TCP proxy prototype
[vpp.git] / src / vnet / session / session.c
index d0792fa..991bcd5 100644 (file)
  */
 
 #include <vnet/session/session.h>
+#include <vnet/session/session_debug.h>
+#include <vnet/session/application.h>
 #include <vlibmemory/api.h>
 #include <vnet/dpo/load_balance.h>
 #include <vnet/fib/ip4_fib.h>
-#include <vnet/session/application.h>
 #include <vnet/tcp/tcp.h>
-#include <vnet/session/session_debug.h>
-
-/**
- * Per-type vector of transport protocol virtual function tables
- */
-static transport_proto_vft_t *tp_vfts;
 
 session_manager_main_t session_manager_main;
-
-/*
- * Session lookup key; (src-ip, dst-ip, src-port, dst-port, session-type)
- * Value: (owner thread index << 32 | session_index);
- */
-void
-stream_session_table_add_for_tc (transport_connection_t * tc, u64 value)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv4_t kv4;
-  session_kv6_t kv6;
-
-  switch (tc->proto)
-    {
-    case SESSION_TYPE_IP4_UDP:
-    case SESSION_TYPE_IP4_TCP:
-      make_v4_ss_kv_from_tc (&kv4, tc);
-      kv4.value = value;
-      clib_bihash_add_del_16_8 (&smm->v4_session_hash, &kv4, 1 /* is_add */ );
-      break;
-    case SESSION_TYPE_IP6_UDP:
-    case SESSION_TYPE_IP6_TCP:
-      make_v6_ss_kv_from_tc (&kv6, tc);
-      kv6.value = value;
-      clib_bihash_add_del_48_8 (&smm->v6_session_hash, &kv6, 1 /* is_add */ );
-      break;
-    default:
-      clib_warning ("Session type not supported");
-      ASSERT (0);
-    }
-}
-
-void
-stream_session_table_add (session_manager_main_t * smm, stream_session_t * s,
-                         u64 value)
-{
-  transport_connection_t *tc;
-
-  tc = tp_vfts[s->session_type].get_connection (s->connection_index,
-                                               s->thread_index);
-  stream_session_table_add_for_tc (tc, value);
-}
-
-static void
-stream_session_half_open_table_add (session_type_t sst,
-                                   transport_connection_t * tc, u64 value)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv4_t kv4;
-  session_kv6_t kv6;
-
-  switch (sst)
-    {
-    case SESSION_TYPE_IP4_UDP:
-    case SESSION_TYPE_IP4_TCP:
-      make_v4_ss_kv_from_tc (&kv4, tc);
-      kv4.value = value;
-      clib_bihash_add_del_16_8 (&smm->v4_half_open_hash, &kv4,
-                               1 /* is_add */ );
-      break;
-    case SESSION_TYPE_IP6_UDP:
-    case SESSION_TYPE_IP6_TCP:
-      make_v6_ss_kv_from_tc (&kv6, tc);
-      kv6.value = value;
-      clib_bihash_add_del_48_8 (&smm->v6_half_open_hash, &kv6,
-                               1 /* is_add */ );
-      break;
-    default:
-      clib_warning ("Session type not supported");
-      ASSERT (0);
-    }
-}
-
-int
-stream_session_table_del_for_tc (transport_connection_t * tc)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv4_t kv4;
-  session_kv6_t kv6;
-  switch (tc->proto)
-    {
-    case SESSION_TYPE_IP4_UDP:
-    case SESSION_TYPE_IP4_TCP:
-      make_v4_ss_kv_from_tc (&kv4, tc);
-      return clib_bihash_add_del_16_8 (&smm->v4_session_hash, &kv4,
-                                      0 /* is_add */ );
-      break;
-    case SESSION_TYPE_IP6_UDP:
-    case SESSION_TYPE_IP6_TCP:
-      make_v6_ss_kv_from_tc (&kv6, tc);
-      return clib_bihash_add_del_48_8 (&smm->v6_session_hash, &kv6,
-                                      0 /* is_add */ );
-      break;
-    default:
-      clib_warning ("Session type not supported");
-      ASSERT (0);
-    }
-
-  return 0;
-}
-
-static int
-stream_session_table_del (session_manager_main_t * smm, stream_session_t * s)
-{
-  transport_connection_t *ts;
-
-  ts = tp_vfts[s->session_type].get_connection (s->connection_index,
-                                               s->thread_index);
-  return stream_session_table_del_for_tc (ts);
-}
-
-static void
-stream_session_half_open_table_del (session_manager_main_t * smm, u8 sst,
