_tunnel.h b/libtransport/src/io_modules/forwarder/udp_tunnel.h
deleted file mode 100644
index 4f044f93f..000000000
--- a/libtransport/src/io_modules/forwarder/udp_tunnel.h
+++ /dev/null
@@ -1,146 +0,0 @@
-/*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
- */
-
-#pragma once
-
-#include <hicn/transport/core/asio_wrapper.h>
-#include <hicn/transport/core/connector.h>
-#include <hicn/transport/portability/platform.h>
-#include <io_modules/forwarder/errors.h>
-
-#include <iostream>
-#include <memory>
-
-namespace transport {
-namespace core {
-
-class UdpTunnelListener;
-
-class UdpTunnelConnector : public Connector {
-  friend class UdpTunnelListener;
-
- public:
-  template <typename ReceiveCallback, typename SentCallback, typename OnClose,
-            typename OnReconnect>
-  UdpTunnelConnector(asio::io_service &io_service,
-                     ReceiveCallback &&receive_callback,
-                     SentCallback &&packet_sent, OnClose &&on_close_callback,
-                     OnReconnect &&on_reconnect)
-      : Connector(receive_callback, packet_sent, on_close_callback,
-                  on_reconnect),
-        io_service_(io_service),
-        strand_(std::make_shared<asio::io_service::strand>(io_service_)),
-        socket_(std::make_shared<asio::ip::udp::socket>(io_service_)),
-        resolver_(io_service_),
-        timer_(io_service_),
-#ifdef LINUX
-        send_timer_(io_service_),
-        tx_iovecs_{0},
-        tx_msgs_{0},
-        rx_iovecs_{0},
-        rx_msgs_{0},
-        current_position_(0),
-#else
-        read_msg_(nullptr, 0),
-#endif
-        data_available_(false) {
-  }
-
-  template <typename ReceiveCallback, typename SentCallback, typename OnClose,
-            typename OnReconnect, typename EndpointType>
-  UdpTunnelConnector(std::shared_ptr<asio::ip::udp::socket> &socket,
-                     std::shared_ptr<asio::io_service::strand> &strand,
-                     ReceiveCallback &&receive_callback,
-                     SentCallback &&packet_sent, OnClose &&on_close_callback,
-                     OnReconnect &&on_reconnect, EndpointType &&remote_endpoint)
-      : Connector(receive_callback, packet_sent, on_close_callback,
-                  on_reconnect),
-#if ((ASIO_VERSION / 100 % 1000) < 12)
-        io_service_(socket->get_io_service()),
-#else
-        io_service_((asio::io_context &)(socket->get_executor().context())),
-#endif
-        strand_(strand),
-        socket_(socket),
-        resolver_(io_service_),
-        remote_endpoint_send_(std::forward<EndpointType &&>(remote_endpoint)),
-        timer_(io_service_),
-#ifdef LINUX
-        send_timer_(io_service_),
-        tx_iovecs_{0},
-        tx_msgs_{0},
-        rx_iovecs_{0},
-        rx_msgs_{0},
-        current_position_(0),
-#else
-        read_msg_(nullptr, 0),
-#endif
-        data_available_(false) {
-    if (socket_->is_open()) {
-      state_ = State::CONNECTED;
-      remote_endpoint_ = Endpoint(remote_endpoint_send_);
-      local_endpoint_ = socket_->local_endpoint();
-    }
-  }
-
-  ~UdpTunnelConnector() override;
-
-  void send(Packet &packet) override;
-
-  void send(const uint8_t *packet, std::size_t len) override;
-
-  void close() override;
-
-  void connect(const std::string &hostname, std::uint16_t port,
-               const std::string &bind_address = "",
-               std::uint16_t bind_port = 0);
-
-  auto shared_from_this() { return utils::shared_from(this); }
-
- private:
-  void doConnect();
-  void doRecvPacket();
-
-  void doRecvPacket(utils::MemBuf &buffer) {
-    receive_callback_(this, buffer, make_error_code(forwarder_error::success));
-  }
-
-#ifdef LINUX
-  void readHandler(std::error_code ec);
-  void writeHandler(std::error_code ec);
-#endif
-
