hsa: move external echo apps to hsa

Type: refactor

Change-Id: I9a5c2abfd0c5444b31d9020cea918f9cd28f1ac2
Signed-off-by: Florin Coras <fcoras@cisco.com>

4 files changed, 4533 insertions, 0 deletions

diff --git a/src/plugins/hs_apps/CMakeLists.txt b/src/plugins/hs_apps/CMakeLists.txt
index d27c8512306..e7885c3d1bf 100644
--- a/src/plugins/hs_apps/CMakeLists.txt
+++ b/src/plugins/hs_apps/CMakeLists.txt
@@ -19,3 +19,25 @@ add_vpp_plugin(hs_apps
   http_server.c
   proxy.c
 )
+
+option(VPP_BUILD_SESSION_ECHO_APPS "Build session echo apps." ON)
+if(VPP_BUILD_SESSION_ECHO_APPS)
+  add_vpp_executable(tcp_echo
+    SOURCES tcp_echo.c
+    LINK_LIBRARIES vlibmemoryclient svm vppinfra pthread m rt
+    DEPENDS api_headers
+    NO_INSTALL
+  )
+  add_vpp_executable(quic_echo
+    SOURCES quic_echo.c
+    LINK_LIBRARIES vlibmemoryclient svm vppinfra pthread m rt
+    DEPENDS api_headers
+    NO_INSTALL
+  )
+  add_vpp_executable(udp_echo
+    SOURCES udp_echo.c
+    LINK_LIBRARIES vlibmemoryclient svm vppinfra pthread m rt
+    DEPENDS api_headers
+    NO_INSTALL
+  )
+endif(VPP_BUILD_SESSION_ECHO_APPS)
diff --git a/src/plugins/hs_apps/quic_echo.c b/src/plugins/hs_apps/quic_echo.c
new file mode 100644
index 00000000000..a62af642b2f
--- /dev/null
+++ b/src/plugins/hs_apps/quic_echo.c
@@ -0,0 +1,1841 @@
+/*
+ * Copyright (c) 2019 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:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <signal.h>
+
+#include <vnet/session/application_interface.h>
+#include <vlibmemory/api.h>
+
+#include <vpp/api/vpe_msg_enum.h>
+#include <svm/fifo_segment.h>
+
+#define vl_typedefs		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_typedefs
+
+/* declare message handlers for each api */
+
+#define vl_endianfun		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...)
+#define vl_printfun
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_printfun
+
+#define QUIC_ECHO_DBG 0
+#define DBG(_fmt, _args...)			\
+    if (QUIC_ECHO_DBG) 				\
+      clib_warning (_fmt, ##_args)
+
+typedef struct
+{
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+#define _(type, name) type name;
+  foreach_app_session_field
+#undef _
+  u64 vpp_session_handle;
+  u64 bytes_sent;
+  u64 bytes_to_send;
+  volatile u64 bytes_received;
+  volatile u64 bytes_to_receive;
+  f64 start;
+} echo_session_t;
+
+typedef enum
+{
+  STATE_START,
+  STATE_ATTACHED,
+  STATE_LISTEN,
+  STATE_READY,
+  STATE_DISCONNECTING,
+  STATE_FAILED,
+  STATE_DETACHED
+} connection_state_t;
+
+typedef enum
+{
+  ECHO_EVT_START,		/* app starts */
+  ECHO_EVT_FIRST_QCONNECT,	/* First connect Quic session sent */
+  ECHO_EVT_LAST_QCONNECTED,	/* All Quic session are connected */
+  ECHO_EVT_FIRST_SCONNECT,	/* First connect Stream session sent */
+  ECHO_EVT_LAST_SCONNECTED,	/* All Stream session are connected */
+  ECHO_EVT_LAST_BYTE,		/* Last byte received */
+  ECHO_EVT_EXIT,		/* app exits */
+} echo_test_evt_t;
+
+enum quic_session_type_t
+{
+  QUIC_SESSION_TYPE_QUIC = 0,
+  QUIC_SESSION_TYPE_STREAM = 1,
+  QUIC_SESSION_TYPE_LISTEN = INT32_MAX,
+};
+
+typedef struct _quic_echo_cb_vft
+{
+  void (*quic_connected_cb) (session_connected_msg_t * mp, u32 session_index);
+  void (*client_stream_connected_cb) (session_connected_msg_t * mp,
+				      u32 session_index);
+  void (*server_stream_connected_cb) (session_connected_msg_t * mp,
+				      u32 session_index);
+  void (*quic_accepted_cb) (session_accepted_msg_t * mp, u32 session_index);
+  void (*client_stream_accepted_cb) (session_accepted_msg_t * mp,
+				     u32 session_index);
+  void (*server_stream_accepted_cb) (session_accepted_msg_t * mp,
+				     u32 session_index);
+} quic_echo_cb_vft_t;
+
+
+typedef enum
+{
+  RETURN_PACKETS_NOTEST,
+  RETURN_PACKETS_LOG_WRONG,
+  RETURN_PACKETS_ASSERT,
+} test_return_packets_t;
+
+typedef struct
+{
+  /* vpe input queue */
+  svm_queue_t *vl_input_queue;
+
+  /* API client handle */
+  u32 my_client_index;
+
+  /* The URI we're playing with */
+  u8 *uri;
+
+  /* Session pool */
+  echo_session_t *sessions;
+
+  /* Hash table for disconnect processing */
+  uword *session_index_by_vpp_handles;
+  /* Handle of vpp listener session */
+  u64 listener_handle;
+
+  /* Hash table for shared segment_names */
+  uword *shared_segment_handles;
+  clib_spinlock_t segment_handles_lock;
+
+  /* intermediate rx buffer */
+  u8 *rx_buf;
+
+  int i_am_master;
+
+  /* drop all packets */
+  int no_return;
+
+  /* Our event queue */
+  svm_msg_q_t *our_event_queue;
+
+  u8 *socket_name;
+
+  pid_t my_pid;
+
+  /* For deadman timers */
+  clib_time_t clib_time;
+
+  /* State of the connection, shared between msg RX thread and main thread */
+  volatile connection_state_t state;
+
+  /* Signal variables */
+  volatile int time_to_stop;
+
+  /* VNET_API_ERROR_FOO -> "Foo" hash table */
+  uword *error_string_by_error_number;
+
+  u8 *connect_test_data;
+  pthread_t *client_thread_handles;
+  u32 *thread_args;
+  u8 test_return_packets;
+  u64 bytes_to_send;
+  u64 bytes_to_receive;
+  u32 fifo_size;
+
+  u8 *appns_id;
+  u64 appns_flags;
+  u64 appns_secret;
+
+  u32 n_clients;		/* Target number of QUIC sessions */
+  u32 n_stream_clients;		/* Target Number of STREAM sessions per QUIC session */
+  volatile u32 n_quic_clients_connected;	/* Number of connected QUIC sessions */
+  volatile u32 n_clients_connected;	/* Number of STREAM sessions connected */
+
+  u64 tx_total;
+  u64 rx_total;
+
+  /* Event based timing : start & end depend on CLI specified events */
+  u8 first_sconnect_sent;	/* Sent the first Stream session connect ? */
+  f64 start_time;
+  f64 end_time;
+  u8 timing_start_event;
+  u8 timing_end_event;
+
+  /* cb vft for QUIC scenarios */
+  quic_echo_cb_vft_t cb_vft;
+
+  /** Flag that decides if socket, instead of svm, api is used to connect to
+   * vpp. If sock api is used, shm binary api is subsequently bootstrapped
+   * and all other messages are exchanged using shm IPC. */
+  u8 use_sock_api;
+
+  /* Limit the number of incorrect data messages */
+  int max_test_msg;
+
+  fifo_segment_main_t segment_main;
+} echo_main_t;
+
+echo_main_t echo_main;
+
+#if CLIB_DEBUG > 0
+#define NITER 10000
+#else
+#define NITER 4000000
+#endif
+
+#if CLIB_DEBUG > 0
+#define TIMEOUT 10.0
+#else
+#define TIMEOUT 10.0
+#endif
+
+u8 *
+format_quic_echo_state (u8 * s, va_list * args)
+{
+  u32 state = va_arg (*args, u32);
+  if (state == STATE_START)
+    return format (s, "STATE_START");
+  if (state == STATE_ATTACHED)
+    return format (s, "STATE_ATTACHED");
+  if (state == STATE_LISTEN)
+    return format (s, "STATE_LISTEN");
+  if (state == STATE_READY)
+    return format (s, "STATE_READY");
+  if (state == STATE_DISCONNECTING)
+    return format (s, "STATE_DISCONNECTING");
+  if (state == STATE_FAILED)
+    return format (s, "STATE_FAILED");
+  if (state == STATE_DETACHED)
+    return format (s, "STATE_DETACHED");
+  else
+    return format (s, "unknown state");
+}
+
+static u8 *
+format_api_error (u8 * s, va_list * args)
+{
+  echo_main_t *em = &echo_main;
+  i32 error = va_arg (*args, u32);
+  uword *p;
+
+  p = hash_get (em->error_string_by_error_number, -error);
+
+  if (p)
+    s = format (s, "%s", p[0]);
+  else
+    s = format (s, "%d", error);
+  return s;
+}
+
+static void
+quic_echo_notify_event (echo_main_t * em, echo_test_evt_t e)
+{
+  if (em->timing_start_event == e)
+    em->start_time = clib_time_now (&em->clib_time);
+  else if (em->timing_end_event == e)
+    em->end_time = clib_time_now (&em->clib_time);
+}
+
+static uword
+echo_unformat_timing_event (unformat_input_t * input, va_list * args)
+{
+  echo_test_evt_t *a = va_arg (*args, echo_test_evt_t *);
+  if (unformat (input, "start"))
+    *a = ECHO_EVT_START;
+  else if (unformat (input, "qconnect"))
+    *a = ECHO_EVT_FIRST_QCONNECT;
+  else if (unformat (input, "qconnected"))
+    *a = ECHO_EVT_LAST_QCONNECTED;
+  else if (unformat (input, "sconnect"))
+    *a = ECHO_EVT_FIRST_SCONNECT;
+  else if (unformat (input, "sconnected"))
+    *a = ECHO_EVT_LAST_SCONNECTED;
+  else if (unformat (input, "lastbyte"))
+    *a = ECHO_EVT_LAST_BYTE;
+  else if (unformat (input, "exit"))
+    *a = ECHO_EVT_EXIT;
+  else
+    return 0;
+  return 1;
+}
+
+u8 *
+echo_format_timing_event (u8 * s, va_list * args)
+{
+  u32 timing_event = va_arg (*args, u32);
+  if (timing_event == ECHO_EVT_START)
+    return format (s, "start");
+  if (timing_event == ECHO_EVT_FIRST_QCONNECT)
+    return format (s, "qconnect");
+  if (timing_event == ECHO_EVT_LAST_QCONNECTED)
+    return format (s, "qconnected");
+  if (timing_event == ECHO_EVT_FIRST_SCONNECT)
+    return format (s, "sconnect");
+  if (timing_event == ECHO_EVT_LAST_SCONNECTED)
+    return format (s, "sconnected");
+  if (timing_event == ECHO_EVT_LAST_BYTE)
+    return format (s, "lastbyte");
+  if (timing_event == ECHO_EVT_EXIT)
+    return format (s, "exit");
+  else
+    return format (s, "unknown timing event");
+}
+
+static void
+init_error_string_table (echo_main_t * em)
+{
+  em->error_string_by_error_number = hash_create (0, sizeof (uword));
+
+#define _(n,v,s) hash_set (em->error_string_by_error_number, -v, s);
+  foreach_vnet_api_error;
+#undef _
+
+  hash_set (em->error_string_by_error_number, 99, "Misc");
+}
+
+static void handle_mq_event (echo_main_t * em, session_event_t * e,
+			     int handle_rx);
+static void echo_handle_rx (echo_main_t * em, session_event_t * e);
+
+static int
+wait_for_segment_allocation (u64 segment_handle)
+{
+  echo_main_t *em = &echo_main;
+  f64 timeout;
+  timeout = clib_time_now (&em->clib_time) + TIMEOUT;
+  uword *segment_present;
+  DBG ("Waiting for segment %lx...", segment_handle);
+  while (clib_time_now (&em->clib_time) < timeout)
+    {
+      clib_spinlock_lock (&em->segment_handles_lock);
+      segment_present = hash_get (em->shared_segment_handles, segment_handle);
+      clib_spinlock_unlock (&em->segment_handles_lock);
+      if (segment_present != 0)
+	return 0;
+      if (em->time_to_stop == 1)
+	return 0;
+    }
+  DBG ("timeout waiting for segment_allocation %lx", segment_handle);
+  return -1;
+}
+
+static int
+wait_for_disconnected_sessions (echo_main_t * em)
+{
+  f64 timeout;
+  timeout = clib_time_now (&em->clib_time) + TIMEOUT;
+  while (clib_time_now (&em->clib_time) < timeout)
+    {
+      if (hash_elts (em->session_index_by_vpp_handles) == 0)
+	return 0;
+    }
+  DBG ("timeout waiting for disconnected_sessions");
+  return -1;
+}
+
+static int
+wait_for_state_change (echo_main_t * em, connection_state_t state,
+		       f64 timeout)
+{
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+  f64 end_time = clib_time_now (&em->clib_time) + timeout;
+
+  while (!timeout || clib_time_now (&em->clib_time) < end_time)
+    {
+      if (em->state == state)
+	return 0;
+      if (em->state == STATE_FAILED)
+	return -1;
+      if (em->time_to_stop == 1)
+	return 0;
+      if (!em->our_event_queue || em->state < STATE_ATTACHED)
+	continue;
+
+      if (svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_NOWAIT, 0))
+	continue;
+      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+      handle_mq_event (em, e, 0 /* handle_rx */ );
+      svm_msg_q_free_msg (em->our_event_queue, &msg);
+    }
+  clib_warning ("timeout waiting for state %U", format_quic_echo_state,
+		state);
+  return -1;
+}
+
+static void
+notify_rx_data_to_vpp (echo_session_t * s)
+{
+  svm_fifo_t *f = s->tx_fifo;
+  return;			/* FOR NOW */
+  if (svm_fifo_set_event (f))
+    {
+      DBG ("did send event");
+      app_send_io_evt_to_vpp (s->vpp_evt_q, f->master_session_index,
+			      SESSION_IO_EVT_TX, 0 /* noblock */ );
+    }
+}
+
+void
+application_send_attach (echo_main_t * em)
+{
+  vl_api_application_attach_t *bmp;
+  vl_api_application_tls_cert_add_t *cert_mp;
+  vl_api_application_tls_key_add_t *key_mp;
+
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_APPLICATION_ATTACH);
+  bmp->client_index = em->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  bmp->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_ACCEPT_REDIRECT;
+  bmp->options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_ADD_SEGMENT;
+  bmp->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] = 16;
+  bmp->options[APP_OPTIONS_RX_FIFO_SIZE] = em->fifo_size;
+  bmp->options[APP_OPTIONS_TX_FIFO_SIZE] = em->fifo_size;
+  bmp->options[APP_OPTIONS_ADD_SEGMENT_SIZE] = 128 << 20;
+  bmp->options[APP_OPTIONS_SEGMENT_SIZE] = 256 << 20;
+  bmp->options[APP_OPTIONS_EVT_QUEUE_SIZE] = 256;
+  if (em->appns_id)
+    {
+      bmp->namespace_id_len = vec_len (em->appns_id);
+      clib_memcpy_fast (bmp->namespace_id, em->appns_id,
+			bmp->namespace_id_len);
+      bmp->options[APP_OPTIONS_FLAGS] |= em->appns_flags;
+      bmp->options[APP_OPTIONS_NAMESPACE_SECRET] = em->appns_secret;
+    }
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & bmp);
+
+  cert_mp = vl_msg_api_alloc (sizeof (*cert_mp) + test_srv_crt_rsa_len);
+  clib_memset (cert_mp, 0, sizeof (*cert_mp));
+  cert_mp->_vl_msg_id = ntohs (VL_API_APPLICATION_TLS_CERT_ADD);
+  cert_mp->client_index = em->my_client_index;
+  cert_mp->context = ntohl (0xfeedface);
+  cert_mp->cert_len = clib_host_to_net_u16 (test_srv_crt_rsa_len);
+  clib_memcpy_fast (cert_mp->cert, test_srv_crt_rsa, test_srv_crt_rsa_len);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & cert_mp);
+
+  key_mp = vl_msg_api_alloc (sizeof (*key_mp) + test_srv_key_rsa_len);
+  clib_memset (key_mp, 0, sizeof (*key_mp) + test_srv_key_rsa_len);
+  key_mp->_vl_msg_id = ntohs (VL_API_APPLICATION_TLS_KEY_ADD);
+  key_mp->client_index = em->my_client_index;
+  key_mp->context = ntohl (0xfeedface);
+  key_mp->key_len = clib_host_to_net_u16 (test_srv_key_rsa_len);
+  clib_memcpy_fast (key_mp->key, test_srv_key_rsa, test_srv_key_rsa_len);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & key_mp);
+}
+
+static int
+application_attach (echo_main_t * em)
+{