-                                   transport_connection_t * tc)
-{
-  session_kv4_t kv4;
-  session_kv6_t kv6;
-
-  switch (sst)
-    {
-    case SESSION_TYPE_IP4_UDP:
-    case SESSION_TYPE_IP4_TCP:
-      make_v4_ss_kv_from_tc (&kv4, tc);
-      clib_bihash_add_del_16_8 (&smm->v4_half_open_hash, &kv4,
-                               0 /* is_add */ );
-      break;
-    case SESSION_TYPE_IP6_UDP:
-    case SESSION_TYPE_IP6_TCP:
-      make_v6_ss_kv_from_tc (&kv6, tc);
-      clib_bihash_add_del_48_8 (&smm->v6_half_open_hash, &kv6,
-                               0 /* is_add */ );
-      break;
-    default:
-      clib_warning ("Session type not supported");
-      ASSERT (0);
-    }
-}
-
-stream_session_t *
-stream_session_lookup_listener4 (ip4_address_t * lcl, u16 lcl_port, u8 proto)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv4_t kv4;
-  int rv;
-
-  make_v4_listener_kv (&kv4, lcl, lcl_port, proto);
-  rv = clib_bihash_search_inline_16_8 (&smm->v4_session_hash, &kv4);
-  if (rv == 0)
-    return pool_elt_at_index (smm->listen_sessions[proto], (u32) kv4.value);
-
-  /* Zero out the lcl ip */
-  kv4.key[0] = 0;
-  rv = clib_bihash_search_inline_16_8 (&smm->v4_session_hash, &kv4);
-  if (rv == 0)
-    return pool_elt_at_index (smm->listen_sessions[proto], kv4.value);
-
-  return 0;
-}
-
-/** Looks up a session based on the 5-tuple passed as argument.
- *
- * First it tries to find an established session, if this fails, it tries
- * finding a listener session if this fails, it tries a lookup with a
- * wildcarded local source (listener bound to all interfaces)
- */
-stream_session_t *
-stream_session_lookup4 (ip4_address_t * lcl, ip4_address_t * rmt,
-                       u16 lcl_port, u16 rmt_port, u8 proto,
-                       u32 my_thread_index)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv4_t kv4;
-  int rv;
-
-  /* Lookup session amongst established ones */
-  make_v4_ss_kv (&kv4, lcl, rmt, lcl_port, rmt_port, proto);
-  rv = clib_bihash_search_inline_16_8 (&smm->v4_session_hash, &kv4);
-  if (rv == 0)
-    return stream_session_get_tsi (kv4.value, my_thread_index);
-
-  /* If nothing is found, check if any listener is available */
-  return stream_session_lookup_listener4 (lcl, lcl_port, proto);
-}
-
-stream_session_t *
-stream_session_lookup_listener6 (ip6_address_t * lcl, u16 lcl_port, u8 proto)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv6_t kv6;
-  int rv;
-
-  make_v6_listener_kv (&kv6, lcl, lcl_port, proto);
-  rv = clib_bihash_search_inline_48_8 (&smm->v6_session_hash, &kv6);
-  if (rv == 0)
-    return pool_elt_at_index (smm->listen_sessions[proto], kv6.value);
-
-  /* Zero out the lcl ip */
-  kv6.key[0] = kv6.key[1] = 0;
-  rv = clib_bihash_search_inline_48_8 (&smm->v6_session_hash, &kv6);
-  if (rv == 0)
-    return pool_elt_at_index (smm->listen_sessions[proto], kv6.value);
-
-  return 0;
-}
-
-/* Looks up a session based on the 5-tuple passed as argument.
- * First it tries to find an established session, if this fails, it tries
- * finding a listener session if this fails, it tries a lookup with a
- * wildcarded local source (listener bound to all interfaces) */
-stream_session_t *
-stream_session_lookup6 (ip6_address_t * lcl, ip6_address_t * rmt,
-                       u16 lcl_port, u16 rmt_port, u8 proto,
-                       u32 my_thread_index)
-{
-  session_manager_main_t *smm = vnet_get_session_manager_main ();
-  session_kv6_t kv6;
-  int rv;
-
-  make_v6_ss_kv (&kv6, lcl, rmt, lcl_port, rmt_port, proto);
-  rv = clib_bihash_search_inline_48_8 (&smm->v6_session_hash, &kv6);
-  if (rv == 0)
-    return stream_session_get_tsi (kv6.value, my_thread_index);
-
-  /* If nothing is found, check if any listener is available */
-  return stream_session_lookup_listener6 (lcl, lcl_port, proto);
-}
-
-stream_session_t *
-stream_session_lookup_listener (ip46_address_t * lcl, u16 lcl_port, u8 proto)
