TCP proxy prototype

- Clean up internal API client registration
- Add proxy server
- Add a reference count to the svm fifo

Change-Id: I5ace1c85497062ed412d26ae76a9e6741af1e984
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Florin Coras <fcoras@cisco.com>

16 files changed, 801 insertions, 212 deletions

diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index fc2189c5176..e478c06e891 100644
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -201,14 +201,20 @@ svm_fifo_create (u32 data_size_in_bytes)
   memset (f, 0, sizeof (*f));
   f->nitems = data_size_in_bytes;
   f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
+  f->refcnt = 1;
   return (f);
 }
 
 void
 svm_fifo_free (svm_fifo_t * f)
 {
-  pool_free (f->ooo_segments);
-  clib_mem_free (f);
+  ASSERT (f->refcnt > 0);
+
+  if (--f->refcnt == 0)
+    {
+      pool_free (f->ooo_segments);
+      clib_mem_free (f);
+    }
 }
 
 always_inline ooo_segment_t *
diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h
index a83cd858f83..f10b4d91a2a 100644
--- a/src/svm/svm_fifo.h
+++ b/src/svm/svm_fifo.h
@@ -75,6 +75,7 @@ typedef struct _svm_fifo
 #if SVM_FIFO_TRACE
   svm_fifo_trace_elem_t *trace;
 #endif
+  i8 refcnt;
     CLIB_CACHE_LINE_ALIGN_MARK (data);
 } svm_fifo_t;
 
diff --git a/src/svm/svm_fifo_segment.c b/src/svm/svm_fifo_segment.c
index 86661e516a2..c04b9d8ccba 100644
--- a/src/svm/svm_fifo_segment.c
+++ b/src/svm/svm_fifo_segment.c
@@ -296,6 +296,7 @@ svm_fifo_segment_alloc_fifo (svm_fifo_segment_private_t * s,
 	  memset (f, 0, sizeof (*f));
 	  f->nitems = data_size_in_bytes;
 	  f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
+	  f->refcnt = 1;
 	  goto found;
 	}
       /* FALLTHROUGH */
@@ -344,6 +345,10 @@ svm_fifo_segment_free_fifo (svm_fifo_segment_private_t * s, svm_fifo_t * f,
   svm_fifo_segment_header_t *fsh;
   void *oldheap;
 
+  ASSERT (f->refcnt > 0);
+
+  if (--f->refcnt > 0)
+    return;
 
   sh = s->ssvm.sh;
   fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
diff --git a/src/vlibmemory/api_common.h b/src/vlibmemory/api_common.h
index 53909cc4184..19daecdfb6a 100644
--- a/src/vlibmemory/api_common.h
+++ b/src/vlibmemory/api_common.h
@@ -126,6 +126,7 @@ int vl_client_connect_to_vlib_no_rx_pthread (const char *svm_name,
 u16 vl_client_get_first_plugin_msg_id (const char *plugin_name);
 
 void vl_api_rpc_call_main_thread (void *fp, u8 * data, u32 data_length);
+u32 vl_api_memclnt_create_internal (char *, unix_shared_memory_queue_t *);
 
 #endif /* included_vlibmemory_api_common_h */
 
diff --git a/src/vlibmemory/memory_vlib.c b/src/vlibmemory/memory_vlib.c
index 004a997455e..688ce6044e0 100644
--- a/src/vlibmemory/memory_vlib.c
+++ b/src/vlibmemory/memory_vlib.c
@@ -137,6 +137,44 @@ vl_api_serialize_message_table (api_main_t * am, u8 * vector)
 }
 
 /*
+ * vl_api_memclnt_create_internal
+ */
+
+u32
+vl_api_memclnt_create_internal (char *name, unix_shared_memory_queue_t * q)
+{
+  vl_api_registration_t **regpp;
+  vl_api_registration_t *regp;
+  svm_region_t *svm;
+  void *oldheap;
+  api_main_t *am = &api_main;
+
+  ASSERT (vlib_get_thread_index () == 0);
+  pool_get (am->vl_clients, regpp);
+
+  svm = am->vlib_rp;
+
+  pthread_mutex_lock (&svm->mutex);
+  oldheap = svm_push_data_heap (svm);
+  *regpp = clib_mem_alloc (sizeof (vl_api_registration_t));
+
+  regp = *regpp;
+  memset (regp, 0, sizeof (*regp));
+  regp->registration_type = REGISTRATION_TYPE_SHMEM;
+  regp->vl_api_registration_pool_index = regpp - am->vl_clients;
+
+  regp->vl_input_queue = q;
+  regp->name = format (0, "%s%c", name, 0);
+
+  pthread_mutex_unlock (&svm->mutex);
+  svm_pop_heap (oldheap);
+  return vl_msg_api_handle_from_index_and_epoch
+    (regp->vl_api_registration_pool_index,
+     am->shmem_hdr->application_restarts);
+}
+
+
+/*
  * vl_api_memclnt_create_t_handler
  */
 void
diff --git a/src/vnet.am b/src/vnet.am
index ad84c028830..ede0376de1e 100644
--- a/src/vnet.am
+++ b/src/vnet.am
@@ -475,6 +475,7 @@ libvnet_la_SOURCES +=				\
  vnet/tcp/builtin_client.c			\
  vnet/tcp/builtin_server.c			\
  vnet/tcp/builtin_http_server.c			\
+ vnet/tcp/builtin_proxy.c			\
  vnet/tcp/tcp_test.c				\
  vnet/tcp/tcp.c
 
diff --git a/src/vnet/session/application.c b/src/vnet/session/application.c
index 076c66f1fff..78c41b938cf 100644
--- a/src/vnet/session/application.c
+++ b/src/vnet/session/application.c
@@ -367,6 +367,12 @@ app_get_name_from_reg_index (application_t * app)
   return app_name;
 }
 