+  application_send_attach (em);
+  return wait_for_state_change (em, STATE_ATTACHED, TIMEOUT);
+}
+
+void
+application_detach (echo_main_t * em)
+{
+  vl_api_application_detach_t *bmp;
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_APPLICATION_DETACH);
+  bmp->client_index = em->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & bmp);
+
+  DBG ("%s", "Sent detach");
+}
+
+static int
+ssvm_segment_attach (char *name, ssvm_segment_type_t type, int fd)
+{
+  fifo_segment_create_args_t _a, *a = &_a;
+  fifo_segment_main_t *sm = &echo_main.segment_main;
+  int rv;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->segment_name = (char *) name;
+  a->segment_type = type;
+
+  if (type == SSVM_SEGMENT_MEMFD)
+    a->memfd_fd = fd;
+
+  if ((rv = fifo_segment_attach (sm, a)))
+    {
+      clib_warning ("svm_fifo_segment_attach ('%s') failed", name);
+      return rv;
+    }
+  vec_reset_length (a->new_segment_indices);
+  return 0;
+}
+
+static void
+vl_api_application_attach_reply_t_handler (vl_api_application_attach_reply_t *
+					   mp)
+{
+  echo_main_t *em = &echo_main;
+  int *fds = 0;
+  u32 n_fds = 0;
+  u64 segment_handle;
+  segment_handle = clib_net_to_host_u64 (mp->segment_handle);
+  DBG ("Attached returned app %u", htons (mp->app_index));
+
+  if (mp->retval)
+    {
+      clib_warning ("attach failed: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      goto failed;
+    }
+
+  if (mp->segment_name_length == 0)
+    {
+      clib_warning ("segment_name_length zero");
+      goto failed;
+    }
+
+  ASSERT (mp->app_event_queue_address);
+  em->our_event_queue = uword_to_pointer (mp->app_event_queue_address,
+					  svm_msg_q_t *);
+
+  if (mp->n_fds)
+    {
+      vec_validate (fds, mp->n_fds);
+      vl_socket_client_recv_fd_msg (fds, mp->n_fds, 5);
+
+      if (mp->fd_flags & SESSION_FD_F_VPP_MQ_SEGMENT)
+	if (ssvm_segment_attach (0, SSVM_SEGMENT_MEMFD, fds[n_fds++]))
+	  goto failed;
+
+      if (mp->fd_flags & SESSION_FD_F_MEMFD_SEGMENT)
+	if (ssvm_segment_attach ((char *) mp->segment_name,
+				 SSVM_SEGMENT_MEMFD, fds[n_fds++]))
+	  goto failed;
+
+      if (mp->fd_flags & SESSION_FD_F_MQ_EVENTFD)
+	svm_msg_q_set_consumer_eventfd (em->our_event_queue, fds[n_fds++]);
+
+      vec_free (fds);
+    }
+  else
+    {
+      if (ssvm_segment_attach ((char *) mp->segment_name, SSVM_SEGMENT_SHM,
+			       -1))
+	goto failed;
+    }
+  clib_spinlock_lock (&em->segment_handles_lock);
+  hash_set (em->shared_segment_handles, segment_handle, 1);
+  clib_spinlock_unlock (&em->segment_handles_lock);
+  DBG ("Mapped new segment %lx", segment_handle);
+
+  em->state = STATE_ATTACHED;
+  return;
+failed:
+  em->state = STATE_FAILED;
+  return;
+}
+
+static void
+vl_api_application_detach_reply_t_handler (vl_api_application_detach_reply_t *
+					   mp)
+{
+  if (mp->retval)
+    clib_warning ("detach returned with err: %d", mp->retval);
+  echo_main.state = STATE_DETACHED;
+}
+
+static void
+stop_signal (int signum)
+{
+  echo_main_t *um = &echo_main;
+  um->time_to_stop = 1;
+}
+
+static clib_error_t *
+setup_signal_handlers (void)
+{
+  signal (SIGINT, stop_signal);
+  signal (SIGQUIT, stop_signal);
+  signal (SIGTERM, stop_signal);
+  return 0;
+}
+
+int
+connect_to_vpp (char *name)
+{
+  echo_main_t *em = &echo_main;
+  api_main_t *am = &api_main;
+
+  if (em->use_sock_api)
+    {
+      if (vl_socket_client_connect ((char *) em->socket_name, name,
+				    0 /* default rx, tx buffer */ ))
+	{
+	  clib_warning ("socket connect failed");
+	  return -1;
+	}
+
+      if (vl_socket_client_init_shm (0, 1 /* want_pthread */ ))
+	{
+	  clib_warning ("init shm api failed");
+	  return -1;
+	}
+    }
+  else
+    {
+      if (vl_client_connect_to_vlib ("/vpe-api", name, 32) < 0)
+	{
+	  clib_warning ("shmem connect failed");
+	  return -1;
+	}
+    }
+  em->vl_input_queue = am->shmem_hdr->vl_input_queue;
+  em->my_client_index = am->my_client_index;
+  return 0;
+}
+
+void
+disconnect_from_vpp (echo_main_t * em)
+{
+  if (em->use_sock_api)
+    vl_socket_client_disconnect ();
+  else
+    vl_client_disconnect_from_vlib ();
+}
+
+static void
+vl_api_map_another_segment_t_handler (vl_api_map_another_segment_t * mp)
+{
+  fifo_segment_main_t *sm = &echo_main.segment_main;
+  fifo_segment_create_args_t _a, *a = &_a;
+  echo_main_t *em = &echo_main;
+  int rv;
+  int *fds = 0;
+  u64 segment_handle;
+  segment_handle = clib_net_to_host_u64 (mp->segment_handle);
+
+  if (mp->fd_flags & SESSION_FD_F_MEMFD_SEGMENT)
+    {
+      vec_validate (fds, 1);
+      vl_socket_client_recv_fd_msg (fds, 1, 5);
+      if (ssvm_segment_attach
+	  ((char *) mp->segment_name, SSVM_SEGMENT_MEMFD, fds[0]))
+	clib_warning
+	  ("svm_fifo_segment_attach ('%s') failed on SSVM_SEGMENT_MEMFD",
+	   mp->segment_name);
+      clib_spinlock_lock (&em->segment_handles_lock);
+      hash_set (em->shared_segment_handles, segment_handle, 1);
+      clib_spinlock_unlock (&em->segment_handles_lock);
+      vec_free (fds);
+      DBG ("Mapped new segment %lx", segment_handle);
+      return;
+    }
+
+  clib_memset (a, 0, sizeof (*a));
+  a->segment_name = (char *) mp->segment_name;
+  a->segment_size = mp->segment_size;
+  /* Attach to the segment vpp created */
+  rv = fifo_segment_attach (sm, a);
+  if (rv)
+    {
+      clib_warning ("svm_fifo_segment_attach ('%s') failed",
+		    mp->segment_name);
+      return;
+    }
+  clib_spinlock_lock (&em->segment_handles_lock);
+  hash_set (em->shared_segment_handles, mp->segment_name, 1);
+  clib_spinlock_unlock (&em->segment_handles_lock);
+  clib_warning ("Mapped new segment '%s' size %d", mp->segment_name,
+		mp->segment_size);
+}
+
+static void
+session_print_stats (echo_main_t * em, echo_session_t * session)
+{
+  f64 deltat = clib_time_now (&em->clib_time) - session->start;
+  fformat (stdout, "Session %x done in %.6fs RX[%.4f] TX[%.4f] Gbit/s\n",
+	   session->session_index, deltat,
+	   (session->bytes_received * 8.0) / deltat / 1e9,
+	   (session->bytes_sent * 8.0) / deltat / 1e9);
+}
+
+static void
+print_global_stats (echo_main_t * em)
+{
+  f64 deltat = em->end_time - em->start_time;
+  u8 *s = format (0, "%U:%U",
+		  echo_format_timing_event, em->timing_start_event,
+		  echo_format_timing_event, em->timing_end_event);
+  fformat (stdout, "Timinig %s\n", s);
+  fformat (stdout, "-------- TX --------\n");
+  fformat (stdout, "%lld bytes (%lld mbytes, %lld gbytes) in %.2f seconds\n",
+	   em->tx_total, em->tx_total / (1ULL << 20),
+	   em->tx_total / (1ULL << 30), deltat);
+  fformat (stdout, "%.4f Gbit/second\n", (em->tx_total * 8.0) / deltat / 1e9);
+  fformat (stdout, "-------- RX --------\n");
+  fformat (stdout, "%lld bytes (%lld mbytes, %lld gbytes) in %.2f seconds\n",
+	   em->rx_total, em->rx_total / (1ULL << 20),
+	   em->rx_total / (1ULL << 30), deltat);
+  fformat (stdout, "%.4f Gbit/second\n", (em->rx_total * 8.0) / deltat / 1e9);
+  fformat (stdout, "--------------------\n");
+}
+
+
+static void
+test_recv_bytes (echo_main_t * em, echo_session_t * s, u8 * rx_buf,
+		 u32 n_read)
+{
+  int i;
+  u8 expected;
+  for (i = 0; i < n_read; i++)
+    {
+      expected = (s->bytes_received + i) & 0xff;
+      if (rx_buf[i] != expected && em->max_test_msg > 0)
+	{
+	  clib_warning
+	    ("Session[%lx][0x%lx] byte[%lld], got 0x%x but expected 0x%x",
+	     s->session_index, s->vpp_session_handle, s->bytes_received + i,
+	     rx_buf[i], expected);
+	  em->max_test_msg--;
+	  if (em->max_test_msg == 0)
+	    clib_warning ("Too many errors, hiding next ones");
+	  if (em->test_return_packets == RETURN_PACKETS_ASSERT)
+	    ASSERT (0);
+	}
+    }
+}
+
+static void
+recv_data_chunk (echo_main_t * em, echo_session_t * s, u8 * rx_buf)
+{
+  int n_to_read, n_read;
+
+  n_to_read = svm_fifo_max_dequeue (s->rx_fifo);
+  if (!n_to_read)
+    return;
+
+  do
+    {
+      n_read =
+	app_recv_stream ((app_session_t *) s, rx_buf, vec_len (rx_buf));
+      if (n_read <= 0)
+	break;
+      notify_rx_data_to_vpp (s);
+      if (em->test_return_packets)
+	test_recv_bytes (em, s, rx_buf, n_read);
+
+      ASSERT (s->bytes_to_receive >= n_read);
+      n_to_read -= n_read;
+      s->bytes_received += n_read;
+      s->bytes_to_receive -= n_read;
+    }
+  while (n_to_read > 0);
+}
+
+static void
+send_data_chunk (echo_main_t * em, echo_session_t * s)
+{
+  u64 test_buf_len, bytes_this_chunk, test_buf_offset;
+  u8 *test_data = em->connect_test_data;
+  int n_sent;
+
+  test_buf_len = vec_len (test_data);
+  test_buf_offset = s->bytes_sent % test_buf_len;
+  bytes_this_chunk = clib_min (test_buf_len - test_buf_offset,
+			       s->bytes_to_send);
+
+  n_sent = app_send_stream ((app_session_t *) s, test_data + test_buf_offset,
+			    bytes_this_chunk, 0);
+
+  if (n_sent > 0)
+    {
+      s->bytes_to_send -= n_sent;
+      s->bytes_sent += n_sent;
+    }
+}
+
+/*
+ * Rx/Tx polling thread per connection
+ */
+static void *
+client_thread_fn (void *arg)
+{
+  echo_main_t *em = &echo_main;
+  u8 *rx_buf = 0;
+  u32 session_index = *(u32 *) arg;
+  echo_session_t *s;
+
+  vec_validate (rx_buf, 1 << 20);
+
+  while (!em->time_to_stop && em->state != STATE_READY)
+    ;
+
+  s = pool_elt_at_index (em->sessions, session_index);
+  while (!em->time_to_stop)
+    {
+      send_data_chunk (em, s);
+      recv_data_chunk (em, s, rx_buf);
+      if (!s->bytes_to_send && !s->bytes_to_receive)
+	break;
+    }
+
+  DBG ("[%lu/%lu] -> S(%x) -> [%lu/%lu]",
+       s->bytes_received, s->bytes_received + s->bytes_to_receive,
+       session_index, s->bytes_sent, s->bytes_sent + s->bytes_to_send);
+  em->tx_total += s->bytes_sent;
+  em->rx_total += s->bytes_received;
+  em->n_clients_connected--;
+
+  if (em->n_clients_connected == 0)
+    quic_echo_notify_event (em, ECHO_EVT_LAST_BYTE);
+
+  pthread_exit (0);
+}
+
+static void
+echo_send_connect (echo_main_t * em, u8 * uri, u32 opaque)
+{
+  vl_api_connect_uri_t *cmp;
+  cmp = vl_msg_api_alloc (sizeof (*cmp));
+  clib_memset (cmp, 0, sizeof (*cmp));
+
+  cmp->_vl_msg_id = ntohs (VL_API_CONNECT_URI);
+  cmp->client_index = em->my_client_index;
+  cmp->context = ntohl (opaque);
+  memcpy (cmp->uri, uri, vec_len (uri));
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & cmp);
+}
+
+static void
+client_disconnect_session (echo_main_t * em, echo_session_t * s)
+{
+  vl_api_disconnect_session_t *dmp;
+  dmp = vl_msg_api_alloc (sizeof (*dmp));
+  clib_memset (dmp, 0, sizeof (*dmp));
+  dmp->_vl_msg_id = ntohs (VL_API_DISCONNECT_SESSION);
+  dmp->client_index = em->my_client_index;
+  dmp->handle = s->vpp_session_handle;
+  DBG ("Sending Session disonnect handle %lu", dmp->handle);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & dmp);
+  pool_put (em->sessions, s);
+  clib_memset (s, 0xfe, sizeof (*s));
+}
+
+static void
+session_bound_handler (session_bound_msg_t * mp)
+{
+  echo_main_t *em = &echo_main;
+
+  if (mp->retval)
+    {
+      clib_warning ("bind failed: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      em->state = STATE_FAILED;
+      return;
+    }
+
+  clib_warning ("listening on %U:%u", format_ip46_address, mp->lcl_ip,
+		mp->lcl_is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
+		clib_net_to_host_u16 (mp->lcl_port));
+  em->listener_handle = mp->handle;
+  em->state = STATE_LISTEN;
+}
+
+static void
+session_accepted_handler (session_accepted_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  session_accepted_reply_msg_t *rmp;
+  svm_fifo_t *rx_fifo, *tx_fifo;
+  echo_main_t *em = &echo_main;
+  echo_session_t *session;
+  u32 session_index;
+
+  /* Allocate local session and set it up */
+  pool_get (em->sessions, session);
+  session_index = session - em->sessions;
+
+  if (wait_for_segment_allocation (mp->segment_handle))
+    return;
+
+  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  rx_fifo->client_session_index = session_index;
+  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+  tx_fifo->client_session_index = session_index;
+
+  session->rx_fifo = rx_fifo;
+  session->tx_fifo = tx_fifo;
+  session->session_index = session_index;
+  session->vpp_session_handle = mp->handle;
+  session->start = clib_time_now (&em->clib_time);
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					 svm_msg_q_t *);
+
+  /* Add it to lookup table */
+  DBG ("Accepted session handle %lx, Listener %lx idx %lu", mp->handle,
+       mp->listener_handle, session_index);
+  hash_set (em->session_index_by_vpp_handles, mp->handle, session_index);
+
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_ACCEPTED_REPLY);
+  rmp = (session_accepted_reply_msg_t *) app_evt->evt->data;
+  rmp->handle = mp->handle;
+  rmp->context = mp->context;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+
+  DBG ("SSession handle is %lu", mp->handle);
+  if (mp->listener_handle == em->listener_handle)
+    {
+      if (em->cb_vft.quic_accepted_cb)
+	em->cb_vft.quic_accepted_cb (mp, session_index);
+      em->n_quic_clients_connected++;
+    }
+  else if (em->i_am_master)
+    {
+      if (em->cb_vft.server_stream_accepted_cb)
+	em->cb_vft.server_stream_accepted_cb (mp, session_index);
+      em->n_clients_connected++;
+    }
+  else
+    {
+      if (em->cb_vft.client_stream_accepted_cb)
+	em->cb_vft.client_stream_accepted_cb (mp, session_index);
+      em->n_clients_connected++;
+    }
+
+  if (em->n_clients_connected == em->n_clients * em->n_stream_clients)
+    {
+      em->state = STATE_READY;
+      quic_echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
+    }
+  if (em->n_quic_clients_connected == em->n_clients)
+    quic_echo_notify_event (em, ECHO_EVT_LAST_QCONNECTED);
+}
+
+static void
+session_connected_handler (session_connected_msg_t * mp)
+{
+  echo_main_t *em = &echo_main;
+  echo_session_t *session;
+  u32 session_index;
+  svm_fifo_t *rx_fifo, *tx_fifo;
+
+  if (mp->retval)
+    {
+      clib_warning ("connection failed with code: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      em->state = STATE_FAILED;