-{
-  switch (proto)
-    {
-    case SESSION_TYPE_IP4_UDP:
-    case SESSION_TYPE_IP4_TCP:
-      return stream_session_lookup_listener4 (&lcl->ip4, lcl_port, proto);
-      break;
-    case SESSION_TYPE_IP6_UDP:
-    case SESSION_TYPE_IP6_TCP:
-      return stream_session_lookup_listener6 (&lcl->ip6, lcl_port, proto);
-      break;
-    }
-  return 0;
-}
-
-static u64
-stream_session_half_open_lookup (session_manager_main_t * smm,
-                                ip46_address_t * lcl, ip46_address_t * rmt,
-                                u16 lcl_port, u16 rmt_port, u8 proto)
-{
-  session_kv4_t kv4;
-  session_kv6_t kv6;
-  int rv;
-
-  switch (proto)
-    {
-    case SESSION_TYPE_IP4_UDP:
-    case SESSION_TYPE_IP4_TCP:
-      make_v4_ss_kv (&kv4, &lcl->ip4, &rmt->ip4, lcl_port, rmt_port, proto);
-      rv = clib_bihash_search_inline_16_8 (&smm->v4_half_open_hash, &kv4);
-
-      if (rv == 0)
-       return kv4.value;
-
-      return (u64) ~ 0;
-      break;
-    case SESSION_TYPE_IP6_UDP:
-    case SESSION_TYPE_IP6_TCP:
-      make_v6_ss_kv (&kv6, &lcl->ip6, &rmt->ip6, lcl_port, rmt_port, proto);
-      rv = clib_bihash_search_inline_48_8 (&smm->v6_half_open_hash, &kv6);
-
-      if (rv == 0)
-       return kv6.value;
-
-      return (u64) ~ 0;
-      break;
-    }
-  return 0;
-}
-
-transport_connection_t *
-stream_session_lookup_transport4 (ip4_address_t * lcl, ip4_address_t * rmt,
-                                 u16 lcl_port, u16 rmt_port, u8 proto,
-                                 u32 my_thread_index)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  session_kv4_t kv4;
-  stream_session_t *s;
-  int rv;
-
-  /* Lookup session amongst established ones */
-  make_v4_ss_kv (&kv4, lcl, rmt, lcl_port, rmt_port, proto);
-  rv = clib_bihash_search_inline_16_8 (&smm->v4_session_hash, &kv4);
-  if (rv == 0)
-    {
-      s = stream_session_get_tsi (kv4.value, my_thread_index);
-
-      return tp_vfts[s->session_type].get_connection (s->connection_index,
-                                                     my_thread_index);
-    }
-
-  /* If nothing is found, check if any listener is available */
-  s = stream_session_lookup_listener4 (lcl, lcl_port, proto);
-  if (s)
-    return tp_vfts[s->session_type].get_listener (s->connection_index);
-
-  /* Finally, try half-open connections */
-  rv = clib_bihash_search_inline_16_8 (&smm->v4_half_open_hash, &kv4);
-  if (rv == 0)
-    return tp_vfts[proto].get_half_open (kv4.value & 0xFFFFFFFF);
-
-  return 0;
-}
-
-transport_connection_t *
-stream_session_lookup_transport6 (ip6_address_t * lcl, ip6_address_t * rmt,
-                                 u16 lcl_port, u16 rmt_port, u8 proto,
-                                 u32 my_thread_index)
-{
-  session_manager_main_t *smm = &session_manager_main;
-  stream_session_t *s;
-  session_kv6_t kv6;
-  int rv;
-
-  make_v6_ss_kv (&kv6, lcl, rmt, lcl_port, rmt_port, proto);
-  rv = clib_bihash_search_inline_48_8 (&smm->v6_session_hash, &kv6);
-  if (rv == 0)
-    {
-      s = stream_session_get_tsi (kv6.value, my_thread_index);
-
-      return tp_vfts[s->session_type].get_connection (s->connection_index,
-                                                     my_thread_index);
-    }
-
-  /* If nothing is found, check if any listener is available */
-  s = stream_session_lookup_listener6 (lcl, lcl_port, proto);
-  if (s)
-    return tp_vfts[s->session_type].get_listener (s->connection_index);
-
-  /* Finally, try half-open connections */
-  rv = clib_bihash_search_inline_48_8 (&smm->v6_half_open_hash, &kv6);
-  if (rv == 0)
-    return tp_vfts[proto].get_half_open (kv6.value & 0xFFFFFFFF);
-
-  return 0;
-}
+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;
@@ -390,30 +41,39 @@ stream_session_create_i (segment_manager_t * sm, transport_connection_t * tc,
   u32 thread_index = tc->thread_index;
   int rv;
 