+int
+application_is_proxy (application_t * app)
+{
+  return !(app->flags & APP_OPTIONS_FLAGS_IS_PROXY);
+}
+
 u8 *
 format_application_listener (u8 * s, va_list * args)
 {
diff --git a/src/vnet/session/application.h b/src/vnet/session/application.h
index 35caae85dbb..29d37a06b18 100644
--- a/src/vnet/session/application.h
+++ b/src/vnet/session/application.h
@@ -116,6 +116,7 @@ segment_manager_t *application_get_listen_segment_manager (application_t *
 							   s);
 segment_manager_t *application_get_connect_segment_manager (application_t *
 							    app);
+int application_is_proxy (application_t * app);
 
 #endif /* SRC_VNET_SESSION_APPLICATION_H_ */
 
diff --git a/src/vnet/session/application_interface.h b/src/vnet/session/application_interface.h
index ed9f89b361e..1d63f6cc102 100644
--- a/src/vnet/session/application_interface.h
+++ b/src/vnet/session/application_interface.h
@@ -100,6 +100,9 @@ typedef struct _vnet_connect_args
 
   /* Used for redirects */
   void *mp;
+
+  /* used for proxy connections */
+  u64 server_handle;
 } vnet_connect_args_t;
 
 typedef struct _vnet_disconnect_args_t
@@ -129,6 +132,7 @@ typedef enum
   _(USE_FIFO, "Use FIFO with redirects")			\
   _(ADD_SEGMENT, "Add segment and signal app if needed")	\
   _(BUILTIN_APP, "Application is builtin")			\
+  _(IS_PROXY, "Application is proxying")
 
 typedef enum _app_options
 {
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index 4ba152917ac..991bcd5a53f 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -30,7 +30,7 @@ extern transport_proto_vft_t *tp_vfts;
 
 int
 stream_session_create_i (segment_manager_t * sm, transport_connection_t * tc,
-			 stream_session_t ** ret_s)
+			 u8 alloc_fifos, stream_session_t ** ret_s)
 {
   session_manager_main_t *smm = &session_manager_main;
   svm_fifo_t *server_rx_fifo = 0, *server_tx_fifo = 0;
@@ -43,31 +43,37 @@ stream_session_create_i (segment_manager_t * sm, transport_connection_t * tc,
 
   ASSERT (thread_index == vlib_get_thread_index ());
 
-  if ((rv = segment_manager_alloc_session_fifos (sm, &server_rx_fifo,
-						 &server_tx_fifo,
-						 &fifo_segment_index)))
-    return rv;
-
   /* Create the session */
   pool_get_aligned (smm->sessions[thread_index], s, CLIB_CACHE_LINE_BYTES);
   memset (s, 0, sizeof (*s));
-
-  /* Initialize backpointers */
   pool_index = s - smm->sessions[thread_index];
-  server_rx_fifo->master_session_index = pool_index;
-  server_rx_fifo->master_thread_index = thread_index;
 
-  server_tx_fifo->master_session_index = pool_index;
-  server_tx_fifo->master_thread_index = thread_index;
+  /* Allocate fifos */
+  if (alloc_fifos)
+    {
+      if ((rv = segment_manager_alloc_session_fifos (sm, &server_rx_fifo,
+						     &server_tx_fifo,
+						     &fifo_segment_index)))
+	{
+	  pool_put (smm->sessions[thread_index], s);
+	  return rv;
+	}
+      /* Initialize backpointers */
+      server_rx_fifo->master_session_index = pool_index;
+      server_rx_fifo->master_thread_index = thread_index;
+
+      server_tx_fifo->master_session_index = pool_index;
+      server_tx_fifo->master_thread_index = thread_index;
 
-  s->server_rx_fifo = server_rx_fifo;
-  s->server_tx_fifo = server_tx_fifo;
+      s->server_rx_fifo = server_rx_fifo;
+      s->server_tx_fifo = server_tx_fifo;
+      s->svm_segment_index = fifo_segment_index;
+    }
 
   /* Initialize state machine, such as it is... */
   s->session_type = session_type_from_proto_and_ip (tc->transport_proto,
 						    tc->is_ip4);
   s->session_state = SESSION_STATE_CONNECTING;
-  s->svm_segment_index = fifo_segment_index;
   s->thread_index = thread_index;
   s->session_index = pool_index;
 
@@ -379,10 +385,11 @@ stream_session_connect_notify (transport_connection_t * tc, u8 is_fail)
   if (!is_fail)
     {
       segment_manager_t *sm;
+      u8 alloc_fifos;
       sm = application_get_connect_segment_manager (app);
-
+      alloc_fifos = application_is_proxy (app);
       /* Create new session (svm segments are allocated if needed) */
-      if (stream_session_create_i (sm, tc, &new_s))
+      if (stream_session_create_i (sm, tc, alloc_fifos, &new_s))
 	{
 	  is_fail = 1;
 	  error = -1;
@@ -515,7 +522,7 @@ stream_session_accept (transport_connection_t * tc, u32 listener_index,
   server = application_get (listener->app_index);
 
   sm = application_get_listen_segment_manager (server, listener);
-  if ((rv = stream_session_create_i (sm, tc, &s)))
+  if ((rv = stream_session_create_i (sm, tc, 1, &s)))
     return rv;
 