-  void setConnected() { state_ = State::CONNECTED; }
-
-  void doSendPacket();
-  void doClose();
-
- private:
-  asio::io_service &io_service_;
-  std::shared_ptr<asio::io_service::strand> strand_;
-  std::shared_ptr<asio::ip::udp::socket> socket_;
-  asio::ip::udp::resolver resolver_;
-  asio::ip::udp::resolver::iterator endpoint_iterator_;
-  asio::ip::udp::endpoint remote_endpoint_send_;
-  asio::ip::udp::endpoint remote_endpoint_recv_;
-
-  asio::steady_timer timer_;
-
-#ifdef LINUX
-  asio::steady_timer send_timer_;
-  struct iovec tx_iovecs_[max_burst][8];
-  struct mmsghdr tx_msgs_[max_burst];
-  struct iovec rx_iovecs_[max_burst][8];
-  struct mmsghdr rx_msgs_[max_burst];
-  std::uint8_t current_position_;
-#else
-  std::pair<uint8_t *, std::size_t> read_msg_;
-#endif
-
-  bool data_available_;
-};
-
-}  // namespace core
-
-}  // namespace transport
diff --git a/libtransport/src/io_modules/forwarder/udp_tunnel_listener.cc b/libtransport/src/io_modules/forwarder/udp_tunnel_listener.cc
deleted file mode 100644
index d047cc568..000000000
--- a/libtransport/src/io_modules/forwarder/udp_tunnel_listener.cc
+++ /dev/null
@@ -1,177 +0,0 @@
-/*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
- */
-
-#include <glog/logging.h>
-#include <hicn/transport/utils/hash.h>
-#include <io_modules/forwarder/udp_tunnel.h>
-#include <io_modules/forwarder/udp_tunnel_listener.h>
-
-#ifndef LINUX
-namespace std {
-size_t hash<asio::ip::udp::endpoint>::operator()(
-    const asio::ip::udp::endpoint &endpoint) const {
-  auto hash_ip = endpoint.address().is_v4()
-                     ? endpoint.address().to_v4().to_ulong()
-                     : utils::hash::fnv32_buf(
-                           endpoint.address().to_v6().to_bytes().data(), 16);
-  uint16_t port = endpoint.port();
-  return utils::hash::fnv32_buf(&port, 2, hash_ip);
-}
-}  // namespace std
-#endif
-
-namespace transport {
-namespace core {
-
-UdpTunnelListener::~UdpTunnelListener() {}
-
-void UdpTunnelListener::close() {
-  strand_->post([this]() {
-    if (socket_->is_open()) {
-      socket_->close();
-    }
-  });
-}
-
-#ifdef LINUX
-void UdpTunnelListener::readHandler(std::error_code ec) {
-  DLOG_IF(INFO, VLOG_IS_ON(3)) << "UdpTunnelConnector receive packet";
-
-  if (TRANSPORT_EXPECT_TRUE(!ec)) {
-    if (current_position_ == 0) {
-      for (int i = 0; i < Connector::max_burst; i++) {
-        auto read_buffer = Connector::getRawBuffer();
-        iovecs_[i][0].iov_base = read_buffer.first;
-        iovecs_[i][0].iov_len = read_buffer.second;
-        msgs_[i].msg_hdr.msg_iov = iovecs_[i];
-        msgs_[i].msg_hdr.msg_iovlen = 1;
-        msgs_[i].msg_hdr.msg_name = &remote_endpoints_[i];
-        msgs_[i].msg_hdr.msg_namelen = sizeof(remote_endpoints_[i]);
-      }
-    }
-
-    int res = recvmmsg(socket_->native_handle(), msgs_ + current_position_,
-                       Connector::max_burst - current_position_, MSG_DONTWAIT,
-                       nullptr);
-    if (res < 0) {
-      LOG(ERROR) << "Error in  recvmmsg.";
-      return;
-    }
-
-    for (int i = 0; i < res; i++) {
-      auto packet = Connector::getPacketFromBuffer(
-          reinterpret_cast<uint8_t *>(
-              msgs_[current_position_].msg_hdr.msg_iov[0].iov_base),
-          msgs_[current_position_].msg_len);
-      auto connector_id =
-          utils::hash::fnv64_buf(msgs_[current_position_].msg_hdr.msg_name,
-                                 msgs_[current_position_].msg_hdr.msg_namelen);
-
-      auto connector = connectors_.find(connector_id);
-      if (connector == connectors_.end()) {
-        // Create new connector corresponding to new client
-
-        /*
-         * Get the remote endpoint for this particular message
-         */
-        using namespace asio::ip;
-        if (local_endpoint_.address().is_v4()) {
-          auto addr = reinterpret_cast<struct sockaddr_in *>(
-              &remote_endpoints_[current_position_]);
-          address_v4::bytes_type address_bytes;
-          std::copy_n(reinterpret_cast<uint8_t *>(&addr->sin_addr),
-                      address_bytes.size(), address_bytes.begin());
-          address_v4 address(address_bytes);
-          remote_endpoint_ = udp::endpoint(address, ntohs(addr->sin_port));
-        } else {
-          auto addr = reinterpret_cast<struct sockaddr_in6 *>(
-              &remote_endpoints_[current_position_]);
-          address_v6::bytes_type address_bytes;
-          std::copy_n(reinterpret_cast<uint8_t *>(&addr->sin6_addr),
-                      address_bytes.size(), address_bytes.begin());
-          address_v6 address(address_bytes);
-          remote_endpoint_ = udp::endpoint(address, ntohs(addr->sin6_port));
-        }
-
-        /**
-         * Create new connector sharing the same socket of this listener.
-         */
-        auto ret = connectors_.emplace(
-            connector_id,
-            std::make_shared<UdpTunnelConnector>(
-                socket_, strand_, receive_callback_,
-                [](Connector *, const std::error_code &) {}, [](Connector *) {},
-                [](Connector *) {}, std::move(remote_endpoint_)));
-        connector = ret.first;
-        connector->second->setConnectorId(connector_id);
-      }
-
-      /**
-       * Use connector callback to process incoming message.
-       */
-      UdpTunnelConnector *c =
-          dynamic_cast<UdpTunnelConnector *>(connector->second.get());
-      c->doRecvPacket(*packet);
-
-      ++current_position_;
-    }
-
-    doRecvPacket();
-  } else if (ec.value() == static_cast<int>(std::errc::operation_canceled)) {
-    LOG(ERROR) << "The connection has been closed by the application.";
-    return;
-  } else {
-    LOG(ERROR) << ec.value() << " " << ec.message();
-  }
-}
-#endif
-
-void UdpTunnelListener::doRecvPacket() {
-#ifdef LINUX
-#if ((ASIO_VERSION / 100 % 1000) < 11)
-  socket_->async_receive(
-      asio::null_buffers(),
-#else
-  socket_->async_wait(
-      asio::ip::tcp::socket::wait_read,
-#endif
-      std::bind(&UdpTunnelListener::readHandler, this, std::placeholders::_1));
-#else
-  read_msg_ = Connector::getRawBuffer();
-  socket_->async_receive_from(
-      asio::buffer(read_msg_.first, read_msg_.second), remote_endpoint_,
-      [this](std::error_code ec, std::size_t length) {
-        if (TRANSPORT_EXPECT_TRUE(!ec)) {
-          auto packet = Connector::getPacketFromBuffer(read_msg_.first, length);
-          auto connector_id =
-              std::hash<asio::ip::udp::endpoint>{}(remote_endpoint_);
-          auto connector = connectors_.find(connector_id);
-          if (connector == connectors_.end()) {
-            // Create new connector corresponding to new client
-            auto ret = connectors_.emplace(
-                connector_id, std::make_shared<UdpTunnelConnector>(
-                                  socket_, strand_, receive_callback_,
-                                  [](Connector *, const std::error_code &) {},
-                                  [](Connector *) {}, [](Connector *) {},
-                                  std::move(remote_endpoint_)));
-            connector = ret.first;
-            connector->second->setConnectorId(connector_id);
-          }
-
-          UdpTunnelConnector *c =
-              dynamic_cast<UdpTunnelConnector *>(connector->second.get());
-          c->doRecvPacket(*packet);
-          doRecvPacket();
-        } else if (ec.value() ==
-                   static_cast<int>(std::errc::operation_canceled)) {
-          LOG(ERROR) << "The connection has been closed by the application.";
-          return;
-        } else {
-          LOG(ERROR) << ec.value() << " " << ec.message();
-        }
-      });
-#endif
-}
-}  // namespace core
-}  // namespace transport
\ No newline at end of file
diff --git a/libtransport/src/io_modules/forwarder/udp_tunnel_listener.h b/libtransport/src/io_modules/forwarder/udp_tunnel_listener.h
deleted file mode 100644
index 5d197dcb0..000000000
--- a/libtransport/src/io_modules/forwarder/udp_tunnel_listener.h
+++ /dev/null
@@ -1,109 +0,0 @@
-/*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
- */
-
-#pragma once
-
-#include <hicn/transport/core/asio_wrapper.h>
-#include <hicn/transport/core/connector.h>
-#include <hicn/transport/portability/platform.h>
-
-#include <unordered_map>
-
-namespace std {
-template <>
-struct hash<asio::ip::udp::endpoint> {
-  size_t operator()(const asio::ip::udp::endpoint &endpoint) const;
-};
-}  // namespace std
-
-namespace transport {
-namespace core {
-
-class UdpTunnelListener
-    : public std::enable_shared_from_this<UdpTunnelListener> {
-  using PacketReceivedCallback = Connector::PacketReceivedCallback;
-  using EndpointId = std::pair<uint32_t, uint16_t>;
-
-  static constexpr uint16_t default_port = 5004;
-
- public:
-  using Ptr = std::shared_ptr<UdpTunnelListener>;
-
-  template <typename ReceiveCallback>
-  UdpTunnelListener(asio::io_service &io_service,
-                    ReceiveCallback &&receive_callback,
-                    asio::ip::udp::endpoint endpoint = asio::ip::udp::endpoint(
-                        asio::ip::udp::v4(), default_port))
-      : io_service_(io_service),
-        strand_(std::make_shared<asio::io_service::strand>(io_service_)),
-        socket_(std::make_shared<asio::ip::udp::socket>(io_service_,
-                                                        endpoint.protocol())),
-        local_endpoint_(endpoint),
-        receive_callback_(std::forward<ReceiveCallback &&>(receive_callback)),
-#ifndef LINUX
-        read_msg_(nullptr, 0)
-#else
-        iovecs_{0},
-        msgs_{0},
-        current_position_(0)
-#endif
-  {
-    if (endpoint.protocol() == asio::ip::udp::v6()) {
-      std::error_code ec;
-      socket_->set_option(asio::ip::v6_only(false), ec);
-      // Call succeeds only on dual stack systems.
-    }
-    socket_->bind(local_endpoint_);
-    io_service_.post(std::bind(&UdpTunnelListener::doRecvPacket, this));
-  }
-
-  ~UdpTunnelListener();
-
-  void close();
-
-  int deleteConnector(Connector *connector) {
-    return connectors_.erase(connector->getConnectorId());
-  }
-
-  template <typename ReceiveCallback>
-  void setReceiveCallback(ReceiveCallback &&callback) {
-    receive_callback_ = std::forward<ReceiveCallback &&>(callback);
-  }
-
-  Connector *findConnector(Connector::Id connId) {
-    auto it = connectors_.find(connId);
-    if (it != connectors_.end()) {
-      return it->second.get();
-    }
-
-    return nullptr;
-  }
-
- private:
-  void doRecvPacket();
-
-  void readHandler(std::error_code ec);
-
-  asio::io_service &io_service_;
-  std::shared_ptr<asio::io_service::strand> strand_;
-  std::shared_ptr<asio::ip::udp::socket> socket_;
-  asio::ip::udp::endpoint local_endpoint_;
-  asio::ip::udp::endpoint remote_endpoint_;
-  std::unordered_map<Connector::Id, std::shared_ptr<Connector>> connectors_;
-
-  PacketReceivedCallback receive_callback_;
-
-#ifdef LINUX
-  struct iovec iovecs_[Connector::max_burst][8];
-  struct mmsghdr msgs_[Connector::max_burst];
-  struct sockaddr_storage remote_endpoints_[Connector::max_burst];
-  std::uint8_t current_position_;
-#else
-  std::pair<uint8_t *, std::size_t> read_msg_;
-#endif
-};
-
-}  // namespace core
-
-}  // namespace transport