-  if ((rv = segment_manager_alloc_session_fifos (sm, &server_rx_fifo,
-                                                &server_tx_fifo,
-                                                &fifo_segment_index)))
-    return rv;
+  ASSERT (thread_index == vlib_get_thread_index ());
 
   /* 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 = tc->proto;
+  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;
 
@@ -424,7 +84,7 @@ stream_session_create_i (segment_manager_t * sm, transport_connection_t * tc,
   tc->s_index = s->session_index;
 
   /* Add to the main lookup table */
-  value = (((u64) thread_index) << 32) | (u64) s->session_index;
+  value = stream_session_handle (s);
   stream_session_table_add_for_tc (tc, value);
 
   *ret_s = s;
@@ -551,7 +211,7 @@ u8
 stream_session_no_space (transport_connection_t * tc, u32 thread_index,
                         u16 data_len)
 {
-  stream_session_t *s = stream_session_get (tc->c_index, thread_index);
+  stream_session_t *s = stream_session_get (tc->s_index, thread_index);
 
   if (PREDICT_FALSE (s->session_state != SESSION_STATE_READY))
     return 1;
@@ -563,6 +223,15 @@ stream_session_no_space (transport_connection_t * tc, u32 thread_index,
 }
 
 u32
+stream_session_tx_fifo_max_dequeue (transport_connection_t * tc)
+{
+  stream_session_t *s = stream_session_get (tc->s_index, tc->thread_index);
+  if (s->session_state != SESSION_STATE_READY)
+    return 0;
+  return svm_fifo_max_dequeue (s->server_tx_fifo);
+}
+
+int
 stream_session_peek_bytes (transport_connection_t * tc, u8 * buffer,
                           u32 offset, u32 max_bytes)
 {
@@ -691,23 +360,22 @@ stream_session_init_fifos_pointers (transport_connection_t * tc,
   svm_fifo_init_pointers (s->server_tx_fifo, tx_pointer);
 }
 