+      return;
+    }
+
+  pool_get (em->sessions, session);
+  clib_memset (session, 0, sizeof (*session));
+  session_index = session - em->sessions;
+  DBG ("CONNECTED session[%lx][0x%lx]", session_index, mp->handle);
+
+  if (wait_for_segment_allocation (mp->segment_handle))
+    return;
+
+  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  rx_fifo->client_session_index = session_index;
+  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+  tx_fifo->client_session_index = session_index;
+
+  session->rx_fifo = rx_fifo;
+  session->tx_fifo = tx_fifo;
+  session->vpp_session_handle = mp->handle;
+  session->session_index = session_index;
+  session->start = clib_time_now (&em->clib_time);
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					 svm_msg_q_t *);
+
+  DBG ("Connected session handle %lx, idx %lu RX[%lx] TX[%lx]", mp->handle,
+       session_index, rx_fifo, tx_fifo);
+  hash_set (em->session_index_by_vpp_handles, mp->handle, session_index);
+
+  if (mp->context == QUIC_SESSION_TYPE_QUIC)
+    {
+      if (em->cb_vft.quic_connected_cb)
+	em->cb_vft.quic_connected_cb (mp, session_index);
+      em->n_quic_clients_connected++;
+    }
+  else if (em->i_am_master)
+    {
+      if (em->cb_vft.server_stream_connected_cb)
+	em->cb_vft.server_stream_connected_cb (mp, session_index);
+      em->n_clients_connected++;
+    }
+  else
+    {
+      if (em->cb_vft.client_stream_connected_cb)
+	em->cb_vft.client_stream_connected_cb (mp, session_index);
+      em->n_clients_connected++;
+    }
+
+  if (em->n_clients_connected == em->n_clients * em->n_stream_clients)
+    {
+      em->state = STATE_READY;
+      quic_echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
+    }
+  if (em->n_quic_clients_connected == em->n_clients)
+    quic_echo_notify_event (em, ECHO_EVT_LAST_QCONNECTED);
+}
+
+/*
+ *
+ *  ECHO Callback definitions
+ *
+ */
+
+
+static void
+echo_on_connected_connect (session_connected_msg_t * mp, u32 session_index)
+{
+  echo_main_t *em = &echo_main;
+  u8 *uri = format (0, "QUIC://session/%lu", mp->handle);
+  int i;
+
+  if (!em->first_sconnect_sent)
+    {
+      em->first_sconnect_sent = 1;
+      quic_echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
+    }
+  for (i = 0; i < em->n_stream_clients; i++)
+    {
+      DBG ("CONNECT : new QUIC stream #%d: %s", i, uri);
+      echo_send_connect (em, uri, QUIC_SESSION_TYPE_STREAM);
+    }
+
+  clib_warning ("session %u (0x%llx) connected with local ip %U port %d",
+		session_index, mp->handle, format_ip46_address, &mp->lcl.ip,
+		mp->lcl.is_ip4, clib_net_to_host_u16 (mp->lcl.port));
+}
+
+static void
+echo_on_connected_send (session_connected_msg_t * mp, u32 session_index)
+{
+  echo_main_t *em = &echo_main;
+  int rv;
+  echo_session_t *session;
+
+  DBG ("Stream Session Connected");
+
+  session = pool_elt_at_index (em->sessions, session_index);
+  session->bytes_to_send = em->bytes_to_send;
+  session->bytes_to_receive = em->bytes_to_receive;
+
+  /*
+   * Start RX thread
+   */
+  em->thread_args[em->n_clients_connected] = session_index;
+  rv = pthread_create (&em->client_thread_handles[em->n_clients_connected],
+		       NULL /*attr */ , client_thread_fn,
+		       (void *) &em->thread_args[em->n_clients_connected]);
+  if (rv)
+    {
+      clib_warning ("pthread_create returned %d", rv);
+      return;
+    }
+}
+
+static void
+echo_on_connected_error (session_connected_msg_t * mp, u32 session_index)
+{
+  clib_warning ("Got a wrong connected on session %u [%lx]", session_index,
+		mp->handle);
+}
+
+static void
+echo_on_accept_recv (session_accepted_msg_t * mp, u32 session_index)
+{
+  echo_main_t *em = &echo_main;
+  int rv;
+  echo_session_t *session;
+
+  session = pool_elt_at_index (em->sessions, session_index);
+  session->bytes_to_send = em->bytes_to_send;
+  session->bytes_to_receive = em->bytes_to_receive;
+
+  DBG ("Stream session accepted 0x%lx, expecting %lu bytes",
+       session->vpp_session_handle, session->bytes_to_receive);
+
+  /*
+   * Start RX thread
+   */
+  em->thread_args[em->n_clients_connected] = session_index;
+  rv = pthread_create (&em->client_thread_handles[em->n_clients_connected],
+		       NULL /*attr */ , client_thread_fn,
+		       (void *) &em->thread_args[em->n_clients_connected]);
+  if (rv)
+    {
+      clib_warning ("pthread_create returned %d", rv);
+      return;
+    }
+
+}
+
+static void
+echo_on_accept_connect (session_accepted_msg_t * mp, u32 session_index)
+{
+  echo_main_t *em = &echo_main;
+  DBG ("Accept on QSession index %u", mp->handle);
+  u8 *uri = format (0, "QUIC://session/%lu", mp->handle);
+  u32 i;
+
+  if (!em->first_sconnect_sent)
+    {
+      em->first_sconnect_sent = 1;
+      quic_echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
+    }
+  for (i = 0; i < em->n_stream_clients; i++)
+    {
+      DBG ("ACCEPT : new QUIC stream #%d: %s", i, uri);
+      echo_send_connect (em, uri, QUIC_SESSION_TYPE_STREAM);
+    }
+}
+
+static void
+echo_on_accept_error (session_accepted_msg_t * mp, u32 session_index)
+{
+  clib_warning ("Got a wrong accept on session %u [%lx]", session_index,
+		mp->handle);
+}
+
+static void
+echo_on_accept_log_ip (session_accepted_msg_t * mp, u32 session_index)
+{
+  u8 *ip_str;
+  ip_str = format (0, "%U", format_ip46_address, &mp->rmt.ip, mp->rmt.is_ip4);
+  clib_warning ("Accepted session from: %s:%d", ip_str,
+		clib_net_to_host_u16 (mp->rmt.port));
+
+}
+
+static const quic_echo_cb_vft_t default_cb_vft = {
+  /* Qsessions */
+  .quic_accepted_cb = &echo_on_accept_log_ip,
+  .quic_connected_cb = &echo_on_connected_connect,
+  /* client initiated streams */
+  .server_stream_accepted_cb = NULL,
+  .client_stream_connected_cb = &echo_on_connected_send,
+  /* server initiated streams */
+  .client_stream_accepted_cb = &echo_on_accept_error,
+  .server_stream_connected_cb = &echo_on_connected_error,
+};
+
+static const quic_echo_cb_vft_t server_stream_cb_vft = {
+  /* Qsessions */
+  .quic_accepted_cb = &echo_on_accept_connect,
+  .quic_connected_cb = NULL,
+  /* client initiated streams */
+  .server_stream_accepted_cb = &echo_on_accept_error,
+  .client_stream_connected_cb = &echo_on_connected_error,
+  /* server initiated streams */
+  .client_stream_accepted_cb = &echo_on_accept_recv,
+  .server_stream_connected_cb = &echo_on_connected_send,
+};
+
+static uword
+echo_unformat_quic_setup_vft (unformat_input_t * input, va_list * args)
+{
+  echo_main_t *em = &echo_main;
+  if (unformat (input, "serverstream"))
+    {
+      clib_warning ("Using QUIC server initiated streams");
+      em->no_return = 1;
+      em->cb_vft = server_stream_cb_vft;
+      return 1;
+    }
+  else if (unformat (input, "default"))
+    return 1;
+  return 0;
+}
+
+static uword
+echo_unformat_data (unformat_input_t * input, va_list * args)
+{
+  u64 _a;
+  u64 *a = va_arg (*args, u64 *);
+  if (unformat (input, "%lluGb", &_a))
+    {
+      *a = _a << 30;
+      return 1;
+    }
+  else if (unformat (input, "%lluMb", &_a))
+    {
+      *a = _a << 20;
+      return 1;
+    }
+  else if (unformat (input, "%lluKb", &_a))
+    {
+      *a = _a << 10;
+      return 1;
+    }
+  else if (unformat (input, "%llu", a))
+    return 1;
+  return 0;
+}
+
+/*
+ *
+ *  End of ECHO callback definitions
+ *
+ */
+
+static void
+session_disconnected_handler (session_disconnected_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  session_disconnected_reply_msg_t *rmp;
+  echo_main_t *em = &echo_main;
+  echo_session_t *session = 0;
+  uword *p;
+  int rv = 0;
+  DBG ("Disonnected session handle %lx", mp->handle);
+  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
+  if (!p)
+    {
+      clib_warning ("couldn't find session key %llx", mp->handle);
+      return;
+    }
+
+  session = pool_elt_at_index (em->sessions, p[0]);
+  hash_unset (em->session_index_by_vpp_handles, mp->handle);
+
+  pool_put (em->sessions, session);
+
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_DISCONNECTED_REPLY);
+  rmp = (session_disconnected_reply_msg_t *) app_evt->evt->data;
+  rmp->retval = rv;
+  rmp->handle = mp->handle;
+  rmp->context = mp->context;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+
+  session_print_stats (em, session);
+}
+
+static void
+session_reset_handler (session_reset_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  echo_main_t *em = &echo_main;
+  session_reset_reply_msg_t *rmp;
+  echo_session_t *session = 0;
+  uword *p;
+  int rv = 0;
+
+  DBG ("Reset session handle %lx", mp->handle);
+  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
+
+  if (p)
+    {
+      session = pool_elt_at_index (em->sessions, p[0]);
+      clib_warning ("got reset");
+      /* Cleanup later */
+      em->time_to_stop = 1;
+    }
+  else
+    {
+      clib_warning ("couldn't find session key %llx", mp->handle);
+      return;
+    }
+
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_RESET_REPLY);
+  rmp = (session_reset_reply_msg_t *) app_evt->evt->data;
+  rmp->retval = rv;
+  rmp->handle = mp->handle;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+}
+
+static void
+handle_mq_event (echo_main_t * em, session_event_t * e, int handle_rx)
+{
+  switch (e->event_type)
+    {
+    case SESSION_CTRL_EVT_BOUND:
+      DBG ("SESSION_CTRL_EVT_BOUND");
+      session_bound_handler ((session_bound_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_ACCEPTED:
+      DBG ("SESSION_CTRL_EVT_ACCEPTED");
+      session_accepted_handler ((session_accepted_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_CONNECTED:
+      DBG ("SESSION_CTRL_EVT_CONNECTED");
+      session_connected_handler ((session_connected_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED:
+      DBG ("SESSION_CTRL_EVT_DISCONNECTED");
+      session_disconnected_handler ((session_disconnected_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_RESET:
+      DBG ("SESSION_CTRL_EVT_RESET");
+      session_reset_handler ((session_reset_msg_t *) e->data);
+      break;
+    case SESSION_IO_EVT_RX:
+      DBG ("SESSION_IO_EVT_RX");
+      if (handle_rx)
+	echo_handle_rx (em, e);
+      break;
+    default:
+      clib_warning ("unhandled event %u", e->event_type);
+    }
+}
+
+static int
+clients_run (echo_main_t * em)
+{
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+  echo_session_t *s;
+  hash_pair_t *p;
+  int i;
+
+  /*
+   * Attach and connect the clients
+   */
+  if (application_attach (em))
+    return -1;
+
+  quic_echo_notify_event (em, ECHO_EVT_FIRST_QCONNECT);
+  for (i = 0; i < em->n_clients; i++)
+    echo_send_connect (em, em->uri, QUIC_SESSION_TYPE_QUIC);
+
+  wait_for_state_change (em, STATE_READY, TIMEOUT);
+
+  /*
+   * Wait for client threads to send the data
+   */
+  DBG ("Waiting for data on %u clients", em->n_clients_connected);
+  while (em->n_clients_connected)
+    {
+      if (svm_msg_q_is_empty (em->our_event_queue))
+	continue;
+      if (svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_TIMEDWAIT, 1))
+	continue;
+      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+      handle_mq_event (em, e, 0 /* handle_rx */ );
+      svm_msg_q_free_msg (em->our_event_queue, &msg);
+    }
+
+  /* *INDENT-OFF* */
+  hash_foreach_pair (p, em->session_index_by_vpp_handles,
+    ({
+      s = pool_elt_at_index (em->sessions, p->value[0]);
+      DBG ("Sending disconnect on session %lu", p->key);
+      client_disconnect_session (em, s);
+    }));
+  /* *INDENT-ON* */
+
+  wait_for_disconnected_sessions (em);
+  application_detach (em);
+  return 0;
+}
+
+static void
+vl_api_bind_uri_reply_t_handler (vl_api_bind_uri_reply_t * mp)
+{
+  echo_main_t *em = &echo_main;
+  if (mp->retval)
+    {
+      clib_warning ("bind failed: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      em->state = STATE_FAILED;
+      return;
+    }
+
+  em->state = STATE_LISTEN;
+}
+
+static void
+vl_api_unbind_uri_reply_t_handler (vl_api_unbind_uri_reply_t * mp)
+{
+  echo_main_t *em = &echo_main;
+
+  if (mp->retval != 0)
+    clib_warning ("returned %d", ntohl (mp->retval));
+
+  em->state = STATE_START;
+}
+
+u8 *
+format_ip4_address (u8 * s, va_list * args)
+{
+  u8 *a = va_arg (*args, u8 *);
+  return format (s, "%d.%d.%d.%d", a[0], a[1], a[2], a[3]);
+}
+
+u8 *
+format_ip6_address (u8 * s, va_list * args)
+{
+  ip6_address_t *a = va_arg (*args, ip6_address_t *);
+  u32 i, i_max_n_zero, max_n_zeros, i_first_zero, n_zeros, last_double_colon;
+
+  i_max_n_zero = ARRAY_LEN (a->as_u16);
+  max_n_zeros = 0;
+  i_first_zero = i_max_n_zero;
+  n_zeros = 0;
+  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
+    {
+      u32 is_zero = a->as_u16[i] == 0;
+      if (is_zero && i_first_zero >= ARRAY_LEN (a->as_u16))
+	{
+	  i_first_zero = i;
+	  n_zeros = 0;
+	}
+      n_zeros += is_zero;
+      if ((!is_zero && n_zeros > max_n_zeros)
+	  || (i + 1 >= ARRAY_LEN (a->as_u16) && n_zeros > max_n_zeros))
+	{
+	  i_max_n_zero = i_first_zero;
+	  max_n_zeros = n_zeros;
+	  i_first_zero = ARRAY_LEN (a->as_u16);
+	  n_zeros = 0;
+	}
+    }
+
+  last_double_colon = 0;
+  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
+    {
+      if (i == i_max_n_zero && max_n_zeros > 1)
+	{
+	  s = format (s, "::");
+	  i += max_n_zeros - 1;
+	  last_double_colon = 1;
+	}
+      else
+	{
+	  s = format (s, "%s%x",
+		      (last_double_colon || i == 0) ? "" : ":",
+		      clib_net_to_host_u16 (a->as_u16[i]));
+	  last_double_colon = 0;
+	}
+    }
+
+  return s;
+}
+
+/* Format an IP46 address. */
+u8 *
+format_ip46_address (u8 * s, va_list * args)
+{
+  ip46_address_t *ip46 = va_arg (*args, ip46_address_t *);
+  ip46_type_t type = va_arg (*args, ip46_type_t);
+  int is_ip4 = 1;
+
+  switch (type)
+    {
+    case IP46_TYPE_ANY:
+      is_ip4 = ip46_address_is_ip4 (ip46);
+      break;
+    case IP46_TYPE_IP4:
+      is_ip4 = 1;
+      break;
+    case IP46_TYPE_IP6:
+      is_ip4 = 0;
+      break;
+    }
+
+  return is_ip4 ?