   s->app_index = server->index;
diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h
index 538433da0f2..74d82a408dc 100644
--- a/src/vnet/session/session.h
+++ b/src/vnet/session/session.h
@@ -183,10 +183,10 @@ stream_session_is_valid (u32 si, u8 thread_index)
   stream_session_t *s;
   s = pool_elt_at_index (session_manager_main.sessions[thread_index], si);
   if (s->thread_index != thread_index || s->session_index != si
-      || s->server_rx_fifo->master_session_index != si
-      || s->server_tx_fifo->master_session_index != si
-      || s->server_rx_fifo->master_thread_index != thread_index
-      || s->server_tx_fifo->master_thread_index != thread_index)
+      /* || s->server_rx_fifo->master_session_index != si
+         || s->server_tx_fifo->master_session_index != si
+         || s->server_rx_fifo->master_thread_index != thread_index
+         || s->server_tx_fifo->master_thread_index != thread_index */ )
     return 0;
   return 1;
 }
diff --git a/src/vnet/session/stream_session.h b/src/vnet/session/stream_session.h
index 82bbf521ce9..4c26321194d 100644
--- a/src/vnet/session/stream_session.h
+++ b/src/vnet/session/stream_session.h
@@ -83,8 +83,11 @@ typedef struct _stream_session_t
 
   u32 opaque2;
 
+  /** connected (server) session handle */
+  u64 server_session_handle;
+
   /** Opaque, pad to a 64-octet boundary */
-  u64 opaque[2];
+  u64 opaque[1];
 } stream_session_t;
 
 #endif /* SRC_VNET_SESSION_STREAM_SESSION_H_ */
diff --git a/src/vnet/tcp/builtin_client.c b/src/vnet/tcp/builtin_client.c
index 0cb9faa8769..938e07ba505 100644
--- a/src/vnet/tcp/builtin_client.c
+++ b/src/vnet/tcp/builtin_client.c
@@ -24,25 +24,6 @@
 #include <vlibsocket/api.h>
 #include <vpp/app/version.h>
 
-/* define message IDs */
-#include <vpp/api/vpe_msg_enum.h>
-
-/* define message structures */
-#define vl_typedefs
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_typedefs
-
-/* define generated endian-swappers */
-#define vl_endianfun
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_endianfun
-
-/* instantiate all the print functions we know about */
-#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
-#define vl_printfun
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_printfun
-
 #define TCP_BUILTIN_CLIENT_DBG (0)
 
 static void
@@ -308,87 +289,16 @@ VLIB_REGISTER_NODE (builtin_client_node) =
 };
 /* *INDENT-ON* */
 
-/* So we don't get "no handler for... " msgs */
-static void
-vl_api_memclnt_create_reply_t_handler (vl_api_memclnt_create_reply_t * mp)
-{
-  vlib_main_t *vm = vlib_get_main ();
-  tclient_main_t *tm = &tclient_main;
-  tm->my_client_index = mp->index;
-  vlib_process_signal_event (vm, tm->cli_node_index, 1 /* evt */ ,
-			     0 /* data */ );
-}
-
 static int
 create_api_loopback (tclient_main_t * tm)
 {
-  vlib_main_t *vm = vlib_get_main ();
-  vl_api_memclnt_create_t _m, *mp = &_m;
-  extern void vl_api_memclnt_create_t_handler (vl_api_memclnt_create_t *);
   api_main_t *am = &api_main;
   vl_shmem_hdr_t *shmem_hdr;
-  uword *event_data = 0, event_type;
-  int resolved = 0;
-
-  /*
-   * Create a "loopback" API client connection
-   * Don't do things like this unless you know what you're doing...
-   */
 
   shmem_hdr = am->shmem_hdr;
   tm->vl_input_queue = shmem_hdr->vl_input_queue;
-  memset (mp, 0, sizeof (*mp));
-  mp->_vl_msg_id = VL_API_MEMCLNT_CREATE;
-  mp->context = 0xFEEDFACE;
-  mp->input_queue = pointer_to_uword (tm->vl_input_queue);
-  strncpy ((char *) mp->name, "tcp_clients_tester", sizeof (mp->name) - 1);
-
-  vl_api_memclnt_create_t_handler (mp);
-
-  /* Wait for reply */
-  vlib_process_wait_for_event_or_clock (vm, 1.0);
-  event_type = vlib_process_get_events (vm, &event_data);
-  switch (event_type)
-    {
-    case 1:
-      resolved = 1;
-      break;
-    case ~0:
-      /* timed out */
-      break;
-    default:
-      clib_warning ("unknown event_type %d", event_type);
-    }
-  if (!resolved)
-    return -1;
-  return 0;
-}
-
-#define foreach_tclient_static_api_msg       	\
-_(MEMCLNT_CREATE_REPLY, memclnt_create_reply)   \
-
-static clib_error_t *
-tclient_api_hookup (vlib_main_t * vm)
-{
-  vl_msg_api_msg_config_t _c, *c = &_c;
-
-  /* Hook up client-side static APIs to our handlers */
-#define _(N,n) do {                                             \
-    c->id = VL_API_##N;                                         \
-    c->name = #n;                                               \
-    c->handler = vl_api_##n##_t_handler;                        \
-    c->cleanup = vl_noop_handler;                               \
-    c->endian = vl_api_##n##_t_endian;                          \
-    c->print = vl_api_##n##_t_print;                            \
-    c->size = sizeof(vl_api_##n##_t);                           \
-    c->traced = 1; /* trace, so these msgs print */             \
-    c->replay = 0; /* don't replay client create/delete msgs */ \
-    c->message_bounce = 0; /* don't bounce this message */	\
-    vl_msg_api_config(c);} while (0);
-
-  foreach_tclient_static_api_msg;
-#undef _
-
+  tm->my_client_index =
+    vl_api_memclnt_create_internal ("tcp_test_client", tm->vl_input_queue);
   return 0;
 }
 