-void
-stream_session_connect_notify (transport_connection_t * tc, u8 sst,
-                              u8 is_fail)
+int
+stream_session_connect_notify (transport_connection_t * tc, u8 is_fail)
 {
-  session_manager_main_t *smm = &session_manager_main;
   application_t *app;
   stream_session_t *new_s = 0;
   u64 handle;
   u32 api_context = 0;
+  int error = 0;
 
-  handle = stream_session_half_open_lookup (smm, &tc->lcl_ip, &tc->rmt_ip,
-                                           tc->lcl_port, tc->rmt_port,
-                                           tc->proto);
+  handle = stream_session_half_open_lookup_handle (&tc->lcl_ip, &tc->rmt_ip,
+                                                  tc->lcl_port, tc->rmt_port,
+                                                  tc->transport_proto);
   if (handle == HALF_OPEN_LOOKUP_INVALID_VALUE)
     {
       clib_warning ("This can't be good!");
-      return;
+      return -1;
     }
 
   /* Get the app's index from the handle we stored when opening connection */
@@ -717,25 +385,37 @@ stream_session_connect_notify (transport_connection_t * tc, u8 sst,
   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))
-       return;
-
-      new_s->app_index = app->index;
+      if (stream_session_create_i (sm, tc, alloc_fifos, &new_s))
+       {
+         is_fail = 1;
+         error = -1;
+       }
+      else
+       new_s->app_index = app->index;
     }
 
-  /* Notify client */
-  app->cb_fns.session_connected_callback (app->index, api_context, new_s,
-                                         is_fail);
+  /* Notify client application */
+  if (app->cb_fns.session_connected_callback (app->index, api_context, new_s,
+                                             is_fail))
+    {
+      clib_warning ("failed to notify app");
+      if (!is_fail)
+       stream_session_disconnect (new_s);
+    }
+  else
+    {
+      if (!is_fail)
+       new_s->session_state = SESSION_STATE_READY;
+    }
 
   /* Cleanup session lookup */
-  stream_session_half_open_table_del (smm, sst, tc);
+  stream_session_half_open_table_del (tc);
 
-  /* Add to established lookup table */
-  handle = (((u64) tc->thread_index) << 32) | (u64) new_s->session_index;
-  stream_session_table_add_for_tc (tc, handle);
+  return error;
 }
 
 void
@@ -774,15 +454,19 @@ void
 stream_session_delete (stream_session_t * s)
 {
   session_manager_main_t *smm = vnet_get_session_manager_main ();
+  int rv;
 
   /* Delete from the main lookup table. */
-  stream_session_table_del (smm, s);
+  if ((rv = stream_session_table_del (s)))
+    clib_warning ("hash delete error, rv %d", rv);
 
   /* Cleanup fifo segments */
   segment_manager_dealloc_fifos (s->svm_segment_index, s->server_rx_fifo,
                                 s->server_tx_fifo);
 
   pool_put (smm->sessions[s->thread_index], s);
+  if (CLIB_DEBUG)
+    memset (s, 0xFA, sizeof (*s));
 }
 
 /**
@@ -838,11 +522,12 @@ 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;
   s->listener_index = listener_index;
+  s->session_state = SESSION_STATE_ACCEPTING;
 
   /* Shoulder-tap the server */
   if (notify)
@@ -867,14 +552,14 @@ stream_session_accept (transport_connection_t * tc, u32 listener_index,
  */
 int
 stream_session_open (u32 app_index, session_type_t st,
-                    transport_endpoint_t * tep,
+                    transport_endpoint_t * rmt,
                     transport_connection_t ** res)
 {
   transport_connection_t *tc;
   int rv;
   u64 handle;
 
-  rv = tp_vfts[st].open (&tep->ip, tep->port);
+  rv = tp_vfts[st].open (rmt);
   if (rv < 0)
     {
       clib_warning ("Transport failed to open connection.");
@@ -889,7 +574,7 @@ stream_session_open (u32 app_index, session_type_t st,
   handle = (((u64) app_index) << 32) | (u64) tc->c_index;
 