+    format (s, "%U", format_ip4_address, &ip46->ip4) :
+    format (s, "%U", format_ip6_address, &ip46->ip6);
+}
+
+static void
+echo_handle_rx (echo_main_t * em, session_event_t * e)
+{
+  int n_read, max_dequeue, n_sent;
+  u32 offset, to_dequeue;
+  echo_session_t *s;
+  s = pool_elt_at_index (em->sessions, e->session_index);
+
+  /* Clear event only once. Otherwise, if we do it in the loop by calling
+   * app_recv_stream, we may end up with a lot of unhandled rx events on the
+   * message queue */
+  svm_fifo_unset_event (s->rx_fifo);
+  max_dequeue = svm_fifo_max_dequeue (s->rx_fifo);
+  if (PREDICT_FALSE (!max_dequeue))
+    return;
+  do
+    {
+      /* The options here are to limit ourselves to max_dequeue or read
+       * even the data that was enqueued while we were dequeueing and which
+       * now has an rx event in the mq. Either of the two work. */
+      to_dequeue = clib_min (max_dequeue, vec_len (em->rx_buf));
+      n_read = app_recv_stream_raw (s->rx_fifo, em->rx_buf, to_dequeue,
+				    0 /* clear evt */ , 0 /* peek */ );
+
+      if (n_read <= 0)
+	break;
+      DBG ("Notify cause %u bytes", n_read);
+      notify_rx_data_to_vpp (s);
+      if (em->test_return_packets)
+	test_recv_bytes (em, s, em->rx_buf, n_read);
+
+      max_dequeue -= n_read;
+      s->bytes_received += n_read;
+      s->bytes_to_receive -= n_read;
+
+      /* Reflect if a non-drop session */
+      if (!em->no_return)
+	{
+	  offset = 0;
+	  do
+	    {
+	      n_sent = app_send_stream ((app_session_t *) s,
+					em->rx_buf + offset,
+					n_read, SVM_Q_WAIT);
+	      if (n_sent <= 0)
+		continue;
+	      n_read -= n_sent;
+	      s->bytes_to_send -= n_sent;
+	      s->bytes_sent += n_sent;
+	      offset += n_sent;
+	    }
+	  while (n_read > 0);
+	}
+    }
+  while (max_dequeue > 0 && !em->time_to_stop);
+}
+
+static void
+server_handle_mq (echo_main_t * em)
+{
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+
+  while (1)
+    {
+      int rc = svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_TIMEDWAIT, 1);
+      if (PREDICT_FALSE (rc == ETIMEDOUT && em->time_to_stop))
+	break;
+      if (rc == ETIMEDOUT)
+	continue;
+      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+      handle_mq_event (em, e, em->state == STATE_READY /* handle_rx */ );
+      svm_msg_q_free_msg (em->our_event_queue, &msg);
+    }
+}
+
+static void
+server_send_listen (echo_main_t * em)
+{
+  vl_api_bind_uri_t *bmp;
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_BIND_URI);
+  bmp->client_index = em->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  memcpy (bmp->uri, em->uri, vec_len (em->uri));
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & bmp);
+}
+
+static void
+server_send_unbind (echo_main_t * em)
+{
+  vl_api_unbind_uri_t *ump;
+
+  ump = vl_msg_api_alloc (sizeof (*ump));
+  clib_memset (ump, 0, sizeof (*ump));
+
+  ump->_vl_msg_id = ntohs (VL_API_UNBIND_URI);
+  ump->client_index = em->my_client_index;
+  memcpy (ump->uri, em->uri, vec_len (em->uri));
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & ump);
+}
+
+static int
+server_run (echo_main_t * em)
+{
+  echo_session_t *session;
+  int i;
+
+  /* $$$$ hack preallocation */
+  for (i = 0; i < 200000; i++)
+    {
+      pool_get (em->sessions, session);
+      clib_memset (session, 0, sizeof (*session));
+    }
+  for (i = 0; i < 200000; i++)
+    pool_put_index (em->sessions, i);
+
+  if (application_attach (em))
+    return -1;
+
+  /* Bind to uri */
+  server_send_listen (em);
+  if (wait_for_state_change (em, STATE_READY, 0))
+    return -2;
+
+  /* Enter handle event loop */
+  server_handle_mq (em);
+
+  /* Cleanup */
+  server_send_unbind (em);
+  application_detach (em);
+  fformat (stdout, "Test complete...\n");
+  return 0;
+}
+
+static void
+vl_api_disconnect_session_reply_t_handler (vl_api_disconnect_session_reply_t *
+					   mp)
+{
+  echo_main_t *em = &echo_main;
+  uword *p;
+  DBG ("Got disonnected reply for session handle %lu", mp->handle);
+  em->state = STATE_START;
+
+  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
+  if (p)
+    hash_unset (em->session_index_by_vpp_handles, mp->handle);
+  else
+    clib_warning ("couldn't find session key %llx", mp->handle);
+
+  if (mp->retval)
+    clib_warning ("vpp complained about disconnect: %d", ntohl (mp->retval));
+}
+
+static void
+  vl_api_application_tls_cert_add_reply_t_handler
+  (vl_api_application_tls_cert_add_reply_t * mp)
+{
+  if (mp->retval)
+    clib_warning ("failed to add tls cert");
+}
+
+static void
+  vl_api_application_tls_key_add_reply_t_handler
+  (vl_api_application_tls_key_add_reply_t * mp)
+{
+  if (mp->retval)
+    clib_warning ("failed to add tls key");
+}
+
+#define foreach_quic_echo_msg                            		\
+_(BIND_URI_REPLY, bind_uri_reply)                       		\
+_(UNBIND_URI_REPLY, unbind_uri_reply)                   		\
+_(DISCONNECT_SESSION_REPLY, disconnect_session_reply)   		\
+_(APPLICATION_ATTACH_REPLY, application_attach_reply)   		\
+_(APPLICATION_DETACH_REPLY, application_detach_reply)			\
+_(MAP_ANOTHER_SEGMENT, map_another_segment)				\
+_(APPLICATION_TLS_CERT_ADD_REPLY, application_tls_cert_add_reply)	\
+_(APPLICATION_TLS_KEY_ADD_REPLY, application_tls_key_add_reply)		\
+
+void
+quic_echo_api_hookup (echo_main_t * em)
+{
+#define _(N,n)                                                  \
+    vl_msg_api_set_handlers(VL_API_##N, #n,                     \
+                           vl_api_##n##_t_handler,              \
+                           vl_noop_handler,                     \
+                           vl_api_##n##_t_endian,               \
+                           vl_api_##n##_t_print,                \
+                           sizeof(vl_api_##n##_t), 1);
+  foreach_quic_echo_msg;
+#undef _
+}
+
+static void
+print_usage_and_exit (void)
+{
+  fprintf (stderr,
+	   "quic_echo [socket-name SOCKET] [client|server] [uri URI] [OPTIONS]\n"
+	   "\n"
+	   "  socket-name PATH    Specify the binary socket path to connect to VPP\n"
+	   "  use-svm-api         Use SVM API to connect to VPP\n"
+	   "  test-bytes[:assert] Check data correctness when receiving (assert fails on first error)\n"
+	   "  fifo-size N         Use N Kb fifos\n"
+	   "  appns NAMESPACE     Use the namespace NAMESPACE\n"
+	   "  all-scope           all-scope option\n"
+	   "  local-scope         local-scope option\n"
+	   "  global-scope        global-scope option\n"
+	   "  secret SECRET       set namespace secret\n"
+	   "  chroot prefix PATH  Use PATH as memory root path\n"
+	   "  quic-setup OPT      OPT=serverstream : Client open N connections. On each one server opens M streams\n"
+	   "                            by default : Client open N connections. On each one client opens M streams\n"
+	   "\n"
+	   "  no-return            Drop the data when received, dont reply\n"
+	   "  nclients N[/M]       Open N QUIC connections, each one with M streams (M defaults to 1)\n"
+	   "  send N[Kb|Mb|GB]     Send N [K|M|G]bytes\n"
+	   "  recv N[Kb|Mb|GB]     Expect N [K|M|G]bytes\n"
+	   "  nclients N[/M]       Open N QUIC connections, each one with M streams (M defaults to 1)\n");
+  exit (1);
+}
+
+
+void
+quic_echo_process_opts (int argc, char **argv)
+{
+  echo_main_t *em = &echo_main;
+  unformat_input_t _argv, *a = &_argv;
+  u32 tmp;
+  u8 *chroot_prefix;
+  u8 *uri = 0;
+
+  unformat_init_command_line (a, argv);
+  while (unformat_check_input (a) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (a, "chroot prefix %s", &chroot_prefix))
+	{
+	  vl_set_memory_root_path ((char *) chroot_prefix);
+	}
+      else if (unformat (a, "uri %s", &uri))
+	em->uri = format (0, "%s%c", uri, 0);
+      else if (unformat (a, "server"))
+	em->i_am_master = 1;
+      else if (unformat (a, "client"))
+	em->i_am_master = 0;
+      else if (unformat (a, "no-return"))
+	em->no_return = 1;
+      else if (unformat (a, "test-bytes:assert"))
+	em->test_return_packets = RETURN_PACKETS_ASSERT;
+      else if (unformat (a, "test-bytes"))
+	em->test_return_packets = RETURN_PACKETS_LOG_WRONG;
+      else if (unformat (a, "socket-name %s", &em->socket_name))
+	;
+      else if (unformat (a, "use-svm-api"))
+	em->use_sock_api = 0;
+      else if (unformat (a, "fifo-size %d", &tmp))
+	em->fifo_size = tmp << 10;
+      else
+	if (unformat
+	    (a, "nclients %d/%d", &em->n_clients, &em->n_stream_clients))
+	;
+      else if (unformat (a, "nclients %d", &em->n_clients))
+	;
+      else if (unformat (a, "appns %_%v%_", &em->appns_id))
+	;
+      else if (unformat (a, "all-scope"))
+	em->appns_flags |= (APP_OPTIONS_FLAGS_USE_GLOBAL_SCOPE
+			    | APP_OPTIONS_FLAGS_USE_LOCAL_SCOPE);
+      else if (unformat (a, "local-scope"))
+	em->appns_flags = APP_OPTIONS_FLAGS_USE_LOCAL_SCOPE;
+      else if (unformat (a, "global-scope"))
+	em->appns_flags = APP_OPTIONS_FLAGS_USE_GLOBAL_SCOPE;
+      else if (unformat (a, "secret %lu", &em->appns_secret))
+	;
+      else if (unformat (a, "quic-setup %U", echo_unformat_quic_setup_vft))
+	;
+      else
+	if (unformat (a, "send %U", echo_unformat_data, &em->bytes_to_send))
+	;
+      else
+	if (unformat
+	    (a, "recv %U", echo_unformat_data, &em->bytes_to_receive))
+	;
+      else if (unformat (a, "time %U:%U",
+			 echo_unformat_timing_event, &em->timing_start_event,
+			 echo_unformat_timing_event, &em->timing_end_event))
+	;
+      else
+	print_usage_and_exit ();
+    }
+}
+
+int
+main (int argc, char **argv)
+{
+  echo_main_t *em = &echo_main;
+  fifo_segment_main_t *sm = &em->segment_main;
+  char *app_name;
+  int i, rv;
+  u32 n_clients;
+
+  clib_mem_init_thread_safe (0, 256 << 20);
+  clib_memset (em, 0, sizeof (*em));
+  em->session_index_by_vpp_handles = hash_create (0, sizeof (uword));
+  em->shared_segment_handles = hash_create (0, sizeof (uword));
+  em->my_pid = getpid ();
+  em->socket_name = format (0, "%s%c", API_SOCKET_FILE, 0);
+  em->use_sock_api = 1;
+  em->fifo_size = 64 << 10;
+  em->n_clients = 1;
+  em->n_stream_clients = 1;
+  em->max_test_msg = 50;
+  em->time_to_stop = 0;
+  em->i_am_master = 1;
+  em->test_return_packets = RETURN_PACKETS_NOTEST;
+  em->timing_start_event = ECHO_EVT_FIRST_QCONNECT;
+  em->timing_end_event = ECHO_EVT_LAST_BYTE;
+  em->bytes_to_receive = 64 << 10;
+  em->bytes_to_send = 64 << 10;
+  em->uri = format (0, "%s%c", "quic://0.0.0.0/1234", 0);
+  em->cb_vft = default_cb_vft;
+  quic_echo_process_opts (argc, argv);
+
+  n_clients = em->n_clients * em->n_stream_clients;
+  vec_validate (em->client_thread_handles, n_clients - 1);
+  vec_validate (em->thread_args, n_clients - 1);
+  clib_time_init (&em->clib_time);
+  init_error_string_table (em);
+  fifo_segment_main_init (sm, HIGH_SEGMENT_BASEVA, 20);
+  clib_spinlock_init (&em->segment_handles_lock);
+  vec_validate (em->rx_buf, 4 << 20);
+  vec_validate (em->connect_test_data, 1024 * 1024 - 1);
+  for (i = 0; i < vec_len (em->connect_test_data); i++)
+    em->connect_test_data[i] = i & 0xff;
+
+  setup_signal_handlers ();
+  quic_echo_api_hookup (em);
+
+  app_name = em->i_am_master ? "quic_echo_server" : "quic_echo_client";
+  if (connect_to_vpp (app_name) < 0)
+    {
+      svm_region_exit ();
+      fformat (stderr, "Couldn't connect to vpe, exiting...\n");
+      exit (1);
+    }
+
+  quic_echo_notify_event (em, ECHO_EVT_START);
+  if (em->i_am_master)
+    rv = server_run (em);
+  else
+    rv = clients_run (em);
+  if (rv)
+    exit (rv);
+  quic_echo_notify_event (em, ECHO_EVT_EXIT);
+  print_global_stats (em);
+
+  /* Make sure detach finishes */
+  if (wait_for_state_change (em, STATE_DETACHED, TIMEOUT))
+    exit (-1);
+  disconnect_from_vpp (em);
+  exit (0);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/hs_apps/tcp_echo.c b/src/plugins/hs_apps/tcp_echo.c
new file mode 100644
index 00000000000..6c3ce928490
--- /dev/null
+++ b/src/plugins/hs_apps/tcp_echo.c
@@ -0,0 +1,1414 @@
+/*
+ * Copyright (c) 2016 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:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <signal.h>
+
+#include <vnet/session/application_interface.h>
+#include <vlibmemory/api.h>
+
+#include <vpp/api/vpe_msg_enum.h>
+#include <svm/fifo_segment.h>
+
+#define vl_typedefs		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_typedefs
+
+/* declare message handlers for each api */
+
+#define vl_endianfun		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...)
+#define vl_printfun
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_printfun
+
+#define TCP_ECHO_DBG 0
+#define DBG(_fmt,_args...)			\
+    if (TCP_ECHO_DBG) 				\
+      clib_warning (_fmt, _args)
+
+typedef struct
+{
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+#define _(type, name) type name;
+  foreach_app_session_field
+#undef _
+  u64 vpp_session_handle;
+  u64 bytes_sent;
+  u64 bytes_to_send;
+  volatile u64 bytes_received;
+  volatile u64 bytes_to_receive;
+  f64 start;
+} echo_session_t;
+
+typedef enum
+{
+  STATE_START,
+  STATE_ATTACHED,
+  STATE_LISTEN,
+  STATE_READY,
+  STATE_DISCONNECTING,
+  STATE_FAILED,
+  STATE_DETACHED
+} connection_state_t;
+
+typedef struct
+{
+  /* vpe input queue */
+  svm_queue_t *vl_input_queue;
+
+  /* API client handle */
+  u32 my_client_index;
+
+  /* The URI we're playing with */
+  u8 *uri;
+
+  /* Session pool */
+  echo_session_t *sessions;
+
+  /* Hash table for disconnect processing */
+  uword *session_index_by_vpp_handles;
+
+  /* intermediate rx buffer */
+  u8 *rx_buf;
+
+  /* URI for slave's connect */
+  u8 *connect_uri;
+
+  u32 connected_session_index;
+
+  int i_am_master;
+
+  /* drop all packets */
+  int no_return;
+
+  /* Our event queue */
+  svm_msg_q_t *our_event_queue;
+
+  u8 *socket_name;
+
+  pid_t my_pid;
+
+  /* For deadman timers */
+  clib_time_t clib_time;
+
+  /* State of the connection, shared between msg RX thread and main thread */
+  volatile connection_state_t state;
+
+  /* Signal variables */
+  volatile int time_to_stop;
+  volatile int time_to_print_stats;
+
+  u32 configured_segment_size;
+
+  /* VNET_API_ERROR_FOO -> "Foo" hash table */
+  uword *error_string_by_error_number;
+
+  u8 *connect_test_data;
+  pthread_t *client_thread_handles;
+  u32 *thread_args;
+  u32 client_bytes_received;
+  u8 test_return_packets;
+  u64 bytes_to_send;
+  u32 fifo_size;
+
+  u32 n_clients;
+  u64 tx_total;
+  u64 rx_total;
+
+  volatile u32 n_clients_connected;
+  volatile u32 n_active_clients;
+
+
+  /** Flag that decides if socket, instead of svm, api is used to connect to
+   * vpp. If sock api is used, shm binary api is subsequently bootstrapped
+   * and all other messages are exchanged using shm IPC. */
+  u8 use_sock_api;
+
+  fifo_segment_main_t segment_main;
+} echo_main_t;
+
+echo_main_t echo_main;
+
+#if CLIB_DEBUG > 0
+#define NITER 10000
+#else
+#define NITER 4000000
+#endif
+
+static u8 *
+format_api_error (u8 * s, va_list * args)
+{
+  echo_main_t *em = &echo_main;
+  i32 error = va_arg (*args, u32);
+  uword *p;
+
+  p = hash_get (em->error_string_by_error_number, -error);
+
+  if (p)
+    s = format (s, "%s", p[0]);
+  else
+    s = format (s, "%d", error);
+  return s;
+}
+
+static void
+init_error_string_table (echo_main_t * em)
+{
+  em->error_string_by_error_number = hash_create (0, sizeof (uword));
+
+#define _(n,v,s) hash_set (em->error_string_by_error_number, -v, s);
+  foreach_vnet_api_error;
+#undef _
+
+  hash_set (em->error_string_by_error_number, 99, "Misc");
+}
+
+static void handle_mq_event (session_event_t * e);
+
+static int
+wait_for_state_change (echo_main_t * em, connection_state_t state)
+{
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+  f64 timeout;
+
+#if CLIB_DEBUG > 0
+#define TIMEOUT 600.0
+#else
+#define TIMEOUT 600.0
+#endif
+
+  timeout = clib_time_now (&em->clib_time) + TIMEOUT;
+
+  while (clib_time_now (&em->clib_time) < timeout)
+    {
+      if (em->state == state)
+	return 0;
+      if (em->state == STATE_FAILED)
+	return -1;
+      if (em->time_to_stop == 1)
+	return 0;
+      if (!em->our_event_queue || em->state < STATE_ATTACHED)
+	continue;
+
+      if (svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_NOWAIT, 0))
+	continue;
+      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+      handle_mq_event (e);
+      svm_msg_q_free_msg (em->our_event_queue, &msg);
+    }
+  clib_warning ("timeout waiting for state %d", state);
+  return -1;
+}
+
+void
+application_send_attach (echo_main_t * em)
+{
+  vl_api_application_attach_t *bmp;
+  vl_api_application_tls_cert_add_t *cert_mp;
+  vl_api_application_tls_key_add_t *key_mp;
+
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_APPLICATION_ATTACH);
+  bmp->client_index = em->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  bmp->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_ACCEPT_REDIRECT;
+  bmp->options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_ADD_SEGMENT;
+  bmp->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] = 16;
+  bmp->options[APP_OPTIONS_RX_FIFO_SIZE] = em->fifo_size;
+  bmp->options[APP_OPTIONS_TX_FIFO_SIZE] = em->fifo_size;
+  bmp->options[APP_OPTIONS_ADD_SEGMENT_SIZE] = 128 << 20;
+  bmp->options[APP_OPTIONS_SEGMENT_SIZE] = 256 << 20;
+  bmp->options[APP_OPTIONS_EVT_QUEUE_SIZE] = 256;
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & bmp);
+
+  cert_mp = vl_msg_api_alloc (sizeof (*cert_mp) + test_srv_crt_rsa_len);
+  clib_memset (cert_mp, 0, sizeof (*cert_mp));
+  cert_mp->_vl_msg_id = ntohs (VL_API_APPLICATION_TLS_CERT_ADD);
+  cert_mp->client_index = em->my_client_index;
+  cert_mp->context = ntohl (0xfeedface);
+  cert_mp->cert_len = clib_host_to_net_u16 (test_srv_crt_rsa_len);
+  clib_memcpy_fast (cert_mp->cert, test_srv_crt_rsa, test_srv_crt_rsa_len);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & cert_mp);
+
+  key_mp = vl_msg_api_alloc (sizeof (*key_mp) + test_srv_key_rsa_len);
+  clib_memset (key_mp, 0, sizeof (*key_mp) + test_srv_key_rsa_len);
+  key_mp->_vl_msg_id = ntohs (VL_API_APPLICATION_TLS_KEY_ADD);
+  key_mp->client_index = em->my_client_index;
+  key_mp->context = ntohl (0xfeedface);
+  key_mp->key_len = clib_host_to_net_u16 (test_srv_key_rsa_len);
+  clib_memcpy_fast (key_mp->key, test_srv_key_rsa, test_srv_key_rsa_len);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & key_mp);
+}
+
+static int
+application_attach (echo_main_t * em)
+{
+  application_send_attach (em);
+  if (wait_for_state_change (em, STATE_ATTACHED))
+    {
+      clib_warning ("timeout waiting for STATE_ATTACHED");
+      return -1;
+    }
+  return 0;
+}
+
+void
+application_detach (echo_main_t * em)
+{
+  vl_api_application_detach_t *bmp;
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_APPLICATION_DETACH);
+  bmp->client_index = em->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & bmp);
+
+  DBG ("%s", "Sent detach");
+}
+
+static int
+ssvm_segment_attach (char *name, ssvm_segment_type_t type, int fd)
+{
+  fifo_segment_create_args_t _a, *a = &_a;
+  fifo_segment_main_t *sm = &echo_main.segment_main;
+  int rv;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->segment_name = (char *) name;
+  a->segment_type = type;
+
+  if (type == SSVM_SEGMENT_MEMFD)
+    a->memfd_fd = fd;
+
+  if ((rv = fifo_segment_attach (sm, a)))
+    {
+      clib_warning ("svm_fifo_segment_attach ('%s') failed", name);
+      return rv;
+    }
+
+  vec_reset_length (a->new_segment_indices);
+  return 0;
+}
+
+static void
+vl_api_application_attach_reply_t_handler (vl_api_application_attach_reply_t *
+					   mp)
+{
+  echo_main_t *em = &echo_main;
+  int *fds = 0;
+  u32 n_fds = 0;
+
+  if (mp->retval)
+    {
+      clib_warning ("attach failed: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      goto failed;
+    }
+
+  if (mp->segment_name_length == 0)
+    {
+      clib_warning ("segment_name_length zero");
+      goto failed;
+    }
+
+  ASSERT (mp->app_event_queue_address);
+  em->our_event_queue = uword_to_pointer (mp->app_event_queue_address,
+					  svm_msg_q_t *);
+
+  if (mp->n_fds)
+    {
+      vec_validate (fds, mp->n_fds);
+      vl_socket_client_recv_fd_msg (fds, mp->n_fds, 5);
+
+      if (mp->fd_flags & SESSION_FD_F_VPP_MQ_SEGMENT)
+	if (ssvm_segment_attach (0, SSVM_SEGMENT_MEMFD, fds[n_fds++]))
+	  goto failed;
+
+      if (mp->fd_flags & SESSION_FD_F_MEMFD_SEGMENT)
+	if (ssvm_segment_attach ((char *) mp->segment_name,
+				 SSVM_SEGMENT_MEMFD, fds[n_fds++]))
+	  goto failed;
+
+      if (mp->fd_flags & SESSION_FD_F_MQ_EVENTFD)
+	svm_msg_q_set_consumer_eventfd (em->our_event_queue, fds[n_fds++]);
+
+      vec_free (fds);
+    }
+  else
+    {
+      if (ssvm_segment_attach ((char *) mp->segment_name, SSVM_SEGMENT_SHM,
+			       -1))
+	goto failed;
+    }
+
+  em->state = STATE_ATTACHED;
+  return;
+failed:
+  em->state = STATE_FAILED;
+  return;
+}
+
+static void
+vl_api_application_detach_reply_t_handler (vl_api_application_detach_reply_t *
+					   mp)
+{
+  if (mp->retval)
+    clib_warning ("detach returned with err: %d", mp->retval);
+  echo_main.state = STATE_DETACHED;
+}
+
+static void
+stop_signal (int signum)
+{
+  echo_main_t *um = &echo_main;
+
+  um->time_to_stop = 1;
+}
+
+static void
+stats_signal (int signum)
+{
+  echo_main_t *um = &echo_main;
+
+  um->time_to_print_stats = 1;
+}
+
+static clib_error_t *
+setup_signal_handlers (void)
+{
+  signal (SIGINT, stats_signal);
+  signal (SIGQUIT, stop_signal);
+  signal (SIGTERM, stop_signal);
+
+  return 0;
+}
+
+void
+vlib_cli_output (struct vlib_main_t *vm, char *fmt, ...)