@@ -400,7 +310,6 @@ tcp_test_clients_init (vlib_main_t * vm)
   u32 num_threads;
   int i;
 
-  tclient_api_hookup (vm);
   if (create_api_loopback (tm))
     return -1;
 
diff --git a/src/vnet/tcp/builtin_proxy.c b/src/vnet/tcp/builtin_proxy.c
new file mode 100644
index 00000000000..d8cfb11d315
--- /dev/null
+++ b/src/vnet/tcp/builtin_proxy.c
@@ -0,0 +1,599 @@
+/*
+* Copyright (c) 2015-2017 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 <vnet/vnet.h>
+#include <vlibmemory/api.h>
+#include <vnet/session/application.h>
+#include <vnet/session/application_interface.h>
+#include <vnet/tcp/builtin_proxy.h>
+
+builtin_proxy_main_t builtin_proxy_main;
+
+static void
+delete_proxy_session (stream_session_t * s, int is_active_open)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  proxy_session_t *ps = 0;
+  vnet_disconnect_args_t _a, *a = &_a;
+  stream_session_t *active_open_session = 0;
+  stream_session_t *server_session = 0;
+  uword *p;
+  u64 handle;
+
+  handle = stream_session_handle (s);
+
+  clib_spinlock_lock_if_init (&bpm->sessions_lock);
+  if (is_active_open)
+    {
+      active_open_session = s;
+
+      p = hash_get (bpm->proxy_session_by_active_open_handle, handle);
+      if (p == 0)
+	{
+	  clib_warning ("proxy session for %s handle %lld (%llx) AWOL",
+			is_active_open ? "active open" : "server",
+			handle, handle);
+	}
+      else
+	{
+	  ps = pool_elt_at_index (bpm->sessions, p[0]);
+	  if (ps->vpp_server_handle != ~0)
+	    server_session = stream_session_get_from_handle
+	      (ps->vpp_server_handle);
+	  else
+	    server_session = 0;
+	}
+    }
+  else
+    {
+      server_session = s;
+
+      p = hash_get (bpm->proxy_session_by_server_handle, handle);
+      if (p == 0)
+	{
+	  clib_warning ("proxy session for %s handle %lld (%llx) AWOL",
+			is_active_open ? "active open" : "server",
+			handle, handle);
+	}
+      else
+	{
+	  ps = pool_elt_at_index (bpm->sessions, p[0]);
+	  if (ps->vpp_server_handle != ~0)
+	    active_open_session = stream_session_get_from_handle
+	      (ps->vpp_server_handle);
+	  else
+	    active_open_session = 0;
+	}
+    }
+
+  if (ps)
+    {
+      if (CLIB_DEBUG > 0)
+	memset (ps, 0xFE, sizeof (*ps));
+      pool_put (bpm->sessions, ps);
+    }
+
+  clib_spinlock_unlock_if_init (&bpm->sessions_lock);
+
+  if (active_open_session)
+    {
+      a->handle = stream_session_handle (active_open_session);
+      a->app_index = bpm->active_open_app_index;
+      hash_unset (bpm->proxy_session_by_active_open_handle,
+		  stream_session_handle (active_open_session));
+      vnet_disconnect_session (a);
+    }
+
+  if (server_session)
+    {
+      a->handle = stream_session_handle (server_session);
+      a->app_index = bpm->server_app_index;
+      hash_unset (bpm->proxy_session_by_server_handle,
+		  stream_session_handle (server_session));
+      vnet_disconnect_session (a);
+    }
+}
+
+static int
+server_accept_callback (stream_session_t * s)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+
+  s->session_state = SESSION_STATE_READY;
+
+  clib_spinlock_lock_if_init (&bpm->sessions_lock);
+
+  return 0;
+}
+
+static void
+server_disconnect_callback (stream_session_t * s)
+{
+  delete_proxy_session (s, 0 /* is_active_open */ );
+}
+
+static void
+server_reset_callback (stream_session_t * s)
+{
+  clib_warning ("Reset session %U", format_stream_session, s, 2);
+  delete_proxy_session (s, 0 /* is_active_open */ );
+}
+
+static int
+server_connected_callback (u32 app_index, u32 api_context,
+			   stream_session_t * s, u8 is_fail)
+{
+  clib_warning ("called...");
+  return -1;
+}
+
+static int
+server_add_segment_callback (u32 client_index,
+			     const u8 * seg_name, u32 seg_size)
+{
+  clib_warning ("called...");
+  return -1;
+}
+
+static int
+server_redirect_connect_callback (u32 client_index, void *mp)
+{
+  clib_warning ("called...");
+  return -1;
+}
+
+static int
+server_rx_callback (stream_session_t * s)
+{
+  u32 max_dequeue;
+  int actual_transfer __attribute__ ((unused));
+  svm_fifo_t *tx_fifo, *rx_fifo;
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  u32 thread_index = vlib_get_thread_index ();
+  vnet_connect_args_t _a, *a = &_a;
+  proxy_session_t *ps;
+  int proxy_index;
+  uword *p;
+  svm_fifo_t *active_open_tx_fifo;
+  session_fifo_event_t evt;
+
+  ASSERT (s->thread_index == thread_index);
+
+  clib_spinlock_lock_if_init (&bpm->sessions_lock);
+  p =
+    hash_get (bpm->proxy_session_by_server_handle, stream_session_handle (s));
+
+  if (PREDICT_TRUE (p != 0))
+    {
+      clib_spinlock_unlock_if_init (&bpm->sessions_lock);
+      active_open_tx_fifo = s->server_rx_fifo;
+
+      /*
+       * Send event for active open tx fifo
+       */
+      if (svm_fifo_set_event (active_open_tx_fifo))
+	{
+	  evt.fifo = active_open_tx_fifo;
+	  evt.event_type = FIFO_EVENT_APP_TX;
+	  if (unix_shared_memory_queue_add
+	      (bpm->active_open_event_queue[thread_index], (u8 *) & evt,
+	       0 /* do wait for mutex */ ))
+	    clib_warning ("failed to enqueue tx evt");
+	}
+    }
+  else
+    {
+      rx_fifo = s->server_rx_fifo;
+      tx_fifo = s->server_tx_fifo;
+
+      ASSERT (rx_fifo->master_thread_index == thread_index);
+      ASSERT (tx_fifo->master_thread_index == thread_index);
+
+      max_dequeue = svm_fifo_max_dequeue (s->server_rx_fifo);
+
+      if (PREDICT_FALSE (max_dequeue == 0))
+	return 0;
+
+      actual_transfer = svm_fifo_peek (rx_fifo, 0 /* relative_offset */ ,
+				       max_dequeue,
+				       bpm->rx_buf[thread_index]);
+
+      /* $$$ your message in this space: parse url, etc. */
+
+      memset (a, 0, sizeof (*a));
+
+      clib_spinlock_lock_if_init (&bpm->sessions_lock);
+      pool_get (bpm->sessions, ps);
+      memset (ps, 0, sizeof (*ps));
+      ps->server_rx_fifo = rx_fifo;
+      ps->server_tx_fifo = tx_fifo;
+      ps->vpp_server_handle = stream_session_handle (s);
+
+      proxy_index = ps - bpm->sessions;
+
+      hash_set (bpm->proxy_session_by_server_handle, ps->vpp_server_handle,
+		proxy_index);
+
+      clib_spinlock_unlock_if_init (&bpm->sessions_lock);
+
+      a->uri = "tcp://6.0.2.2/23";
+      a->api_context = proxy_index;
+      a->app_index = bpm->active_open_app_index;
+      a->mp = 0;
+      vnet_connect_uri (a);
+    }
+
+  return 0;
+}
+
+static session_cb_vft_t builtin_session_cb_vft = {
+  .session_accept_callback = server_accept_callback,