   /* Add to the half-open lookup table */
-  stream_session_half_open_table_add (st, tc, handle);
+  stream_session_half_open_table_add (tc, handle);
 
   *res = tc;
 
@@ -911,7 +596,7 @@ stream_session_listen (stream_session_t * s, transport_endpoint_t * tep)
   u32 tci;
 
   /* Transport bind/listen  */
-  tci = tp_vfts[s->session_type].bind (s->session_index, &tep->ip, tep->port);
+  tci = tp_vfts[s->session_type].bind (s->session_index, tep);
 
   if (tci == (u32) ~ 0)
     return -1;
@@ -976,8 +661,13 @@ session_send_session_evt_to_thread (u64 session_handle,
 
   /* Based on request block (or not) for lack of space */
   if (PREDICT_TRUE (q->cursize < q->maxsize))
-    unix_shared_memory_queue_add (q, (u8 *) & evt,
-                                 0 /* do wait for mutex */ );
+    {
+      if (unix_shared_memory_queue_add (q, (u8 *) & evt,
+                                       1 /* do wait for mutex */ ))
+       {
+         clib_warning ("failed to enqueue evt");
+       }
+    }
   else
     {
       clib_warning ("queue full");
@@ -1008,41 +698,18 @@ stream_session_disconnect (stream_session_t * s)
 void
 stream_session_cleanup (stream_session_t * s)
 {
-  session_manager_main_t *smm = &session_manager_main;
   int rv;
 
   s->session_state = SESSION_STATE_CLOSED;
 
   /* Delete from the main lookup table to avoid more enqueues */
-  rv = stream_session_table_del (smm, s);
+  rv = stream_session_table_del (s);
   if (rv)
     clib_warning ("hash delete error, rv %d", rv);
 
   tp_vfts[s->session_type].cleanup (s->connection_index, s->thread_index);
 }
 
-void
-session_register_transport (u8 type, const transport_proto_vft_t * vft)
-{
-  session_manager_main_t *smm = vnet_get_session_manager_main ();
-
-  vec_validate (tp_vfts, type);
-  tp_vfts[type] = *vft;
-
-  /* If an offset function is provided, then peek instead of dequeue */
-  smm->session_tx_fns[type] =
-    (vft->tx_fifo_offset) ? session_tx_fifo_peek_and_snd :
-    session_tx_fifo_dequeue_and_snd;
-}
-
-transport_proto_vft_t *
-session_get_transport_vft (u8 type)
-{
-  if (type >= vec_len (tp_vfts))
-    return 0;
-  return &tp_vfts[type];
-}
-
 /**
  * Allocate vpp event queue (once) per worker thread
  */
@@ -1052,30 +719,54 @@ session_vpp_event_queue_allocate (session_manager_main_t * smm,
 {
   api_main_t *am = &api_main;
   void *oldheap;
+  u32 event_queue_length = 2048;
 
   if (smm->vpp_event_queues[thread_index] == 0)
     {
       /* Allocate event fifo in the /vpe-api shared-memory segment */
       oldheap = svm_push_data_heap (am->vlib_rp);
 
+      if (smm->configured_event_queue_length)
+       event_queue_length = smm->configured_event_queue_length;
+
       smm->vpp_event_queues[thread_index] =
-       unix_shared_memory_queue_init (2048 /* nels $$$$ config */ ,
-                                      sizeof (session_fifo_event_t),
-                                      0 /* consumer pid */ ,
-                                      0
-                                      /* (do not) send signal when queue non-empty */
-       );
+       unix_shared_memory_queue_init
+       (event_queue_length,
+        sizeof (session_fifo_event_t), 0 /* consumer pid */ ,
+        0 /* (do not) send signal when queue non-empty */ );
 