+{
+  clib_warning ("BUG");
+}
+
+int
+connect_to_vpp (char *name)
+{
+  echo_main_t *em = &echo_main;
+  api_main_t *am = &api_main;
+
+  if (em->use_sock_api)
+    {
+      if (vl_socket_client_connect ((char *) em->socket_name, name,
+				    0 /* default rx, tx buffer */ ))
+	{
+	  clib_warning ("socket connect failed");
+	  return -1;
+	}
+
+      if (vl_socket_client_init_shm (0, 1 /* want_pthread */ ))
+	{
+	  clib_warning ("init shm api failed");
+	  return -1;
+	}
+    }
+  else
+    {
+      if (vl_client_connect_to_vlib ("/vpe-api", name, 32) < 0)
+	{
+	  clib_warning ("shmem connect failed");
+	  return -1;
+	}
+    }
+  em->vl_input_queue = am->shmem_hdr->vl_input_queue;
+  em->my_client_index = am->my_client_index;
+  return 0;
+}
+
+void
+disconnect_from_vpp (echo_main_t * em)
+{
+  if (em->use_sock_api)
+    vl_socket_client_disconnect ();
+  else
+    vl_client_disconnect_from_vlib ();
+}
+
+static void
+vl_api_map_another_segment_t_handler (vl_api_map_another_segment_t * mp)
+{
+  fifo_segment_main_t *sm = &echo_main.segment_main;
+  fifo_segment_create_args_t _a, *a = &_a;
+  int rv;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->segment_name = (char *) mp->segment_name;
+  a->segment_size = mp->segment_size;
+  /* Attach to the segment vpp created */
+  rv = fifo_segment_attach (sm, a);
+  if (rv)
+    {
+      clib_warning ("svm_fifo_segment_attach ('%s') failed",
+		    mp->segment_name);
+      return;
+    }
+  clib_warning ("Mapped new segment '%s' size %d", mp->segment_name,
+		mp->segment_size);
+}
+
+static void
+session_print_stats (echo_main_t * em, echo_session_t * session)
+{
+  f64 deltat;
+  u64 bytes;
+
+  deltat = clib_time_now (&em->clib_time) - session->start;
+  bytes = em->i_am_master ? session->bytes_received : em->bytes_to_send;
+  fformat (stdout, "Finished in %.6f\n", deltat);
+  fformat (stdout, "%.4f Gbit/second\n", (bytes * 8.0) / deltat / 1e9);
+}
+
+static void
+test_recv_bytes (echo_session_t * s, u8 * rx_buf, u32 n_read)
+{
+  int i;
+  for (i = 0; i < n_read; i++)
+    {
+      if (rx_buf[i] != ((s->bytes_received + i) & 0xff))
+	{
+	  clib_warning ("error at byte %lld, 0x%x not 0x%x",
+			s->bytes_received + i, rx_buf[i],
+			((s->bytes_received + i) & 0xff));
+	}
+    }
+}
+
+static void
+recv_data_chunk (echo_main_t * em, echo_session_t * s, u8 * rx_buf)
+{
+  int n_to_read, n_read;
+
+  n_to_read = svm_fifo_max_dequeue_cons (s->rx_fifo);
+  if (!n_to_read)
+    return;
+
+  do
+    {
+      n_read = app_recv_stream ((app_session_t *) s, rx_buf,
+				vec_len (rx_buf));
+
+      if (n_read > 0)
+	{
+	  if (em->test_return_packets)
+	    test_recv_bytes (s, rx_buf, n_read);
+
+	  n_to_read -= n_read;
+
+	  s->bytes_received += n_read;
+	  s->bytes_to_receive -= n_read;
+	}
+      else
+	break;
+    }
+  while (n_to_read > 0);
+}
+
+static void
+send_data_chunk (echo_main_t * em, echo_session_t * s)
+{
+  u64 test_buf_len, bytes_this_chunk, test_buf_offset;
+  u8 *test_data = em->connect_test_data;
+  int n_sent;
+
+  test_buf_len = vec_len (test_data);
+  test_buf_offset = s->bytes_sent % test_buf_len;
+  bytes_this_chunk = clib_min (test_buf_len - test_buf_offset,
+			       s->bytes_to_send);
+
+  n_sent = app_send_stream ((app_session_t *) s, test_data + test_buf_offset,
+			    bytes_this_chunk, 0);
+
+  if (n_sent > 0)
+    {
+      s->bytes_to_send -= n_sent;
+      s->bytes_sent += n_sent;
+    }
+}
+
+/*
+ * Rx/Tx polling thread per connection
+ */
+static void *
+client_thread_fn (void *arg)
+{
+  echo_main_t *em = &echo_main;
+  static u8 *rx_buf = 0;
+  u32 session_index = *(u32 *) arg;
+  echo_session_t *s;
+
+  vec_validate (rx_buf, 1 << 20);
+
+  while (!em->time_to_stop && em->state != STATE_READY)
+    ;
+
+  s = pool_elt_at_index (em->sessions, session_index);
+  while (!em->time_to_stop)
+    {
+      send_data_chunk (em, s);
+      recv_data_chunk (em, s, rx_buf);
+      if (!s->bytes_to_send && !s->bytes_to_receive)
+	break;
+    }
+
+  DBG ("session %d done", session_index);
+  em->tx_total += s->bytes_sent;
+  em->rx_total += s->bytes_received;
+  em->n_active_clients--;
+
+  pthread_exit (0);
+}
+
+void
+client_send_connect (echo_main_t * em)
+{
+  vl_api_connect_uri_t *cmp;
+  cmp = vl_msg_api_alloc (sizeof (*cmp));
+  clib_memset (cmp, 0, sizeof (*cmp));
+
+  cmp->_vl_msg_id = ntohs (VL_API_CONNECT_URI);
+  cmp->client_index = em->my_client_index;
+  cmp->context = ntohl (0xfeedface);
+  memcpy (cmp->uri, em->connect_uri, vec_len (em->connect_uri));
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & cmp);
+}
+
+void
+client_send_disconnect (echo_main_t * em, echo_session_t * s)
+{
+  vl_api_disconnect_session_t *dmp;
+  dmp = vl_msg_api_alloc (sizeof (*dmp));
+  clib_memset (dmp, 0, sizeof (*dmp));
+  dmp->_vl_msg_id = ntohs (VL_API_DISCONNECT_SESSION);
+  dmp->client_index = em->my_client_index;
+  dmp->handle = s->vpp_session_handle;
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & dmp);
+}
+
+int
+client_disconnect (echo_main_t * em, echo_session_t * s)
+{
+  client_send_disconnect (em, s);
+  pool_put (em->sessions, s);
+  clib_memset (s, 0xfe, sizeof (*s));
+  return 0;
+}
+
+static void
+session_bound_handler (session_bound_msg_t * mp)
+{
+  echo_main_t *em = &echo_main;
+
+  if (mp->retval)
+    {
+      clib_warning ("bind failed: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      em->state = STATE_FAILED;
+      return;
+    }
+
+  clib_warning ("listening on %U:%u", format_ip46_address, mp->lcl_ip,
+		mp->lcl_is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6, mp->lcl_port);
+  em->state = STATE_READY;
+}
+
+static void
+session_accepted_handler (session_accepted_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  session_accepted_reply_msg_t *rmp;
+  svm_fifo_t *rx_fifo, *tx_fifo;
+  echo_main_t *em = &echo_main;
+  echo_session_t *session;
+  static f64 start_time;
+  u32 session_index;
+  u8 *ip_str;
+
+  if (start_time == 0.0)
+    start_time = clib_time_now (&em->clib_time);
+
+  ip_str = format (0, "%U", format_ip46_address, &mp->rmt.ip, mp->rmt.is_ip4);
+  clib_warning ("Accepted session from: %s:%d", ip_str,
+		clib_net_to_host_u16 (mp->rmt.port));
+
+  /* Allocate local session and set it up */
+  pool_get (em->sessions, session);
+  session_index = session - em->sessions;
+
+  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  rx_fifo->client_session_index = session_index;
+  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+  tx_fifo->client_session_index = session_index;
+
+  session->rx_fifo = rx_fifo;
+  session->tx_fifo = tx_fifo;
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					 svm_msg_q_t *);
+
+  /* Add it to lookup table */
+  hash_set (em->session_index_by_vpp_handles, mp->handle, session_index);
+
+  em->state = STATE_READY;
+
+  /* Stats printing */
+  if (pool_elts (em->sessions) && (pool_elts (em->sessions) % 20000) == 0)
+    {
+      f64 now = clib_time_now (&em->clib_time);
+      fformat (stdout, "%d active sessions in %.2f seconds, %.2f/sec...\n",
+	       pool_elts (em->sessions), now - start_time,
+	       (f64) pool_elts (em->sessions) / (now - start_time));
+    }
+
+  /*
+   * Send accept reply to vpp
+   */
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_ACCEPTED_REPLY);
+  rmp = (session_accepted_reply_msg_t *) app_evt->evt->data;
+  rmp->handle = mp->handle;
+  rmp->context = mp->context;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+
+  session->bytes_received = 0;
+  session->start = clib_time_now (&em->clib_time);
+}
+
+static void
+session_connected_handler (session_connected_msg_t * mp)
+{
+  echo_main_t *em = &echo_main;
+  echo_session_t *session;
+  u32 session_index;
+  svm_fifo_t *rx_fifo, *tx_fifo;
+  int rv;
+
+  if (mp->retval)
+    {
+      clib_warning ("connection failed with code: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      em->state = STATE_FAILED;
+      return;
+    }
+
+  /*
+   * Setup session
+   */
+
+  pool_get (em->sessions, session);
+  clib_memset (session, 0, sizeof (*session));
+  session_index = session - em->sessions;
+
+  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  rx_fifo->client_session_index = session_index;
+  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+  tx_fifo->client_session_index = session_index;
+
+  session->rx_fifo = rx_fifo;
+  session->tx_fifo = tx_fifo;
+  session->vpp_session_handle = mp->handle;
+  session->start = clib_time_now (&em->clib_time);
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					 svm_msg_q_t *);
+
+  hash_set (em->session_index_by_vpp_handles, mp->handle, session_index);
+
+  /*
+   * Start RX thread
+   */
+  em->thread_args[em->n_clients_connected] = session_index;
+  rv = pthread_create (&em->client_thread_handles[em->n_clients_connected],
+		       NULL /*attr */ , client_thread_fn,
+		       (void *) &em->thread_args[em->n_clients_connected]);
+  if (rv)
+    {
+      clib_warning ("pthread_create returned %d", rv);
+      return;
+    }
+
+  em->n_clients_connected += 1;
+  clib_warning ("session %u (0x%llx) connected with local ip %U port %d",
+		session_index, mp->handle, format_ip46_address, &mp->lcl.ip,
+		mp->lcl.is_ip4, clib_net_to_host_u16 (mp->lcl.port));
+}
+
+static void
+session_disconnected_handler (session_disconnected_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  session_disconnected_reply_msg_t *rmp;
+  echo_main_t *em = &echo_main;
+  echo_session_t *session = 0;
+  uword *p;
+  int rv = 0;
+
+  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
+  if (!p)
+    {
+      clib_warning ("couldn't find session key %llx", mp->handle);
+      return;
+    }
+
+  session = pool_elt_at_index (em->sessions, p[0]);
+  hash_unset (em->session_index_by_vpp_handles, mp->handle);
+  pool_put (em->sessions, session);
+
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_DISCONNECTED_REPLY);
+  rmp = (session_disconnected_reply_msg_t *) app_evt->evt->data;
+  rmp->retval = rv;
+  rmp->handle = mp->handle;
+  rmp->context = mp->context;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+
+  session_print_stats (em, session);
+}
+
+static void
+session_reset_handler (session_reset_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  echo_main_t *em = &echo_main;
+  session_reset_reply_msg_t *rmp;
+  echo_session_t *session = 0;
+  uword *p;
+  int rv = 0;
+
+  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
+
+  if (p)
+    {
+      session = pool_elt_at_index (em->sessions, p[0]);
+      clib_warning ("got reset");
+      /* Cleanup later */
+      em->time_to_stop = 1;
+    }
+  else
+    {
+      clib_warning ("couldn't find session key %llx", mp->handle);
+      return;
+    }
+
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_RESET_REPLY);
+  rmp = (session_reset_reply_msg_t *) app_evt->evt->data;
+  rmp->retval = rv;
+  rmp->handle = mp->handle;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+}
+
+static void
+handle_mq_event (session_event_t * e)
+{
+  switch (e->event_type)
+    {
+    case SESSION_CTRL_EVT_BOUND:
+      session_bound_handler ((session_bound_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_ACCEPTED:
+      session_accepted_handler ((session_accepted_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_CONNECTED:
+      session_connected_handler ((session_connected_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED:
+      session_disconnected_handler ((session_disconnected_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_RESET:
+      session_reset_handler ((session_reset_msg_t *) e->data);
+      break;
+    default:
+      clib_warning ("unhandled %u", e->event_type);
+    }
+}
+
+static void
+clients_run (echo_main_t * em)
+{
+  f64 start_time, deltat, timeout = 100.0;
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+  echo_session_t *s;
+  int i;
+
+  /* Init test data */
+  vec_validate (em->connect_test_data, 1024 * 1024 - 1);
+  for (i = 0; i < vec_len (em->connect_test_data); i++)
+    em->connect_test_data[i] = i & 0xff;
+
+  /*
+   * Attach and connect the clients
+   */
+  if (application_attach (em))
+    return;
+
+  for (i = 0; i < em->n_clients; i++)
+    client_send_connect (em);
+
+  start_time = clib_time_now (&em->clib_time);
+  while (em->n_clients_connected < em->n_clients
+	 && (clib_time_now (&em->clib_time) - start_time < timeout)
+	 && em->state != STATE_FAILED)
+
+    {
+      svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_WAIT, 0);
+      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+      handle_mq_event (e);
+      svm_msg_q_free_msg (em->our_event_queue, &msg);
+    }
+
+  if (em->n_clients_connected != em->n_clients)
+    {
+      clib_warning ("failed to initialize all connections");
+      return;
+    }
+
+  /*
+   * Initialize connections
+   */
+  for (i = 0; i < em->n_clients; i++)
+    {
+      s = pool_elt_at_index (em->sessions, i);
+      s->bytes_to_send = em->bytes_to_send;
+      if (!em->no_return)
+	s->bytes_to_receive = em->bytes_to_send;
+    }
+  em->n_active_clients = em->n_clients_connected;
+
+  /*
+   * Wait for client threads to send the data
+   */
+  start_time = clib_time_now (&em->clib_time);
+  em->state = STATE_READY;
+  while (em->n_active_clients)
+    if (!svm_msg_q_is_empty (em->our_event_queue))
+      {
+	if (svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_WAIT, 0))
+	  {
+	    clib_warning ("svm msg q returned");
+	    continue;
+	  }
+	e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+	if (e->event_type != SESSION_IO_EVT_RX)
+	  handle_mq_event (e);
+	svm_msg_q_free_msg (em->our_event_queue, &msg);
+      }
+
+  for (i = 0; i < em->n_clients; i++)
+    {
+      s = pool_elt_at_index (em->sessions, i);
+      client_disconnect (em, s);
+    }
+
+  /*
+   * Stats and detach
+   */
+  deltat = clib_time_now (&em->clib_time) - start_time;
+  fformat (stdout, "%lld bytes (%lld mbytes, %lld gbytes) in %.2f seconds\n",
+	   em->tx_total, em->tx_total / (1ULL << 20),
+	   em->tx_total / (1ULL << 30), deltat);
+  fformat (stdout, "%.4f Gbit/second\n", (em->tx_total * 8.0) / deltat / 1e9);
+
+  application_detach (em);
+}
+
+static void
+vl_api_bind_uri_reply_t_handler (vl_api_bind_uri_reply_t * mp)
+{
+  echo_main_t *em = &echo_main;
+
+  if (mp->retval)
+    {
+      clib_warning ("bind failed: %U", format_api_error,
+		    clib_net_to_host_u32 (mp->retval));
+      em->state = STATE_FAILED;
+      return;
+    }
+
+  em->state = STATE_READY;
+}
+
+static void
+vl_api_unbind_uri_reply_t_handler (vl_api_unbind_uri_reply_t * mp)
+{
+  echo_main_t *em = &echo_main;
+
+  if (mp->retval != 0)
+    clib_warning ("returned %d", ntohl (mp->retval));
+
+  em->state = STATE_START;
+}
+
+u8 *
+format_ip4_address (u8 * s, va_list * args)
+{
+  u8 *a = va_arg (*args, u8 *);
+  return format (s, "%d.%d.%d.%d", a[0], a[1], a[2], a[3]);
+}
+
+u8 *
+format_ip6_address (u8 * s, va_list * args)
+{
+  ip6_address_t *a = va_arg (*args, ip6_address_t *);
+  u32 i, i_max_n_zero, max_n_zeros, i_first_zero, n_zeros, last_double_colon;
+
+  i_max_n_zero = ARRAY_LEN (a->as_u16);
+  max_n_zeros = 0;
+  i_first_zero = i_max_n_zero;
+  n_zeros = 0;
+  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
+    {
+      u32 is_zero = a->as_u16[i] == 0;
+      if (is_zero && i_first_zero >= ARRAY_LEN (a->as_u16))
+	{
+	  i_first_zero = i;
+	  n_zeros = 0;
+	}
+      n_zeros += is_zero;
+      if ((!is_zero && n_zeros > max_n_zeros)
+	  || (i + 1 >= ARRAY_LEN (a->as_u16) && n_zeros > max_n_zeros))
+	{
+	  i_max_n_zero = i_first_zero;
+	  max_n_zeros = n_zeros;
+	  i_first_zero = ARRAY_LEN (a->as_u16);
+	  n_zeros = 0;
+	}
+    }
+
+  last_double_colon = 0;
+  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
+    {
+      if (i == i_max_n_zero && max_n_zeros > 1)
+	{
+	  s = format (s, "::");
+	  i += max_n_zeros - 1;
+	  last_double_colon = 1;
+	}
+      else
+	{
+	  s = format (s, "%s%x",
+		      (last_double_colon || i == 0) ? "" : ":",
+		      clib_net_to_host_u16 (a->as_u16[i]));
+	  last_double_colon = 0;
+	}
+    }
+
+  return s;
+}
+
+/* Format an IP46 address. */
+u8 *
+format_ip46_address (u8 * s, va_list * args)
+{
+  ip46_address_t *ip46 = va_arg (*args, ip46_address_t *);
+  ip46_type_t type = va_arg (*args, ip46_type_t);
+  int is_ip4 = 1;
+
+  switch (type)
+    {
+    case IP46_TYPE_ANY:
+      is_ip4 = ip46_address_is_ip4 (ip46);
+      break;
+    case IP46_TYPE_IP4:
+      is_ip4 = 1;
+      break;
+    case IP46_TYPE_IP6:
+      is_ip4 = 0;
+      break;
+    }
+
+  return is_ip4 ?