+  .session_disconnect_callback = server_disconnect_callback,
+  .session_connected_callback = server_connected_callback,
+  .add_segment_callback = server_add_segment_callback,
+  .redirect_connect_callback = server_redirect_connect_callback,
+  .builtin_server_rx_callback = server_rx_callback,
+  .session_reset_callback = server_reset_callback
+};
+
+static int
+active_open_connected_callback (u32 app_index, u32 opaque,
+				stream_session_t * s, u8 is_fail)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  proxy_session_t *ps;
+  u8 thread_index = vlib_get_thread_index ();
+  session_fifo_event_t evt;
+
+  if (is_fail)
+    {
+      clib_warning ("connection %d failed!", opaque);
+      return 0;
+    }
+
+  /*
+   * Setup proxy session handle.
+   */
+  clib_spinlock_lock_if_init (&bpm->sessions_lock);
+
+  ps = pool_elt_at_index (bpm->sessions, opaque);
+  ps->vpp_active_open_handle = stream_session_handle (s);
+
+  s->server_tx_fifo = ps->server_rx_fifo;
+  s->server_rx_fifo = ps->server_tx_fifo;
+
+  /*
+   * Reset the active-open tx-fifo master indices so the active-open session
+   * will receive data, etc.
+   */
+  s->server_tx_fifo->master_session_index = s->session_index;
+  s->server_tx_fifo->master_thread_index = s->thread_index;
+
+  /*
+   * Account for the active-open session's use of the fifos
+   * so they won't disappear until the last session which uses
+   * them disappears
+   */
+  s->server_tx_fifo->refcnt++;
+  s->server_rx_fifo->refcnt++;
+
+  hash_set (bpm->proxy_session_by_active_open_handle,
+	    ps->vpp_active_open_handle, opaque);
+
+  clib_spinlock_unlock_if_init (&bpm->sessions_lock);
+
+  /*
+   * Send event for active open tx fifo
+   */
+  if (svm_fifo_set_event (s->server_tx_fifo))
+    {
+      evt.fifo = s->server_tx_fifo;
+      evt.event_type = FIFO_EVENT_APP_TX;
+      if (unix_shared_memory_queue_add
+	  (bpm->active_open_event_queue[thread_index], (u8 *) & evt,
+	   0 /* do wait for mutex */ ))
+	clib_warning ("failed to enqueue tx evt");
+    }
+
+  return 0;
+}
+
+static void
+active_open_reset_callback (stream_session_t * s)
+{
+  delete_proxy_session (s, 1 /* is_active_open */ );
+}
+
+static int
+active_open_create_callback (stream_session_t * s)
+{
+  return 0;
+}
+
+static void
+active_open_disconnect_callback (stream_session_t * s)
+{
+  delete_proxy_session (s, 1 /* is_active_open */ );
+}
+
+static int
+active_open_rx_callback (stream_session_t * s)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  session_fifo_event_t evt;
+  svm_fifo_t *server_rx_fifo;
+  u32 thread_index = vlib_get_thread_index ();
+
+  server_rx_fifo = s->server_rx_fifo;
+
+  /*
+   * Send event for server tx fifo
+   */
+  if (svm_fifo_set_event (server_rx_fifo))
+    {
+      evt.fifo = server_rx_fifo;
+      evt.event_type = FIFO_EVENT_APP_TX;
+      if (unix_shared_memory_queue_add
+	  (bpm->server_event_queue[thread_index], (u8 *) & evt,
+	   0 /* do wait for mutex */ ))
+	clib_warning ("failed to enqueue server rx evt");
+    }
+
+  return 0;
+}
+
+/* *INDENT-OFF* */
+static session_cb_vft_t builtin_clients = {
+  .session_reset_callback = active_open_reset_callback,
+  .session_connected_callback = active_open_connected_callback,
+  .session_accept_callback = active_open_create_callback,
+  .session_disconnect_callback = active_open_disconnect_callback,
+  .builtin_server_rx_callback = active_open_rx_callback
+};
+/* *INDENT-ON* */
+
+
+static void
+create_api_loopbacks (vlib_main_t * vm)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  api_main_t *am = &api_main;
+  vl_shmem_hdr_t *shmem_hdr;
+
+  shmem_hdr = am->shmem_hdr;
+  bpm->vl_input_queue = shmem_hdr->vl_input_queue;
+  bpm->server_client_index =
+    vl_api_memclnt_create_internal ("proxy_server", bpm->vl_input_queue);
+  bpm->active_open_client_index =
+    vl_api_memclnt_create_internal ("proxy_active_open", bpm->vl_input_queue);
+}
+
+static int
+server_attach ()
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  u8 segment_name[128];
+  u64 options[SESSION_OPTIONS_N_OPTIONS];
+  vnet_app_attach_args_t _a, *a = &_a;
+
+  memset (a, 0, sizeof (*a));
+  memset (options, 0, sizeof (options));
+
+  a->api_client_index = bpm->server_client_index;
+  a->session_cb_vft = &builtin_session_cb_vft;
+  a->options = options;
+  a->options[SESSION_OPTIONS_SEGMENT_SIZE] = 512 << 20;
+  a->options[SESSION_OPTIONS_RX_FIFO_SIZE] = bpm->fifo_size;
+  a->options[SESSION_OPTIONS_TX_FIFO_SIZE] = bpm->fifo_size;
+  a->options[APP_OPTIONS_PRIVATE_SEGMENT_COUNT] = bpm->private_segment_count;
+  a->options[APP_OPTIONS_PRIVATE_SEGMENT_SIZE] = bpm->private_segment_size;
+  a->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] =
+    bpm->prealloc_fifos ? bpm->prealloc_fifos : 1;
+
+  a->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP;
+
+  a->segment_name = segment_name;
+  a->segment_name_length = ARRAY_LEN (segment_name);
+
+  if (vnet_application_attach (a))
+    {
+      clib_warning ("failed to attach server");
+      return -1;
+    }
+  bpm->server_app_index = a->app_index;
+
+  return 0;
+}
+
+static int
+active_open_attach (void)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  vnet_app_attach_args_t _a, *a = &_a;
+  u8 segment_name[128];
+  u32 segment_name_length;
+  u64 options[16];
+
+  segment_name_length = ARRAY_LEN (segment_name);
+
+  memset (a, 0, sizeof (*a));
+  memset (options, 0, sizeof (options));
+
+  a->api_client_index = bpm->active_open_client_index;
+  a->segment_name = segment_name;
+  a->segment_name_length = segment_name_length;
+  a->session_cb_vft = &builtin_clients;
+
+  options[SESSION_OPTIONS_ACCEPT_COOKIE] = 0x12345678;
+  options[SESSION_OPTIONS_SEGMENT_SIZE] = 512 << 20;
+  options[SESSION_OPTIONS_RX_FIFO_SIZE] = bpm->fifo_size;
+  options[SESSION_OPTIONS_TX_FIFO_SIZE] = bpm->fifo_size;
+  options[APP_OPTIONS_PRIVATE_SEGMENT_COUNT] = bpm->private_segment_count;
+  options[APP_OPTIONS_PRIVATE_SEGMENT_SIZE] = bpm->private_segment_size;
+  options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] =
+    bpm->prealloc_fifos ? bpm->prealloc_fifos : 1;
+
+  options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP
+    | APP_OPTIONS_FLAGS_IS_PROXY;
+
+  a->options = options;
+
+  if (vnet_application_attach (a))
+    return -1;
+
+  bpm->active_open_app_index = a->app_index;
+
+  return 0;
+}
+
+static int
+server_listen ()
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  vnet_bind_args_t _a, *a = &_a;
+  memset (a, 0, sizeof (*a));
+  a->app_index = bpm->server_app_index;
+  a->uri = "tcp://0.0.0.0/23";
+  return vnet_bind_uri (a);
+}
+
+static int
+server_create (vlib_main_t * vm)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  vlib_thread_main_t *vtm = vlib_get_thread_main ();
+  u32 num_threads;
+  int i;
+
+  if (bpm->server_client_index == (u32) ~ 0)
+    create_api_loopbacks (vm);
+
+  num_threads = 1 /* main thread */  + vtm->n_threads;
+  vec_validate (builtin_proxy_main.server_event_queue, num_threads - 1);
+  vec_validate (builtin_proxy_main.active_open_event_queue, num_threads - 1);
+  vec_validate (bpm->rx_buf, num_threads - 1);
+
+  for (i = 0; i < num_threads; i++)
+    vec_validate (bpm->rx_buf[i], bpm->rcv_buffer_size);
+
+  if (server_attach ())
+    {
+      clib_warning ("failed to attach server app");
+      return -1;
+    }
+  if (server_listen ())
+    {
+      clib_warning ("failed to start listening");
+      return -1;
+    }
+  if (active_open_attach ())
+    {
+      clib_warning ("failed to attach active open app");
+      return -1;
+    }
+
+  for (i = 0; i < num_threads; i++)
+    {
+      bpm->active_open_event_queue[i] =
+	session_manager_get_vpp_event_queue (i);
+
+      ASSERT (bpm->active_open_event_queue[i]);
+
+      bpm->server_event_queue[i] = session_manager_get_vpp_event_queue (i);
+    }
+
+  return 0;
+}
+
+static clib_error_t *
+proxy_server_create_command_fn (vlib_main_t * vm, unformat_input_t * input,
+				vlib_cli_command_t * cmd)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  int rv;
+  u32 tmp;
+
+  bpm->fifo_size = 64 << 10;
+  bpm->rcv_buffer_size = 1024;
+  bpm->prealloc_fifos = 0;
+  bpm->private_segment_count = 0;
+  bpm->private_segment_size = 0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "fifo-size %d", &bpm->fifo_size))
+	bpm->fifo_size <<= 10;
+      else if (unformat (input, "rcv-buf-size %d", &bpm->rcv_buffer_size))
+	;
+      else if (unformat (input, "prealloc-fifos %d", &bpm->prealloc_fifos))
+	;
+      else if (unformat (input, "private-segment-count %d",
+			 &bpm->private_segment_count))
+	;
+      else if (unformat (input, "private-segment-size %dm", &tmp))
+	bpm->private_segment_size = tmp << 20;
+      else if (unformat (input, "private-segment-size %dg", &tmp))
+	bpm->private_segment_size = tmp << 30;
+      else if (unformat (input, "private-segment-size %d", &tmp))
+	bpm->private_segment_size = tmp;
+      else
+	return clib_error_return (0, "unknown input `%U'",
+				  format_unformat_error, input);
+    }
+
+  vnet_session_enable_disable (vm, 1 /* turn on TCP, etc. */ );
+
+  rv = server_create (vm);
+  switch (rv)
+    {
+    case 0:
+      break;
+    default:
+      return clib_error_return (0, "server_create returned %d", rv);
+    }
+
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (server_create_command, static) =
+{
+  .path = "test proxy server",
+  .short_help = "test proxy server",
+  .function = proxy_server_create_command_fn,
+};
+/* *INDENT-ON* */
+
+clib_error_t *
+builtin_tcp_proxy_main_init (vlib_main_t * vm)
+{
+  builtin_proxy_main_t *bpm = &builtin_proxy_main;
+  bpm->server_client_index = ~0;
+  bpm->active_open_client_index = ~0;
+  bpm->proxy_session_by_active_open_handle = hash_create (0, sizeof (uword));
+  bpm->proxy_session_by_server_handle = hash_create (0, sizeof (uword));
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (builtin_tcp_proxy_main_init);
+
+/*
+* fd.io coding-style-patch-verification: ON
+*
+* Local Variables:
+* eval: (c-set-style "gnu")
+* End:
+*/
diff --git a/src/vnet/tcp/builtin_proxy.h b/src/vnet/tcp/builtin_proxy.h
new file mode 100644
index 00000000000..cf707a150cf
--- /dev/null
+++ b/src/vnet/tcp/builtin_proxy.h
@@ -0,0 +1,100 @@
+
+/*
+ * builtin_proxy.h - skeleton vpp engine plug-in header file
+ *
+ * Copyright (c) <current-year> <your-organization>
+ * 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.
+ */
+#ifndef __included_builtin_proxy_h__
+#define __included_builtin_proxy_h__
+
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+
+#include <vppinfra/hash.h>
+#include <vppinfra/error.h>
+#include <vlibmemory/unix_shared_memory_queue.h>
+#include <svm/svm_fifo_segment.h>
+#include <vnet/session/session.h>
+#include <vnet/session/application_interface.h>
+
+typedef struct
+{
+  svm_fifo_t *server_rx_fifo;
+  svm_fifo_t *server_tx_fifo;
+
+  u64 vpp_server_handle;
+  u64 vpp_active_open_handle;
+} proxy_session_t;
+
+typedef struct
+{
+  unix_shared_memory_queue_t *vl_input_queue;	/**< vpe input queue */
+  /** per-thread vectors */
+  unix_shared_memory_queue_t **server_event_queue;
+  unix_shared_memory_queue_t **active_open_event_queue;
+  u8 **rx_buf;				/**< intermediate rx buffers */
+
+  u32 cli_node_index;			/**< cli process node index */
+  u32 server_client_index;		/**< server API client handle */
+  u32 server_app_index;			/**< server app index */
+  u32 active_open_client_index;		/**< active open API client handle */
+  u32 active_open_app_index;		/**< active open index after attach */
+
+  uword *proxy_session_by_server_handle;
+  uword *proxy_session_by_active_open_handle;
+
+  /*
+   * Configuration params
+   */
+  u8 *connect_uri;			/**< URI for slave's connect */
+  u32 configured_segment_size;
+  u32 fifo_size;
+  u32 private_segment_count;		/**< Number of private fifo segs */
+  u32 private_segment_size;		/**< size of private fifo segs */
+  int rcv_buffer_size;
+
+  /*
+   * Test state variables
+   */
+  proxy_session_t *sessions;		/**< Session pool, shared */
+  clib_spinlock_t sessions_lock;
+  u32 **connection_index_by_thread;
+  pthread_t client_thread_handle;
+
+  /*
+   * Flags
+   */
+  u8 is_init;
+  u8 prealloc_fifos;		/**< Request fifo preallocation */
+
+  /*
+   * Convenience
+   */
+  vlib_main_t *vlib_main;
+  vnet_main_t *vnet_main;
+  ethernet_main_t *ethernet_main;
+} builtin_proxy_main_t;
+
+builtin_proxy_main_t builtin_proxy_main;
+
+#endif /* __included_builtin_proxy_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/tcp/builtin_server.c b/src/vnet/tcp/builtin_server.c
index 3416678ead6..2454a831ad7 100644
--- a/src/vnet/tcp/builtin_server.c
+++ b/src/vnet/tcp/builtin_server.c
@@ -18,25 +18,6 @@
 #include <vnet/session/application.h>
 #include <vnet/session/application_interface.h>
 
-/* define message IDs */
-#include <vpp/api/vpe_msg_enum.h>
-
-/* define message structures */
-#define vl_typedefs
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_typedefs
-
-/* define generated endian-swappers */
-#define vl_endianfun
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_endianfun
-
-/* instantiate all the print functions we know about */
-#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
-#define vl_printfun
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_printfun
-
 typedef struct
 {
   /*
@@ -279,46 +260,13 @@ static int
 create_api_loopback (vlib_main_t * vm)
 {
   builtin_server_main_t *bsm = &builtin_server_main;
-  vl_api_memclnt_create_t _m, *mp = &_m;
-  extern void vl_api_memclnt_create_t_handler (vl_api_memclnt_create_t *);
   api_main_t *am = &api_main;
   vl_shmem_hdr_t *shmem_hdr;
-  uword *event_data = 0, event_type;
-  int resolved = 0;
-
-  /*
-   * Create a "loopback" API client connection
-   * Don't do things like this unless you know what you're doing...
-   */
 
   shmem_hdr = am->shmem_hdr;
   bsm->vl_input_queue = shmem_hdr->vl_input_queue;
-  memset (mp, 0, sizeof (*mp));
-  mp->_vl_msg_id = VL_API_MEMCLNT_CREATE;
-  mp->context = 0xFEEDFACE;
-  mp->input_queue = pointer_to_uword (bsm->vl_input_queue);
-  strncpy ((char *) mp->name, "tcp_test_server", sizeof (mp->name) - 1);
-
-  vl_api_memclnt_create_t_handler (mp);
-
-  /* Wait for reply */
-  bsm->node_index = vlib_get_current_process (vm)->node_runtime.node_index;
-  vlib_process_wait_for_event_or_clock (vm, 2.0);
-  event_type = vlib_process_get_events (vm, &event_data);
-  switch (event_type)
-    {
-    case 1:
-      resolved = 1;
-      break;
-    case ~0:
-      /* timed out */
-      break;
-    default:
-      clib_warning ("unknown event_type %d", event_type);
-    }
-  if (!resolved)
-    return -1;
-
+  bsm->my_client_index =
+    vl_api_memclnt_create_internal ("tcp_test_server", bsm->vl_input_queue);
   return 0;
 }
 
@@ -413,45 +361,6 @@ server_create (vlib_main_t * vm)
   return 0;
 }
 
-/* Get our api client index */
-static void
-vl_api_memclnt_create_reply_t_handler (vl_api_memclnt_create_reply_t * mp)
-{
-  vlib_main_t *vm = vlib_get_main ();
-  builtin_server_main_t *bsm = &builtin_server_main;
-  bsm->my_client_index = mp->index;
-  vlib_process_signal_event (vm, bsm->node_index, 1 /* evt */ ,
-			     0 /* data */ );
-}
-
-#define foreach_tcp_builtin_server_api_msg      		\
-_(MEMCLNT_CREATE_REPLY, memclnt_create_reply)   		\
-
-static clib_error_t *
-tcp_builtin_server_api_hookup (vlib_main_t * vm)
-{
-  vl_msg_api_msg_config_t _c, *c = &_c;
-
-  /* Hook up client-side static APIs to our handlers */
-#define _(N,n) do {                                             \
-    c->id = VL_API_##N;                                         \
-    c->name = #n;                                               \
-    c->handler = vl_api_##n##_t_handler;                        \
-    c->cleanup = vl_noop_handler;                               \
-    c->endian = vl_api_##n##_t_endian;                          \
-    c->print = vl_api_##n##_t_print;                            \
-    c->size = sizeof(vl_api_##n##_t);                           \
-    c->traced = 1; /* trace, so these msgs print */             \
-    c->replay = 0; /* don't replay client create/delete msgs */ \
-    c->message_bounce = 0; /* don't bounce this message */	\
-    vl_msg_api_config(c);} while (0);
-
-  foreach_tcp_builtin_server_api_msg;
-#undef _
-
-  return 0;
-}
-
 static clib_error_t *
 server_create_command_fn (vlib_main_t * vm, unformat_input_t * input,
 			  vlib_cli_command_t * cmd)
@@ -491,7 +400,6 @@ server_create_command_fn (vlib_main_t * vm, unformat_input_t * input,
 				  format_unformat_error, input);
     }
 
-  tcp_builtin_server_api_hookup (vm);
   vnet_session_enable_disable (vm, 1 /* turn on TCP, etc. */ );
 
   rv = server_create (vm);