       svm_pop_heap (oldheap);
     }
 }
 
+session_type_t
+session_type_from_proto_and_ip (transport_proto_t proto, u8 is_ip4)
+{
+  if (proto == TRANSPORT_PROTO_TCP)
+    {
+      if (is_ip4)
+       return SESSION_TYPE_IP4_TCP;
+      else
+       return SESSION_TYPE_IP6_TCP;
+    }
+  else
+    {
+      if (is_ip4)
+       return SESSION_TYPE_IP4_UDP;
+      else
+       return SESSION_TYPE_IP6_UDP;
+    }
+
+  return SESSION_N_TYPES;
+}
+
 static clib_error_t *
 session_manager_main_enable (vlib_main_t * vm)
 {
   session_manager_main_t *smm = &session_manager_main;
   vlib_thread_main_t *vtm = vlib_get_thread_main ();
   u32 num_threads;
+  u32 preallocated_sessions_per_worker;
   int i;
 
   num_threads = 1 /* main thread */  + vtm->n_threads;
@@ -1091,11 +782,19 @@ session_manager_main_enable (vlib_main_t * vm)
   vec_validate (smm->sessions, num_threads - 1);
   vec_validate (smm->session_indices_to_enqueue_by_thread, num_threads - 1);
   vec_validate (smm->tx_buffers, num_threads - 1);
-  vec_validate (smm->fifo_events, num_threads - 1);
-  vec_validate (smm->evts_partially_read, num_threads - 1);
+  vec_validate (smm->pending_event_vector, num_threads - 1);
+  vec_validate (smm->free_event_vector, num_threads - 1);
   vec_validate (smm->current_enqueue_epoch, num_threads - 1);
   vec_validate (smm->vpp_event_queues, num_threads - 1);
 
+  for (i = 0; i < num_threads; i++)
+    {
+      vec_validate (smm->free_event_vector[i], 0);
+      _vec_len (smm->free_event_vector[i]) = 0;
+      vec_validate (smm->pending_event_vector[i], 0);
+      _vec_len (smm->pending_event_vector[i]) = 0;
+    }
+
 #if SESSION_DBG
   vec_validate (smm->last_event_poll_by_thread, num_threads - 1);
 #endif
@@ -1104,30 +803,37 @@ session_manager_main_enable (vlib_main_t * vm)
   for (i = 0; i < vec_len (smm->vpp_event_queues); i++)
     session_vpp_event_queue_allocate (smm, i);
 
-  /* $$$$ preallocate hack config parameter */
-  for (i = 0; i < 200000; i++)
+  /* Preallocate sessions */
+  if (num_threads == 1)
     {
-      stream_session_t *ss;
-      pool_get_aligned (smm->sessions[0], ss, CLIB_CACHE_LINE_BYTES);
-      memset (ss, 0, sizeof (*ss));
-    }
+      for (i = 0; i < smm->preallocated_sessions; i++)
+       {
+         stream_session_t *ss __attribute__ ((unused));
+         pool_get_aligned (smm->sessions[0], ss, CLIB_CACHE_LINE_BYTES);
+       }
 
-  for (i = 0; i < 200000; i++)
-    pool_put_index (smm->sessions[0], i);
+      for (i = 0; i < smm->preallocated_sessions; i++)
+       pool_put_index (smm->sessions[0], i);
+    }
+  else
+    {
+      int j;
+      preallocated_sessions_per_worker = smm->preallocated_sessions /
+       (num_threads - 1);
 
-  clib_bihash_init_16_8 (&smm->v4_session_hash, "v4 session table",
-                        200000 /* $$$$ config parameter nbuckets */ ,
-                        (64 << 20) /*$$$ config parameter table size */ );
-  clib_bihash_init_48_8 (&smm->v6_session_hash, "v6 session table",
-                        200000 /* $$$$ config parameter nbuckets */ ,
-                        (64 << 20) /*$$$ config parameter table size */ );
+      for (j = 1; j < num_threads; j++)
+       {
+         for (i = 0; i < preallocated_sessions_per_worker; i++)
+           {
+             stream_session_t *ss __attribute__ ((unused));
+             pool_get_aligned (smm->sessions[j], ss, CLIB_CACHE_LINE_BYTES);
+           }
+         for (i = 0; i < preallocated_sessions_per_worker; i++)
+           pool_put_index (smm->sessions[j], i);
+       }
+    }
 