+    format (s, "%U", format_ip4_address, &ip46->ip4) :
+    format (s, "%U", format_ip6_address, &ip46->ip6);
+}
+
+static void
+server_handle_rx (echo_main_t * em, session_event_t * e)
+{
+  int n_read, max_dequeue, n_sent;
+  u32 offset, to_dequeue;
+  echo_session_t *s;
+
+  s = pool_elt_at_index (em->sessions, e->session_index);
+
+  /* Clear event only once. Otherwise, if we do it in the loop by calling
+   * app_recv_stream, we may end up with a lot of unhandled rx events on the
+   * message queue */
+  svm_fifo_unset_event (s->rx_fifo);
+
+  max_dequeue = svm_fifo_max_dequeue_cons (s->rx_fifo);
+  if (PREDICT_FALSE (!max_dequeue))
+    return;
+
+  do
+    {
+      /* The options here are to limit ourselves to max_dequeue or read
+       * even the data that was enqueued while we were dequeueing and which
+       * now has an rx event in the mq. Either of the two work. */
+      to_dequeue = clib_min (max_dequeue, vec_len (em->rx_buf));
+      n_read = app_recv_stream_raw (s->rx_fifo, em->rx_buf, to_dequeue,
+				    0 /* clear evt */ , 0 /* peek */ );
+      if (n_read > 0)
+	{
+	  max_dequeue -= n_read;
+	  s->bytes_received += n_read;
+	}
+      else
+	break;
+
+      /* Reflect if a non-drop session */
+      if (!em->no_return && n_read > 0)
+	{
+	  offset = 0;
+	  do
+	    {
+	      n_sent = app_send_stream ((app_session_t *) s,
+					&em->rx_buf[offset],
+					n_read, SVM_Q_WAIT);
+	      if (n_sent > 0)
+		{
+		  n_read -= n_sent;
+		  offset += n_sent;
+		}
+	    }
+	  while ((n_sent <= 0 || n_read > 0) && !em->time_to_stop);
+	}
+    }
+  while (max_dequeue > 0 && !em->time_to_stop);
+}
+
+static void
+server_handle_mq (echo_main_t * em)
+{
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+
+  while (1)
+    {
+      svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_WAIT, 0);
+      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+      switch (e->event_type)
+	{
+	case SESSION_IO_EVT_RX:
+	  server_handle_rx (em, e);
+	  break;
+	default:
+	  handle_mq_event (e);
+	  break;
+	}
+      if (PREDICT_FALSE (em->time_to_stop == 1))
+	break;
+      if (PREDICT_FALSE (em->time_to_print_stats == 1))
+	{
+	  em->time_to_print_stats = 0;
+	  fformat (stdout, "%d connections\n", pool_elts (em->sessions));
+	}
+      svm_msg_q_free_msg (em->our_event_queue, &msg);
+    }
+}
+
+void
+server_send_listen (echo_main_t * em)
+{
+  vl_api_bind_uri_t *bmp;
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_BIND_URI);
+  bmp->client_index = em->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  memcpy (bmp->uri, em->uri, vec_len (em->uri));
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & bmp);
+}
+
+int
+server_listen (echo_main_t * em)
+{
+  server_send_listen (em);
+  if (wait_for_state_change (em, STATE_READY))
+    {
+      clib_warning ("timeout waiting for STATE_READY");
+      return -1;
+    }
+  return 0;
+}
+
+void
+server_send_unbind (echo_main_t * em)
+{
+  vl_api_unbind_uri_t *ump;
+
+  ump = vl_msg_api_alloc (sizeof (*ump));
+  clib_memset (ump, 0, sizeof (*ump));
+
+  ump->_vl_msg_id = ntohs (VL_API_UNBIND_URI);
+  ump->client_index = em->my_client_index;
+  memcpy (ump->uri, em->uri, vec_len (em->uri));
+  vl_msg_api_send_shmem (em->vl_input_queue, (u8 *) & ump);
+}
+
+int
+server_unbind (echo_main_t * em)
+{
+  server_send_unbind (em);
+  if (wait_for_state_change (em, STATE_START))
+    {
+      clib_warning ("timeout waiting for STATE_START");
+      return -1;
+    }
+  return 0;
+}
+
+void
+server_run (echo_main_t * em)
+{
+  echo_session_t *session;
+  int i;
+
+  /* $$$$ hack preallocation */
+  for (i = 0; i < 200000; i++)
+    {
+      pool_get (em->sessions, session);
+      clib_memset (session, 0, sizeof (*session));
+    }
+  for (i = 0; i < 200000; i++)
+    pool_put_index (em->sessions, i);
+
+  if (application_attach (em))
+    return;
+
+  /* Bind to uri */
+  if (server_listen (em))
+    return;
+
+  /* Enter handle event loop */
+  server_handle_mq (em);
+
+  /* Cleanup */
+  server_send_unbind (em);
+
+  application_detach (em);
+
+  fformat (stdout, "Test complete...\n");
+}
+
+static void
+vl_api_disconnect_session_reply_t_handler (vl_api_disconnect_session_reply_t *
+					   mp)
+{
+  echo_main_t *em = &echo_main;
+  uword *p;
+
+  if (mp->retval)
+    {
+      clib_warning ("vpp complained about disconnect: %d",
+		    ntohl (mp->retval));
+      return;
+    }
+
+  em->state = STATE_START;
+
+  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
+  if (p)
+    {
+      hash_unset (em->session_index_by_vpp_handles, mp->handle);
+    }
+  else
+    {
+      clib_warning ("couldn't find session key %llx", mp->handle);
+    }
+}
+
+static void
+  vl_api_application_tls_cert_add_reply_t_handler
+  (vl_api_application_tls_cert_add_reply_t * mp)
+{
+  if (mp->retval)
+    clib_warning ("failed to add tls cert");
+}
+
+static void
+  vl_api_application_tls_key_add_reply_t_handler
+  (vl_api_application_tls_key_add_reply_t * mp)
+{
+  if (mp->retval)
+    clib_warning ("failed to add tls key");
+}
+
+#define foreach_tcp_echo_msg                            		\
+_(BIND_URI_REPLY, bind_uri_reply)                       		\
+_(UNBIND_URI_REPLY, unbind_uri_reply)                   		\
+_(DISCONNECT_SESSION_REPLY, disconnect_session_reply)   		\
+_(APPLICATION_ATTACH_REPLY, application_attach_reply)   		\
+_(APPLICATION_DETACH_REPLY, application_detach_reply)			\
+_(MAP_ANOTHER_SEGMENT, map_another_segment)				\
+_(APPLICATION_TLS_CERT_ADD_REPLY, application_tls_cert_add_reply)	\
+_(APPLICATION_TLS_KEY_ADD_REPLY, application_tls_key_add_reply)		\
+
+void
+tcp_echo_api_hookup (echo_main_t * em)
+{
+#define _(N,n)                                                  \
+    vl_msg_api_set_handlers(VL_API_##N, #n,                     \
+                           vl_api_##n##_t_handler,              \
+                           vl_noop_handler,                     \
+                           vl_api_##n##_t_endian,               \
+                           vl_api_##n##_t_print,                \
+                           sizeof(vl_api_##n##_t), 1);
+  foreach_tcp_echo_msg;
+#undef _
+}
+
+int
+main (int argc, char **argv)
+{
+  int i_am_server = 1, test_return_packets = 0;
+  echo_main_t *em = &echo_main;
+  fifo_segment_main_t *sm = &em->segment_main;
+  unformat_input_t _argv, *a = &_argv;
+  u8 *chroot_prefix;
+  u8 *uri = 0;
+  u8 *bind_uri = (u8 *) "tcp://0.0.0.0/1234";
+  u8 *connect_uri = (u8 *) "tcp://6.0.1.1/1234";
+  u64 bytes_to_send = 64 << 10, mbytes;
+  char *app_name;
+  u32 tmp;
+
+  clib_mem_init_thread_safe (0, 256 << 20);
+
+  clib_memset (em, 0, sizeof (*em));
+  em->session_index_by_vpp_handles = hash_create (0, sizeof (uword));
+  em->my_pid = getpid ();
+  em->configured_segment_size = 1 << 20;
+  em->socket_name = 0;
+  em->use_sock_api = 1;
+  em->fifo_size = 64 << 10;
+  em->n_clients = 1;
+
+  clib_time_init (&em->clib_time);
+  init_error_string_table (em);
+  fifo_segment_main_init (sm, HIGH_SEGMENT_BASEVA, 20);
+  unformat_init_command_line (a, argv);
+
+  while (unformat_check_input (a) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (a, "chroot prefix %s", &chroot_prefix))
+	{
+	  vl_set_memory_root_path ((char *) chroot_prefix);
+	}
+      else if (unformat (a, "uri %s", &uri))
+	;
+      else if (unformat (a, "segment-size %dM", &tmp))
+	em->configured_segment_size = tmp << 20;
+      else if (unformat (a, "segment-size %dG", &tmp))
+	em->configured_segment_size = tmp << 30;
+      else if (unformat (a, "server"))
+	i_am_server = 1;
+      else if (unformat (a, "client"))
+	i_am_server = 0;
+      else if (unformat (a, "no-return"))
+	em->no_return = 1;
+      else if (unformat (a, "test"))
+	test_return_packets = 1;
+      else if (unformat (a, "mbytes %lld", &mbytes))
+	{
+	  bytes_to_send = mbytes << 20;
+	}
+      else if (unformat (a, "gbytes %lld", &mbytes))
+	{
+	  bytes_to_send = mbytes << 30;
+	}
+      else if (unformat (a, "socket-name %s", &em->socket_name))
+	;
+      else if (unformat (a, "use-svm-api"))
+	em->use_sock_api = 0;
+      else if (unformat (a, "fifo-size %d", &tmp))
+	em->fifo_size = tmp << 10;
+      else if (unformat (a, "nclients %d", &em->n_clients))
+	;
+      else
+	{
+	  fformat (stderr, "%s: usage [master|slave]\n", argv[0]);
+	  exit (1);
+	}
+    }
+
+  if (!em->socket_name)
+    em->socket_name = format (0, "%s%c", API_SOCKET_FILE, 0);
+
+  if (uri)
+    {
+      em->uri = format (0, "%s%c", uri, 0);
+      em->connect_uri = format (0, "%s%c", uri, 0);
+    }
+  else
+    {
+      em->uri = format (0, "%s%c", bind_uri, 0);
+      em->connect_uri = format (0, "%s%c", connect_uri, 0);
+    }
+
+  em->i_am_master = i_am_server;
+  em->test_return_packets = test_return_packets;
+  em->bytes_to_send = bytes_to_send;
+  em->time_to_stop = 0;
+  vec_validate (em->rx_buf, 4 << 20);
+  vec_validate (em->client_thread_handles, em->n_clients - 1);
+  vec_validate (em->thread_args, em->n_clients - 1);
+
+  setup_signal_handlers ();
+  tcp_echo_api_hookup (em);
+
+  app_name = i_am_server ? "tcp_echo_server" : "tcp_echo_client";
+  if (connect_to_vpp (app_name) < 0)
+    {
+      svm_region_exit ();
+      fformat (stderr, "Couldn't connect to vpe, exiting...\n");
+      exit (1);
+    }
+
+  if (i_am_server == 0)
+    clients_run (em);
+  else
+    server_run (em);
+
+  /* Make sure detach finishes */
+  wait_for_state_change (em, STATE_DETACHED);
+
+  disconnect_from_vpp (em);
+  exit (0);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/hs_apps/udp_echo.c b/src/plugins/hs_apps/udp_echo.c
new file mode 100644
index 00000000000..c9992befe98
--- /dev/null
+++ b/src/plugins/hs_apps/udp_echo.c
@@ -0,0 +1,1256 @@
+/*
+ * Copyright (c) 2016 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:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <setjmp.h>
+#include <signal.h>
+#include <vppinfra/clib.h>
+#include <vppinfra/format.h>
+#include <vppinfra/error.h>
+#include <vppinfra/time.h>
+#include <vppinfra/macros.h>
+#include <vnet/vnet.h>
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlibapi/api.h>
+#include <vlibmemory/api.h>
+#include <vpp/api/vpe_msg_enum.h>
+#include <pthread.h>
+#include <vnet/session/application_interface.h>
+#include <svm/fifo_segment.h>
+
+#define vl_typedefs		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_typedefs
+
+/* declare message handlers for each api */
+
+#define vl_endianfun		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...)
+#define vl_printfun
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_printfun
+
+typedef enum
+{
+  STATE_START,
+  STATE_ATTACHED,
+  STATE_BOUND,
+  STATE_READY,
+  STATE_FAILED,
+  STATE_DISCONNECTING,
+  STATE_DETACHED
+} connection_state_t;
+
+typedef struct
+{
+  /* vpe input queue */
+  svm_queue_t *vl_input_queue;
+
+  /* API client handle */
+  u32 my_client_index;
+
+  /* The URI we're playing with */
+  u8 *listen_uri;
+
+  /* URI for connect */
+  u8 *connect_uri;
+
+  /* Session pool */
+  app_session_t *sessions;
+
+  /* Hash table for disconnect processing */
+  uword *session_index_by_vpp_handles;
+
+  /* fifo segment */
+  fifo_segment_t *seg;
+
+  /* intermediate rx buffer */
+  u8 *rx_buf;
+
+  u32 fifo_size;
+  int i_am_server;
+  u8 is_connected;
+
+  /* Our event queue */
+  svm_msg_q_t *our_event_queue;
+  svm_msg_q_t *ct_event_queue;
+
+  /* $$$ single thread only for the moment */
+  svm_msg_q_t *vpp_event_queue;
+
+  /* $$$$ hack: cut-through session index */
+  volatile u32 cut_through_session_index;
+  volatile u32 connected_session;
+
+  /* unique segment name counter */
+  u32 unique_segment_index;
+
+  pid_t my_pid;
+
+  /* pthread handle */
+  pthread_t cut_through_thread_handle;
+
+  /* For deadman timers */
+  clib_time_t clib_time;
+
+  /* State of the connection, shared between msg RX thread and main thread */
+  volatile connection_state_t state;
+
+  volatile int time_to_stop;
+  volatile int time_to_print_stats;
+
+  u32 configured_segment_size;
+
+  /* VNET_API_ERROR_FOO -> "Foo" hash table */
+  uword *error_string_by_error_number;
+
+  fifo_segment_main_t segment_main;
+
+  u8 *connect_test_data;
+
+  uword *segments_table;
+  u8 do_echo;
+  u8 have_return;
+  u64 total_to_send;
+  u64 bytes_to_send;
+  u64 bytes_sent;
+} udp_echo_main_t;
+
+udp_echo_main_t udp_echo_main;
+
+static void
+stop_signal (int signum)
+{
+  udp_echo_main_t *um = &udp_echo_main;
+
+  um->time_to_stop = 1;
+}
+
+static void
+stats_signal (int signum)
+{
+  udp_echo_main_t *um = &udp_echo_main;
+  um->time_to_print_stats = 1;
+}
+
+static clib_error_t *
+setup_signal_handlers (void)
+{
+  signal (SIGINT, stats_signal);
+  signal (SIGQUIT, stop_signal);
+  signal (SIGTERM, stop_signal);
+
+  return 0;
+}
+
+uword
+unformat_ip4_address (unformat_input_t * input, va_list * args)
+{
+  u8 *result = va_arg (*args, u8 *);
+  unsigned a[4];
+
+  if (!unformat (input, "%d.%d.%d.%d", &a[0], &a[1], &a[2], &a[3]))
+    return 0;
+
+  if (a[0] >= 256 || a[1] >= 256 || a[2] >= 256 || a[3] >= 256)
+    return 0;
+
+  result[0] = a[0];
+  result[1] = a[1];
+  result[2] = a[2];
+  result[3] = a[3];
+
+  return 1;
+}
+
+uword
+unformat_ip6_address (unformat_input_t * input, va_list * args)
+{
+  ip6_address_t *result = va_arg (*args, ip6_address_t *);
+  u16 hex_quads[8];
+  uword hex_quad, n_hex_quads, hex_digit, n_hex_digits;
+  uword c, n_colon, double_colon_index;
+
+  n_hex_quads = hex_quad = n_hex_digits = n_colon = 0;
+  double_colon_index = ARRAY_LEN (hex_quads);
+  while ((c = unformat_get_input (input)) != UNFORMAT_END_OF_INPUT)
+    {
+      hex_digit = 16;
+      if (c >= '0' && c <= '9')
+	hex_digit = c - '0';
+      else if (c >= 'a' && c <= 'f')
+	hex_digit = c + 10 - 'a';
+      else if (c >= 'A' && c <= 'F')
+	hex_digit = c + 10 - 'A';
+      else if (c == ':' && n_colon < 2)
+	n_colon++;
+      else
+	{
+	  unformat_put_input (input);
+	  break;
+	}
+
+      /* Too many hex quads. */
+      if (n_hex_quads >= ARRAY_LEN (hex_quads))
+	return 0;
+
+      if (hex_digit < 16)
+	{
+	  hex_quad = (hex_quad << 4) | hex_digit;
+
+	  /* Hex quad must fit in 16 bits. */
+	  if (n_hex_digits >= 4)
+	    return 0;
+
+	  n_colon = 0;
+	  n_hex_digits++;
+	}
+
+      /* Save position of :: */
+      if (n_colon == 2)
+	{
+	  /* More than one :: ? */
+	  if (double_colon_index < ARRAY_LEN (hex_quads))
+	    return 0;
+	  double_colon_index = n_hex_quads;
+	}
+
+      if (n_colon > 0 && n_hex_digits > 0)
+	{
+	  hex_quads[n_hex_quads++] = hex_quad;
+	  hex_quad = 0;
+	  n_hex_digits = 0;
+	}
+    }
+
+  if (n_hex_digits > 0)
+    hex_quads[n_hex_quads++] = hex_quad;
+
+  {
+    word i;
+
+    /* Expand :: to appropriate number of zero hex quads. */
+    if (double_colon_index < ARRAY_LEN (hex_quads))
+      {
+	word n_zero = ARRAY_LEN (hex_quads) - n_hex_quads;
+
+	for (i = n_hex_quads - 1; i >= (signed) double_colon_index; i--)
+	  hex_quads[n_zero + i] = hex_quads[i];
+
+	for (i = 0; i < n_zero; i++)
+	  hex_quads[double_colon_index + i] = 0;
+
+	n_hex_quads = ARRAY_LEN (hex_quads);
+      }
+
+    /* Too few hex quads given. */
+    if (n_hex_quads < ARRAY_LEN (hex_quads))
+      return 0;
+
+    for (i = 0; i < ARRAY_LEN (hex_quads); i++)
+      result->as_u16[i] = clib_host_to_net_u16 (hex_quads[i]);
+
+    return 1;
+  }
+}
+
+uword
+unformat_uri (unformat_input_t * input, va_list * args)
+{
+  session_endpoint_cfg_t *sep = va_arg (*args, session_endpoint_cfg_t *);
+  u32 port;
+  char *tmp;
+
+  if (unformat (input, "%s://%U/%d", &tmp, unformat_ip4_address, &sep->ip.ip4,
+		&port))
+    {
+      sep->port = clib_host_to_net_u16 (port);
+      sep->is_ip4 = 1;
+      return 1;
+    }
+  else if (unformat (input, "%s://%U/%d", &tmp, unformat_ip6_address,
+		     &sep->ip.ip6, &port))
+    {
+      sep->port = clib_host_to_net_u16 (port);
+      sep->is_ip4 = 0;
+      return 1;
+    }
+  return 0;
+}
+
+static void
+application_send_attach (udp_echo_main_t * utm)
+{
+  vl_api_application_attach_t *bmp;
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_APPLICATION_ATTACH);
+  bmp->client_index = utm->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  bmp->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_ADD_SEGMENT;
+  bmp->options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_GLOBAL_SCOPE;
+  bmp->options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_LOCAL_SCOPE;
+  bmp->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] = 2;
+  bmp->options[APP_OPTIONS_RX_FIFO_SIZE] = utm->fifo_size;
+  bmp->options[APP_OPTIONS_TX_FIFO_SIZE] = utm->fifo_size;
+  bmp->options[APP_OPTIONS_ADD_SEGMENT_SIZE] = 128 << 20;
+  bmp->options[APP_OPTIONS_SEGMENT_SIZE] = 256 << 20;
+  bmp->options[APP_OPTIONS_EVT_QUEUE_SIZE] = 16768;
+  vl_msg_api_send_shmem (utm->vl_input_queue, (u8 *) & bmp);
+}
+
+void
+application_detach (udp_echo_main_t * utm)
+{
+  vl_api_application_detach_t *bmp;
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_APPLICATION_DETACH);
+  bmp->client_index = utm->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  vl_msg_api_send_shmem (utm->vl_input_queue, (u8 *) & bmp);
+}
+
+static void
+vl_api_application_attach_reply_t_handler (vl_api_application_attach_reply_t *
+					   mp)
+{
+  fifo_segment_create_args_t _a = { 0 }, *a = &_a;
+  udp_echo_main_t *utm = &udp_echo_main;
+  fifo_segment_main_t *sm = &utm->segment_main;
+  int rv;
+
+  if (mp->retval)
+    {
+      clib_warning ("attach failed: %d", mp->retval);
+      utm->state = STATE_FAILED;
+      return;
+    }
+
+  if (mp->segment_name_length == 0)
+    {
+      clib_warning ("segment_name_length zero");
+      return;
+    }
+
+  a->segment_name = (char *) mp->segment_name;
+  a->segment_size = mp->segment_size;
+
+  ASSERT (mp->app_event_queue_address);
+
+  /* Attach to the segment vpp created */
+  rv = fifo_segment_attach (sm, a);
+  if (rv)
+    {
+      clib_warning ("svm_fifo_segment_attach ('%s') failed",
+		    mp->segment_name);
+      return;
+    }
+
+  utm->our_event_queue = uword_to_pointer (mp->app_event_queue_address,
+					   svm_msg_q_t *);
+  utm->state = STATE_ATTACHED;
+}
+
+static void
+vl_api_application_detach_reply_t_handler (vl_api_application_detach_reply_t *
+					   mp)
+{
+  if (mp->retval)
+    clib_warning ("detach returned with err: %d", mp->retval);
+  udp_echo_main.state = STATE_DETACHED;
+}
+
+u8 *
+format_api_error (u8 * s, va_list * args)
+{
+  udp_echo_main_t *utm = va_arg (*args, udp_echo_main_t *);
+  i32 error = va_arg (*args, u32);
+  uword *p;
+
+  p = hash_get (utm->error_string_by_error_number, -error);
+
+  if (p)
+    s = format (s, "%s", p[0]);
+  else
+    s = format (s, "%d", error);
+  return s;
+}
+
+int
+wait_for_state_change (udp_echo_main_t * utm, connection_state_t state)
+{
+#if CLIB_DEBUG > 0
+#define TIMEOUT 600.0
+#else
+#define TIMEOUT 600.0
+#endif
+
+  f64 timeout = clib_time_now (&utm->clib_time) + TIMEOUT;
+
+  while (clib_time_now (&utm->clib_time) < timeout)
+    {
+      if (utm->state == state)
+	return 0;
+      if (utm->state == STATE_FAILED)
+	return -1;
+    }
+  return -1;
+}
+
+u64 server_bytes_received, server_bytes_sent;
+
+__clib_unused static void *
+cut_through_thread_fn (void *arg)
+{
+  app_session_t *s;
+  svm_fifo_t *rx_fifo;
+  svm_fifo_t *tx_fifo;
+  u8 *my_copy_buffer = 0;
+  udp_echo_main_t *utm = &udp_echo_main;
+  i32 actual_transfer;
+  int rv, do_dequeue = 0;
+  u32 buffer_offset;
+
+  while (utm->cut_through_session_index == ~0)
+    ;
+
+  s = pool_elt_at_index (utm->sessions, utm->cut_through_session_index);
+
+  rx_fifo = s->rx_fifo;
+  tx_fifo = s->tx_fifo;
+
+  vec_validate (my_copy_buffer, 64 * 1024 - 1);
+
+  while (1)
+    {
+      do
+	{
+	  /* We read from the tx fifo and write to the rx fifo */
+	  if (utm->have_return || do_dequeue)
+	    actual_transfer = svm_fifo_dequeue (rx_fifo,
+						vec_len (my_copy_buffer),
+						my_copy_buffer);
+	  else
+	    {
+	      /* We don't do anything with the data, drop it */
+	      actual_transfer = svm_fifo_max_dequeue_cons (rx_fifo);
+	      svm_fifo_dequeue_drop (rx_fifo, actual_transfer);
+	    }
+	}
+      while (actual_transfer <= 0);
+
+      server_bytes_received += actual_transfer;
+
+      if (utm->have_return)
+	{
+	  buffer_offset = 0;
+	  while (actual_transfer > 0)
+	    {
+	      rv = svm_fifo_enqueue (tx_fifo, actual_transfer,
+				     my_copy_buffer + buffer_offset);
+	      if (rv > 0)
+		{
+		  actual_transfer -= rv;
+		  buffer_offset += rv;
+		  server_bytes_sent += rv;
+		}
+
+	    }
+	}
+      if (PREDICT_FALSE (utm->time_to_stop))
+	break;
+    }
+
+  pthread_exit (0);
+}
+
+static void
+session_accepted_handler (session_accepted_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  udp_echo_main_t *utm = &udp_echo_main;
+  session_accepted_reply_msg_t *rmp;
+  svm_fifo_t *rx_fifo, *tx_fifo;
+  app_session_t *session;
+  static f64 start_time;
+  u32 session_index;
+  int rv = 0;
+
+  if (start_time == 0.0)
+    start_time = clib_time_now (&utm->clib_time);
+
+  utm->vpp_event_queue = uword_to_pointer (mp->vpp_event_queue_address,
+					   svm_msg_q_t *);
+  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+
+  pool_get (utm->sessions, session);
+  clib_memset (session, 0, sizeof (*session));
+  session_index = session - utm->sessions;
+  session->session_index = session_index;
+
+  rx_fifo->client_session_index = session_index;
+  tx_fifo->client_session_index = session_index;
+  session->rx_fifo = rx_fifo;
+  session->tx_fifo = tx_fifo;
+  clib_memcpy_fast (&session->transport.rmt_ip, &mp->rmt.ip,
+		    sizeof (ip46_address_t));
+  session->transport.is_ip4 = mp->rmt.is_ip4;
+  session->transport.rmt_port = mp->rmt.port;
+
+  hash_set (utm->session_index_by_vpp_handles, mp->handle, session_index);
+  if (pool_elts (utm->sessions) && (pool_elts (utm->sessions) % 20000) == 0)
+    {
+      f64 now = clib_time_now (&utm->clib_time);
+      fformat (stdout, "%d active sessions in %.2f seconds, %.2f/sec...\n",
+	       pool_elts (utm->sessions), now - start_time,
+	       (f64) pool_elts (utm->sessions) / (now - start_time));
+    }
+
+  app_alloc_ctrl_evt_to_vpp (utm->vpp_event_queue, app_evt,
+			     SESSION_CTRL_EVT_ACCEPTED_REPLY);
+  rmp = (session_accepted_reply_msg_t *) app_evt->evt->data;
+  rmp->handle = mp->handle;
+  rmp->context = mp->context;
+  rmp->retval = rv;
+  app_send_ctrl_evt_to_vpp (utm->vpp_event_queue, app_evt);
+
+  CLIB_MEMORY_BARRIER ();
+  utm->state = STATE_READY;
+}
+
+static void
+session_disconnected_handler (session_disconnected_msg_t * mp)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  udp_echo_main_t *utm = &udp_echo_main;
+  session_disconnected_reply_msg_t *rmp;
+  app_session_t *session;
+  uword *p;
+  int rv = 0;
+
+  p = hash_get (utm->session_index_by_vpp_handles, mp->handle);
+
+  if (p)
+    {
+      session = pool_elt_at_index (utm->sessions, p[0]);
+      hash_unset (utm->session_index_by_vpp_handles, mp->handle);
+      clib_warning ("disconnecting %u", session->session_index);
+      pool_put (utm->sessions, session);
+    }
+  else
+    {
+      clib_warning ("couldn't find session key %llx", mp->handle);
+      return;
+    }
+
+  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+			     SESSION_CTRL_EVT_DISCONNECTED_REPLY);
+  rmp = (session_disconnected_reply_msg_t *) app_evt->evt->data;
+  rmp->retval = rv;
+  rmp->handle = mp->handle;
+  rmp->context = mp->context;
+  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+}
+
+static void
+session_connected_handler (session_connected_msg_t * mp)
+{
+  udp_echo_main_t *utm = &udp_echo_main;
+  unformat_input_t _input, *input = &_input;
+  session_endpoint_cfg_t _sep, *sep = &_sep;
+  app_session_t *session;
+
+  ASSERT (utm->i_am_server == 0);
+
+  if (mp->retval)
+    {
+      clib_warning ("failed connect");
+      return;
+    }
+
+  ASSERT (mp->server_rx_fifo && mp->server_tx_fifo);
+
+  pool_get (utm->sessions, session);
+  session->session_index = session - utm->sessions;
+  session->rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  session->tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+
+  /* Cut-through case */
+  if (mp->ct_rx_fifo)
+    {
+      clib_warning ("cut-through session");
+      session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					     svm_msg_q_t *);
+      utm->cut_through_session_index = session->session_index;
+      session->is_dgram = 0;
+      sleep (1);
+      session->rx_fifo->client_session_index = session->session_index;
+      session->tx_fifo->client_session_index = session->session_index;
+      /* TODO use ct fifos */
+    }
+  else
+    {
+      utm->connected_session = session->session_index;
+      utm->vpp_event_queue = uword_to_pointer (mp->vpp_event_queue_address,
+					       svm_msg_q_t *);
+
+      session->rx_fifo->client_session_index = session->session_index;
+      session->tx_fifo->client_session_index = session->session_index;
+      clib_memcpy_fast (&session->transport.lcl_ip, &mp->lcl.ip,
+			sizeof (ip46_address_t));
+      session->transport.is_ip4 = mp->lcl.is_ip4;
+      session->transport.lcl_port = mp->lcl.port;
+
+      unformat_init_vector (input, utm->connect_uri);
+      if (!unformat (input, "%U", unformat_uri, sep))
+	{
+	  clib_warning ("can't figure out remote ip and port");
+	  utm->state = STATE_FAILED;
+	  unformat_free (input);
+	  return;
+	}
+      unformat_free (input);
+      clib_memcpy_fast (&session->transport.rmt_ip, &sep->ip,
+			sizeof (ip46_address_t));
+      session->transport.rmt_port = sep->port;
+      session->is_dgram = !utm->is_connected;
+    }
+  utm->state = STATE_READY;
+}
+
+static void
+session_bound_handler (session_bound_msg_t * mp)
+{
+  udp_echo_main_t *utm = &udp_echo_main;
+  svm_fifo_t *rx_fifo, *tx_fifo;
+  app_session_t *session;
+  u32 session_index;
+
+  if (mp->retval)
+    {
+      clib_warning ("bind failed: %d", mp->retval);
+      utm->state = STATE_FAILED;
+      return;
+    }
+
+  rx_fifo = uword_to_pointer (mp->rx_fifo, svm_fifo_t *);
+  tx_fifo = uword_to_pointer (mp->tx_fifo, svm_fifo_t *);
+
+  pool_get (utm->sessions, session);
+  clib_memset (session, 0, sizeof (*session));
+  session_index = session - utm->sessions;
+
+  rx_fifo->client_session_index = session_index;
+  tx_fifo->client_session_index = session_index;
+  session->rx_fifo = rx_fifo;
+  session->tx_fifo = tx_fifo;