-  clib_bihash_init_16_8 (&smm->v4_half_open_hash, "v4 half-open table",
-                        200000 /* $$$$ config parameter nbuckets */ ,
-                        (64 << 20) /*$$$ config parameter table size */ );
-  clib_bihash_init_48_8 (&smm->v6_half_open_hash, "v6 half-open table",
-                        200000 /* $$$$ config parameter nbuckets */ ,
-                        (64 << 20) /*$$$ config parameter table size */ );
+  session_lookup_init ();
 
   smm->is_enabled = 1;
 
@@ -1174,15 +880,84 @@ clib_error_t *
 session_manager_main_init (vlib_main_t * vm)
 {
   session_manager_main_t *smm = &session_manager_main;
-
-  smm->vlib_main = vm;
-  smm->vnet_main = vnet_get_main ();
   smm->is_enabled = 0;
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (session_manager_main_init);
 
+static clib_error_t *
+session_config_fn (vlib_main_t * vm, unformat_input_t * input)
+{
+  session_manager_main_t *smm = &session_manager_main;
+  u32 nitems;
+  uword tmp;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "event-queue-length %d", &nitems))
+       {
+         if (nitems >= 2048)
+           smm->configured_event_queue_length = nitems;
+         else
+           clib_warning ("event queue length %d too small, ignored", nitems);
+       }
+      else if (unformat (input, "preallocated-sessions %d",
+                        &smm->preallocated_sessions))
+       ;
+      else if (unformat (input, "v4-session-table-buckets %d",
+                        &smm->configured_v4_session_table_buckets))
+       ;
+      else if (unformat (input, "v4-halfopen-table-buckets %d",
+                        &smm->configured_v4_halfopen_table_buckets))
+       ;
+      else if (unformat (input, "v6-session-table-buckets %d",
+                        &smm->configured_v6_session_table_buckets))
+       ;
+      else if (unformat (input, "v6-halfopen-table-buckets %d",
+                        &smm->configured_v6_halfopen_table_buckets))
+       ;
+      else if (unformat (input, "v4-session-table-memory %U",
+                        unformat_memory_size, &tmp))
+       {
+         if (tmp >= 0x100000000)
+           return clib_error_return (0, "memory size %llx (%lld) too large",
+                                     tmp, tmp);
+         smm->configured_v4_session_table_memory = tmp;
+       }
+      else if (unformat (input, "v4-halfopen-table-memory %U",
+                        unformat_memory_size, &tmp))
+       {
+         if (tmp >= 0x100000000)
+           return clib_error_return (0, "memory size %llx (%lld) too large",
+                                     tmp, tmp);
+         smm->configured_v4_halfopen_table_memory = tmp;
+       }
+      else if (unformat (input, "v6-session-table-memory %U",
+                        unformat_memory_size, &tmp))
+       {
+         if (tmp >= 0x100000000)
+           return clib_error_return (0, "memory size %llx (%lld) too large",
+                                     tmp, tmp);
+         smm->configured_v6_session_table_memory = tmp;
+       }
+      else if (unformat (input, "v6-halfopen-table-memory %U",
+                        unformat_memory_size, &tmp))
+       {
+         if (tmp >= 0x100000000)
+           return clib_error_return (0, "memory size %llx (%lld) too large",
+                                     tmp, tmp);
+         smm->configured_v6_halfopen_table_memory = tmp;
+       }
+      else
+       return clib_error_return (0, "unknown input `%U'",
+                                 format_unformat_error, input);
+    }
   return 0;
 }
 
-VLIB_INIT_FUNCTION (session_manager_main_init)
+VLIB_CONFIG_FUNCTION (session_config_fn, "session");
+
 /*
  * fd.io coding-style-patch-verification: ON
  *