+  clib_memcpy_fast (&session->transport.lcl_ip, mp->lcl_ip,
+		    sizeof (ip46_address_t));
+  session->transport.is_ip4 = mp->lcl_is_ip4;
+  session->transport.lcl_port = mp->lcl_port;
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_evt_q, svm_msg_q_t *);
+
+  utm->state = utm->is_connected ? STATE_BOUND : STATE_READY;
+}
+
+static void
+handle_mq_event (session_event_t * e)
+{
+  switch (e->event_type)
+    {
+    case SESSION_CTRL_EVT_BOUND:
+      session_bound_handler ((session_bound_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_ACCEPTED:
+      session_accepted_handler ((session_accepted_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_CONNECTED:
+      session_connected_handler ((session_connected_msg_t *) e->data);
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED:
+      session_disconnected_handler ((session_disconnected_msg_t *) e->data);
+      break;
+    default:
+      clib_warning ("unhandled %u", e->event_type);
+    }
+}
+
+static void
+udp_client_send_connect (udp_echo_main_t * utm)
+{
+  vl_api_connect_uri_t *cmp;
+  cmp = vl_msg_api_alloc (sizeof (*cmp));
+  clib_memset (cmp, 0, sizeof (*cmp));
+
+  cmp->_vl_msg_id = ntohs (VL_API_CONNECT_URI);
+  cmp->client_index = utm->my_client_index;
+  cmp->context = ntohl (0xfeedface);
+  memcpy (cmp->uri, utm->connect_uri, vec_len (utm->connect_uri));
+  vl_msg_api_send_shmem (utm->vl_input_queue, (u8 *) & cmp);
+}
+
+static void
+send_test_chunk (udp_echo_main_t * utm, app_session_t * s, u32 bytes)
+{
+  u64 test_buf_len, bytes_this_chunk, test_buf_offset;
+
+  u8 *test_data = utm->connect_test_data;
+  u32 enq_space;
+  int written;
+
+  test_buf_len = vec_len (test_data);
+  test_buf_offset = utm->bytes_sent % test_buf_len;
+  bytes_this_chunk = clib_min (test_buf_len - test_buf_offset,
+			       utm->bytes_to_send);
+  enq_space = svm_fifo_max_enqueue_prod (s->tx_fifo);
+  bytes_this_chunk = clib_min (bytes_this_chunk, enq_space);
+
+  written = app_send (s, test_data + test_buf_offset, bytes_this_chunk,
+		      SVM_Q_WAIT);
+  if (written > 0)
+    {
+      utm->bytes_to_send -= written;
+      utm->bytes_sent += written;
+    }
+}
+
+static void
+recv_test_chunk (udp_echo_main_t * utm, app_session_t * s)
+{
+  app_recv (s, utm->rx_buf, vec_len (utm->rx_buf));
+}
+
+void
+client_send_data (udp_echo_main_t * utm, u32 session_index)
+{
+  f64 start_time, end_time, delta;
+  app_session_t *session;
+  char *transfer_type;
+  u8 *test_data;
+  int i;
+
+  vec_validate_aligned (utm->connect_test_data, 1024 * 1024 - 1,
+			CLIB_CACHE_LINE_BYTES);
+  for (i = 0; i < vec_len (utm->connect_test_data); i++)
+    utm->connect_test_data[i] = i & 0xff;
+
+  test_data = utm->connect_test_data;
+  session = pool_elt_at_index (utm->sessions, session_index);
+  ASSERT (vec_len (test_data) > 0);
+
+  utm->total_to_send = utm->bytes_to_send;
+  vec_validate (utm->rx_buf, vec_len (test_data) - 1);
+  start_time = clib_time_now (&utm->clib_time);
+  while (!utm->time_to_stop && utm->bytes_to_send)
+    {
+      send_test_chunk (utm, session, 0);
+      if (utm->have_return)
+	recv_test_chunk (utm, session);
+      if (utm->time_to_stop)
+	break;
+    }
+
+  if (utm->have_return)
+    {
+      f64 timeout = clib_time_now (&utm->clib_time) + 5;
+      while (clib_time_now (&utm->clib_time) < timeout)
+	recv_test_chunk (utm, session);
+    }
+
+  end_time = clib_time_now (&utm->clib_time);
+  delta = end_time - start_time;
+  transfer_type = utm->have_return ? "full-duplex" : "half-duplex";
+  clib_warning ("%lld bytes (%lld mbytes, %lld gbytes) in %.2f seconds",
+		utm->total_to_send, utm->total_to_send / (1ULL << 20),
+		utm->total_to_send / (1ULL << 30), delta);
+  clib_warning ("%.2f bytes/second %s", ((f64) utm->total_to_send) / (delta),
+		transfer_type);
+  clib_warning ("%.4f gbit/second %s",
+		(((f64) utm->total_to_send * 8.0) / delta / 1e9),
+		transfer_type);
+}
+
+static int
+application_attach (udp_echo_main_t * utm)
+{
+  application_send_attach (utm);
+  if (wait_for_state_change (utm, STATE_ATTACHED))
+    {
+      clib_warning ("timeout waiting for STATE_ATTACHED");
+      return -1;
+    }
+  return 0;
+}
+
+static void
+client_test (udp_echo_main_t * utm)
+{
+  f64 start_time, timeout = 100.0;
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+
+  if (application_attach (utm))
+    return;
+
+  udp_client_send_connect (utm);
+
+  start_time = clib_time_now (&utm->clib_time);
+  while (pool_elts (utm->sessions) != 1 && utm->state != STATE_FAILED)
+    {
+      svm_msg_q_sub (utm->our_event_queue, &msg, SVM_Q_WAIT, 0);
+      e = svm_msg_q_msg_data (utm->our_event_queue, &msg);
+      handle_mq_event (e);
+      svm_msg_q_free_msg (utm->our_event_queue, &msg);
+
+      if (clib_time_now (&utm->clib_time) - start_time >= timeout)
+	break;
+    }
+
+  if (utm->cut_through_session_index != ~0)
+    client_send_data (utm, utm->cut_through_session_index);
+  else
+    client_send_data (utm, utm->connected_session);
+
+  application_detach (utm);
+  wait_for_state_change (utm, STATE_DETACHED);
+}
+
+static void
+vl_api_map_another_segment_t_handler (vl_api_map_another_segment_t * mp)
+{
+  fifo_segment_create_args_t _a, *a = &_a;
+  udp_echo_main_t *utm = &udp_echo_main;
+  fifo_segment_main_t *sm = &utm->segment_main;
+  fifo_segment_t *seg;
+  int rv;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->segment_name = (char *) mp->segment_name;
+  a->segment_size = mp->segment_size;
+  /* Attach to the segment vpp created */
+  rv = fifo_segment_attach (sm, a);
+  if (rv)
+    {
+      clib_warning ("svm_fifo_segment_attach ('%s') failed",
+		    mp->segment_name);
+      return;
+    }
+  seg = fifo_segment_get_segment (sm, a->new_segment_indices[0]);
+  clib_warning ("Mapped new segment '%s' size %d", seg->ssvm.name,
+		seg->ssvm.ssvm_size);
+  hash_set (utm->segments_table, clib_net_to_host_u64 (mp->segment_handle),
+	    a->new_segment_indices[0]);
+}
+
+static void
+vl_api_unmap_segment_t_handler (vl_api_unmap_segment_t * mp)
+{
+  udp_echo_main_t *utm = &udp_echo_main;
+  fifo_segment_main_t *sm = &utm->segment_main;
+  fifo_segment_t *seg;
+  uword *seg_indexp;
+  u64 segment_handle;
+
+  segment_handle = clib_net_to_host_u64 (mp->segment_handle);
+  seg_indexp = hash_get (utm->segments_table, segment_handle);
+  if (!seg_indexp)
+    {
+      clib_warning ("segment not mapped: %s", segment_handle);
+      return;
+    }
+  hash_unset (utm->segments_table, segment_handle);
+  seg = fifo_segment_get_segment (sm, (u32) seg_indexp[0]);
+  fifo_segment_delete (sm, seg);
+  clib_warning ("Unmapped segment '%s'", segment_handle);
+}
+
+static void
+vl_api_unbind_uri_reply_t_handler (vl_api_unbind_uri_reply_t * mp)
+{
+  udp_echo_main_t *utm = &udp_echo_main;
+
+  if (mp->retval != 0)
+    clib_warning ("returned %d", ntohl (mp->retval));
+
+  utm->state = STATE_START;
+}
+
+static void
+  vl_api_app_cut_through_registration_add_t_handler
+  (vl_api_app_cut_through_registration_add_t * mp)
+{
+
+}
+
+#define foreach_tcp_echo_msg                         			\
+_(UNBIND_URI_REPLY, unbind_uri_reply)           			\
+_(MAP_ANOTHER_SEGMENT, map_another_segment)				\
+_(UNMAP_SEGMENT, unmap_segment)						\
+_(APPLICATION_ATTACH_REPLY, application_attach_reply)			\
+_(APPLICATION_DETACH_REPLY, application_detach_reply)			\
+_(APP_CUT_THROUGH_REGISTRATION_ADD, app_cut_through_registration_add)	\
+
+void
+tcp_echo_api_hookup (udp_echo_main_t * utm)
+{
+#define _(N,n)                                                  \
+    vl_msg_api_set_handlers(VL_API_##N, #n,                     \
+                           vl_api_##n##_t_handler,              \
+                           vl_noop_handler,                     \
+                           vl_api_##n##_t_endian,               \
+                           vl_api_##n##_t_print,                \
+                           sizeof(vl_api_##n##_t), 1);
+  foreach_tcp_echo_msg;
+#undef _
+
+}
+
+int
+connect_to_vpp (char *name)
+{
+  udp_echo_main_t *utm = &udp_echo_main;
+  api_main_t *am = &api_main;
+
+  if (vl_client_connect_to_vlib ("/vpe-api", name, 32) < 0)
+    return -1;
+
+  utm->vl_input_queue = am->shmem_hdr->vl_input_queue;
+  utm->my_client_index = am->my_client_index;
+
+  return 0;
+}
+
+void
+vlib_cli_output (struct vlib_main_t *vm, char *fmt, ...)
+{
+  clib_warning ("BUG");
+}
+
+static void
+init_error_string_table (udp_echo_main_t * utm)
+{
+  utm->error_string_by_error_number = hash_create (0, sizeof (uword));
+
+#define _(n,v,s) hash_set (utm->error_string_by_error_number, -v, s);
+  foreach_vnet_api_error;
+#undef _
+
+  hash_set (utm->error_string_by_error_number, 99, "Misc");
+}
+
+void
+server_handle_fifo_event_rx (udp_echo_main_t * utm, u32 session_index)
+{
+  svm_fifo_t *rx_fifo, *tx_fifo;
+  int n_read;
+  app_session_t *session;
+  int rv;
+  u32 max_dequeue, offset, max_transfer, rx_buf_len;
+
+  session = pool_elt_at_index (utm->sessions, session_index);
+  rx_buf_len = vec_len (utm->rx_buf);
+  rx_fifo = session->rx_fifo;
+  tx_fifo = session->tx_fifo;
+
+
+  max_dequeue = svm_fifo_max_dequeue_cons (rx_fifo);
+  /* Allow enqueuing of a new event */
+  svm_fifo_unset_event (rx_fifo);
+
+  if (PREDICT_FALSE (!max_dequeue))
+    return;
+
+  /* Read the max_dequeue */
+  do
+    {
+      max_transfer = clib_min (rx_buf_len, max_dequeue);
+      if (session->is_dgram)
+	n_read = app_recv_dgram_raw (rx_fifo, utm->rx_buf, max_transfer,
+				     &session->transport, 0, 0);
+      else
+	n_read = app_recv_stream_raw (rx_fifo, utm->rx_buf, max_transfer, 0,
+				      0);
+
+      if (n_read > 0)
+	max_dequeue -= n_read;
+
+      /* Reflect if a non-drop session */
+      if (utm->have_return && n_read > 0)
+	{
+	  offset = 0;
+	  do
+	    {
+	      rv = app_send (session, &utm->rx_buf[offset], n_read,
+			     SVM_Q_WAIT);
+	      if (rv > 0)
+		{
+		  n_read -= rv;
+		  offset += rv;
+		}
+	    }
+	  while ((rv <= 0 || n_read > 0) && !utm->time_to_stop);
+
+	  /* If event wasn't set, add one */
+	  if (svm_fifo_set_event (tx_fifo))
+	    app_send_io_evt_to_vpp (session->vpp_evt_q,
+				    tx_fifo->master_session_index,
+				    SESSION_IO_EVT_TX, SVM_Q_WAIT);
+	}
+    }
+  while ((n_read < 0 || max_dequeue > 0) && !utm->time_to_stop);
+}
+
+static void
+server_handle_event_queue (udp_echo_main_t * utm)
+{
+  session_event_t *e;
+  svm_msg_q_msg_t msg;
+  svm_msg_q_t *mq = utm->our_event_queue;
+
+  while (utm->state != STATE_READY)
+    sleep (5);
+
+  while (1)
+    {
+      if (svm_msg_q_sub (mq, &msg, SVM_Q_WAIT, 0))
+	{
+	  clib_warning ("svm msg q returned");
+	  continue;
+	}
+      e = svm_msg_q_msg_data (mq, &msg);
+      switch (e->event_type)
+	{
+	case SESSION_IO_EVT_RX:
+	  server_handle_fifo_event_rx (utm, e->session_index);
+	  break;
+
+	default:
+	  handle_mq_event (e);
+	  break;
+	}
+      svm_msg_q_free_msg (mq, &msg);
+      if (PREDICT_FALSE (utm->time_to_stop == 1))
+	return;
+      if (PREDICT_FALSE (utm->time_to_print_stats == 1))
+	{
+	  utm->time_to_print_stats = 0;
+	  fformat (stdout, "%d connections\n", pool_elts (utm->sessions));
+	}
+    }
+}
+
+static void
+server_unbind (udp_echo_main_t * utm)
+{
+  vl_api_unbind_uri_t *ump;
+
+  ump = vl_msg_api_alloc (sizeof (*ump));
+  clib_memset (ump, 0, sizeof (*ump));
+
+  ump->_vl_msg_id = ntohs (VL_API_UNBIND_URI);
+  ump->client_index = utm->my_client_index;
+  memcpy (ump->uri, utm->listen_uri, vec_len (utm->listen_uri));
+  vl_msg_api_send_shmem (utm->vl_input_queue, (u8 *) & ump);
+}
+
+static void
+server_bind (udp_echo_main_t * utm)
+{
+  vl_api_bind_uri_t *bmp;
+
+  bmp = vl_msg_api_alloc (sizeof (*bmp));
+  clib_memset (bmp, 0, sizeof (*bmp));
+
+  bmp->_vl_msg_id = ntohs (VL_API_BIND_URI);
+  bmp->client_index = utm->my_client_index;
+  bmp->context = ntohl (0xfeedface);
+  memcpy (bmp->uri, utm->listen_uri, vec_len (utm->listen_uri));
+  vl_msg_api_send_shmem (utm->vl_input_queue, (u8 *) & bmp);
+}
+
+void
+udp_server_test (udp_echo_main_t * utm)
+{
+  u8 wait_for_state = utm->is_connected ? STATE_BOUND : STATE_READY;
+  application_send_attach (utm);
+
+  /* Bind to uri */
+  server_bind (utm);
+
+  if (wait_for_state_change (utm, wait_for_state))
+    {
+      clib_warning ("timeout waiting for state change");
+      return;
+    }
+
+  server_handle_event_queue (utm);
+
+  /* Cleanup */
+  server_unbind (utm);
+
+  if (wait_for_state_change (utm, STATE_START))
+    {
+      clib_warning ("timeout waiting for STATE_START");
+      return;
+    }
+
+  application_detach (utm);
+
+  fformat (stdout, "Test complete...\n");
+}
+
+int
+main (int argc, char **argv)
+{
+  udp_echo_main_t *utm = &udp_echo_main;
+  fifo_segment_main_t *sm = &utm->segment_main;
+  u8 *uri = (u8 *) "udp://6.0.1.1/1234";
+  unformat_input_t _argv, *a = &_argv;
+  int i_am_server = 1;
+  app_session_t *session;
+  u8 *chroot_prefix;
+  char *app_name;
+  u32 tmp;
+  int i;
+
+  clib_mem_init_thread_safe (0, 256 << 20);
+
+  fifo_segment_main_init (sm, HIGH_SEGMENT_BASEVA, 20);
+
+  vec_validate (utm->rx_buf, 128 << 10);
+  utm->session_index_by_vpp_handles = hash_create (0, sizeof (uword));
+  utm->my_pid = getpid ();
+  utm->configured_segment_size = 1 << 20;
+  utm->have_return = 1;
+  utm->bytes_to_send = 1024;
+  utm->fifo_size = 128 << 10;
+  utm->cut_through_session_index = ~0;
+  clib_time_init (&utm->clib_time);
+
+  init_error_string_table (utm);
+  unformat_init_command_line (a, argv);
+
+  while (unformat_check_input (a) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (a, "chroot prefix %s", &chroot_prefix))
+	{
+	  vl_set_memory_root_path ((char *) chroot_prefix);
+	}
+      else if (unformat (a, "uri %s", &uri))
+	;
+      else if (unformat (a, "segment-size %dM", &tmp))
+	utm->configured_segment_size = tmp << 20;
+      else if (unformat (a, "segment-size %dG", &tmp))
+	utm->configured_segment_size = tmp << 30;
+      else if (unformat (a, "server"))
+	i_am_server = 1;
+      else if (unformat (a, "client"))
+	i_am_server = 0;
+      else if (unformat (a, "no-return"))
+	utm->have_return = 0;
+      else if (unformat (a, "mbytes %d", &tmp))
+	utm->bytes_to_send = (u64) tmp << 20;
+      else if (unformat (a, "fifo-size %d", &tmp))
+	utm->fifo_size = tmp << 10;
+      else
+	{
+	  fformat (stderr, "%s: usage [server|client]\n");
+	  exit (1);
+	}
+    }
+
+  utm->i_am_server = i_am_server;
+
+  setup_signal_handlers ();
+  tcp_echo_api_hookup (utm);
+
+  if (i_am_server)
+    {
+      utm->listen_uri = format (0, "%s%c", uri, 0);
+      utm->is_connected = (utm->listen_uri[4] == 'c');
+      app_name = "udp_echo_server";
+    }
+  else
+    {
+      app_name = "udp_echo_client";
+      utm->connect_uri = format (0, "%s%c", uri, 0);
+      utm->is_connected = (utm->connect_uri[4] == 'c');
+    }
+  if (connect_to_vpp (app_name) < 0)
+    {
+      svm_region_exit ();
+      fformat (stderr, "Couldn't connect to vpe, exiting...\n");
+      exit (1);
+    }
+
+  if (i_am_server == 0)
+    {
+      client_test (utm);
+      goto done;
+    }
+
+  /* $$$$ hack preallocation */
+  for (i = 0; i < 200000; i++)
+    {
+      pool_get (utm->sessions, session);
+      clib_memset (session, 0, sizeof (*session));
+    }
+  for (i = 0; i < 200000; i++)
+    pool_put_index (utm->sessions, i);
+
+  udp_server_test (utm);
+
+done:
+  vl_client_disconnect_from_vlib ();
+  exit (0);
+}
+
+#undef vl_api_version
+#define vl_api_version(n,v) static u32 vpe_api_version = v;
+#include <vpp/api/vpe.api.h>
+#undef vl_api_version
+
+void
+vl_client_add_api_signatures (vl_api_memclnt_create_t * mp)
+{
+  /*
+   * Send the main API signature in slot 0. This bit of code must
+   * match the checks in ../vpe/api/api.c: vl_msg_api_version_check().
+   */
+  mp->api_versions[0] = clib_host_to_net_u32 (vpe_api_version);
+}
+
+u32
+vl (void *p)
+{
+  return vec_len (p);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */