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path: root/src/vnet/session/application_local.c
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.. _vpp18.07:

###############################
Features for Release VPP 18.07
###############################

This section lists those features that became available in VPP Release 18.07: 

Infrastructure
+++++++++++++++

* DPDK 18.02.1

   - Complete rework of the dpdk-input node
   - Display rx/tx burst function name in "show hardware detail"
   - Improve buffer alloc performance
      + This is ~50% improvement in buffer alloc performance. For a 256 buffer allocation, it was ~10 clocks/buffer, now is < 5 clocks.
   - Add per-numa page allocation info to 'show memory'
   - Vectorized bihash_{48,40,24,16}_8 key compare
      + bihash_48_8 case:
         * Scalar code: 6 clocks
         * SSE4.2 code: 3 clocks
         * AVX2 code: 2.27 clocks
         * AVX512 code: 1.5 clocks
   - Pollable Stats
      + Stats are now available to a client in a shared memory segment and in the form of a directory, allowing very high performance polling of stats without directly querying VPP.

VNET & Plugins
+++++++++++++++

* IGMP improvements
   - Enable/Disable an interface for IGMP
   - improve logging
   - refactor common code
   - no orphaned timers
   - IGMP state changes in main thread only
   - Large groups split over multiple state-change reports
   - SSM range configuration API.
   - more tests
* IP: vectorized IP checksum
* VXLAN : HW offload RX flow
* Rework kube-proxy into LB plugin and add NATA66
* NAT:
   - Code refactor
   - Syslog
   - Multiple outside interfaces
   - Endpoint dependent filtering and mapping
* ACL:
   - Tuple Merge algorithm cleanup and integration
   - Processing pipeline optimizations
   - Refactoring
* Experimental AVF driver


Host stack
+++++++++++

* Session: performance improvements, add support for connectionless transports, datagram reception and transmission
* TCP: congestion control improvements and overall fixes
* UDP: datagram mode
* TLS async support

Known issues
---------------

For the full list of issues please refer to fd.io `JIRA <https://jira.fd.io/>`_.

Issues fixed
--------------

For the full list of fixed issues please refer to:

* fd.io `JIRA <https://jira.fd.io/>`_
* git `commit log <https://git.fd.io/vpp/log/?h=stable/1807>`_
472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597
/*
 * 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 <vnet/session/application_local.h>
#include <vnet/session/session.h>

static ct_connection_t *connections;

static void
ct_enable_disable_main_pre_input_node (u8 is_add)
{
  u32 n_conns;

  if (!vlib_num_workers ())
    return;

  n_conns = pool_elts (connections);
  if (n_conns > 2)
    return;

  if (n_conns > 0 && is_add)
    vlib_node_set_state (vlib_get_main (),
			 session_queue_pre_input_node.index,
			 VLIB_NODE_STATE_POLLING);
  else if (n_conns == 0)
    vlib_node_set_state (vlib_get_main (),
			 session_queue_pre_input_node.index,
			 VLIB_NODE_STATE_DISABLED);
}

static ct_connection_t *
ct_connection_alloc (void)
{
  ct_connection_t *ct;

  pool_get_zero (connections, ct);
  ct->c_c_index = ct - connections;
  ct->c_thread_index = 0;
  ct->client_wrk = ~0;
  ct->server_wrk = ~0;
  return ct;
}

static ct_connection_t *
ct_connection_get (u32 ct_index)
{
  if (pool_is_free_index (connections, ct_index))
    return 0;
  return pool_elt_at_index (connections, ct_index);
}

static void
ct_connection_free (ct_connection_t * ct)
{
  if (CLIB_DEBUG)
    memset (ct, 0xfc, sizeof (*ct));
  pool_put (connections, ct);
}

session_t *
ct_session_get_peer (session_t * s)
{
  ct_connection_t *ct, *peer_ct;
  ct = ct_connection_get (s->connection_index);
  peer_ct = ct_connection_get (ct->peer_index);
  return session_get (peer_ct->c_s_index, 0);
}

void
ct_session_endpoint (session_t * ll, session_endpoint_t * sep)
{
  ct_connection_t *ct;
  ct = (ct_connection_t *) session_get_transport (ll);
  sep->transport_proto = ct->actual_tp;
  sep->port = ct->c_lcl_port;
  sep->is_ip4 = ct->c_is_ip4;
}

int
ct_session_connect_notify (session_t * ss)
{
  ct_connection_t *sct, *cct;
  app_worker_t *client_wrk;
  segment_manager_t *sm;
  fifo_segment_t *seg;
  u64 segment_handle;
  int is_fail = 0;
  session_t *cs;
  u32 ss_index;

  ss_index = ss->session_index;
  sct = (ct_connection_t *) session_get_transport (ss);
  client_wrk = app_worker_get (sct->client_wrk);

  sm = segment_manager_get (ss->rx_fifo->segment_manager);
  seg = segment_manager_get_segment_w_lock (sm, ss->rx_fifo->segment_index);
  segment_handle = segment_manager_segment_handle (sm, seg);

  if (app_worker_add_segment_notify (client_wrk, segment_handle))
    {
      clib_warning ("failed to notify client %u of new segment",
		    sct->client_wrk);
      segment_manager_segment_reader_unlock (sm);
      session_close (ss);
      is_fail = 1;
    }
  else
    {
      segment_manager_segment_reader_unlock (sm);
    }

  /* Alloc client session */
  cct = ct_connection_get (sct->peer_index);

  cs = session_alloc (0);
  ss = session_get (ss_index, 0);
  cs->session_type = ss->session_type;
  cs->connection_index = sct->c_c_index;
  cs->listener_handle = SESSION_INVALID_HANDLE;
  cs->session_state = SESSION_STATE_CONNECTING;
  cs->app_wrk_index = client_wrk->wrk_index;
  cs->connection_index = cct->c_c_index;

  cct->c_s_index = cs->session_index;
  cct->client_rx_fifo = ss->tx_fifo;
  cct->client_tx_fifo = ss->rx_fifo;

  cct->client_rx_fifo->refcnt++;
  cct->client_tx_fifo->refcnt++;

  /* This will allocate fifos for the session. They won't be used for
   * exchanging data but they will be used to close the connection if
   * the segment manager/worker is freed */
  if (app_worker_init_connected (client_wrk, cs))
    {
      session_close (ss);
      return -1;
    }

  if (app_worker_connect_notify (client_wrk, is_fail ? 0 : cs,
				 sct->client_opaque))
    {
      session_close (ss);
      return -1;
    }

  cs = session_get (cct->c_s_index, 0);
  cs->session_state = SESSION_STATE_READY;

  return 0;
}

static int
ct_init_local_session (app_worker_t * client_wrk, app_worker_t * server_wrk,
		       ct_connection_t * ct, session_t * ls, session_t * ll)
{
  u32 round_rx_fifo_sz, round_tx_fifo_sz, sm_index, seg_size;
  segment_manager_props_t *props;
  application_t *server;
  segment_manager_t *sm;
  u32 margin = 16 << 10;
  fifo_segment_t *seg;
  u64 segment_handle;
  int seg_index, rv;

  server = application_get (server_wrk->app_index);

  props = application_segment_manager_properties (server);
  round_rx_fifo_sz = 1 << max_log2 (props->rx_fifo_size);
  round_tx_fifo_sz = 1 << max_log2 (props->tx_fifo_size);
  seg_size = round_rx_fifo_sz + round_tx_fifo_sz + margin;

  sm = app_worker_get_listen_segment_manager (server_wrk, ll);
  seg_index = segment_manager_add_segment (sm, seg_size);
  if (seg_index < 0)
    {
      clib_warning ("failed to add new cut-through segment");
      return seg_index;
    }
  seg = segment_manager_get_segment_w_lock (sm, seg_index);

  rv = segment_manager_try_alloc_fifos (seg, ls->thread_index,
					props->rx_fifo_size,
					props->tx_fifo_size, &ls->rx_fifo,
					&ls->tx_fifo);
  if (rv)
    {
      clib_warning ("failed to add fifos in cut-through segment");
      segment_manager_segment_reader_unlock (sm);
      goto failed;
    }

  sm_index = segment_manager_index (sm);
  ls->rx_fifo->master_session_index = ls->session_index;
  ls->tx_fifo->master_session_index = ls->session_index;
  ls->rx_fifo->segment_manager = sm_index;
  ls->tx_fifo->segment_manager = sm_index;
  ls->rx_fifo->segment_index = seg_index;
  ls->tx_fifo->segment_index = seg_index;

  segment_handle = segment_manager_segment_handle (sm, seg);
  if ((rv = app_worker_add_segment_notify (server_wrk, segment_handle)))
    {
      clib_warning ("failed to notify server of new segment");
      segment_manager_segment_reader_unlock (sm);
      goto failed;
    }
  segment_manager_segment_reader_unlock (sm);
  ct->segment_handle = segment_handle;

  return 0;

failed:
  segment_manager_del_segment (sm, seg);
  return rv;
}

static int
ct_connect (app_worker_t * client_wrk, session_t * ll,
	    session_endpoint_cfg_t * sep)
{
  u32 cct_index, ll_index, ll_ct_index;
  ct_connection_t *sct, *cct, *ll_ct;
  app_worker_t *server_wrk;
  session_t *ss;

  ll_index = ll->session_index;
  ll_ct_index = ll->connection_index;

  cct = ct_connection_alloc ();
  cct_index = cct->c_c_index;
  sct = ct_connection_alloc ();
  ll_ct = ct_connection_get (ll_ct_index);

  /*
   * Alloc and init client transport
   */
  cct = ct_connection_get (cct_index);
  cct->c_thread_index = 0;
  cct->c_rmt_port = sep->port;
  cct->c_lcl_port = 0;
  cct->c_is_ip4 = sep->is_ip4;
  clib_memcpy (&cct->c_rmt_ip, &sep->ip, sizeof (sep->ip));
  cct->actual_tp = ll_ct->actual_tp;
  cct->is_client = 1;

  /*
   * Init server transport
   */
  sct->c_thread_index = 0;
  sct->c_rmt_port = 0;
  sct->c_lcl_port = ll_ct->c_lcl_port;
  sct->c_is_ip4 = sep->is_ip4;
  clib_memcpy (&sct->c_lcl_ip, &ll_ct->c_lcl_ip, sizeof (ll_ct->c_lcl_ip));
  sct->client_wrk = client_wrk->wrk_index;
  sct->c_proto = TRANSPORT_PROTO_NONE;
  sct->client_opaque = sep->opaque;
  sct->actual_tp = ll_ct->actual_tp;

  sct->peer_index = cct->c_c_index;
  cct->peer_index = sct->c_c_index;

  /*
   * Accept server session. Client session is created only after
   * server confirms accept.
   */
  ss = session_alloc (0);
  ll = listen_session_get (ll_index);
  ss->session_type = session_type_from_proto_and_ip (TRANSPORT_PROTO_NONE,
						     sct->c_is_ip4);
  ss->connection_index = sct->c_c_index;
  ss->listener_handle = listen_session_get_handle (ll);
  ss->session_state = SESSION_STATE_CREATED;

  server_wrk = application_listener_select_worker (ll);
  ss->app_wrk_index = server_wrk->wrk_index;

  sct->c_s_index = ss->session_index;
  sct->server_wrk = ss->app_wrk_index;

  if (ct_init_local_session (client_wrk, server_wrk, sct, ss, ll))
    {
      clib_warning ("failed");
      ct_connection_free (sct);
      session_free (ss);
      return -1;
    }

  ss->session_state = SESSION_STATE_ACCEPTING;
  if (app_worker_accept_notify (server_wrk, ss))
    {
      clib_warning ("failed");
      ct_connection_free (sct);
      session_free_w_fifos (ss);
      return -1;
    }

  cct->segment_handle = sct->segment_handle;
  ct_enable_disable_main_pre_input_node (1 /* is_add */ );
  return 0;
}

static u32
ct_start_listen (u32 app_listener_index, transport_endpoint_t * tep)
{
  session_endpoint_cfg_t *sep;
  ct_connection_t *ct;

  sep = (session_endpoint_cfg_t *) tep;
  ct = ct_connection_alloc ();
  ct->server_wrk = sep->app_wrk_index;
  ct->c_is_ip4 = sep->is_ip4;
  clib_memcpy (&ct->c_lcl_ip, &sep->ip, sizeof (sep->ip));
  ct->c_lcl_port = sep->port;
  ct->actual_tp = sep->transport_proto;
  ct_enable_disable_main_pre_input_node (1 /* is_add */ );
  return ct->c_c_index;
}

static u32
ct_stop_listen (u32 ct_index)
{
  ct_connection_t *ct;
  ct = ct_connection_get (ct_index);
  ct_connection_free (ct);
  ct_enable_disable_main_pre_input_node (0 /* is_add */ );
  return 0;
}

static transport_connection_t *
ct_listener_get (u32 ct_index)
{
  return (transport_connection_t *) ct_connection_get (ct_index);
}

static int
ct_session_connect (transport_endpoint_cfg_t * tep)
{
  session_endpoint_cfg_t *sep_ext;
  session_endpoint_t *sep;
  app_worker_t *app_wrk;
  session_handle_t lh;
  application_t *app;
  app_listener_t *al;
  u32 table_index;
  session_t *ll;
  u8 fib_proto;

  sep_ext = (session_endpoint_cfg_t *) tep;
  sep = (session_endpoint_t *) tep;
  app_wrk = app_worker_get (sep_ext->app_wrk_index);
  app = application_get (app_wrk->app_index);

  sep->transport_proto = sep_ext->original_tp;
  table_index = application_local_session_table (app);
  lh = session_lookup_local_endpoint (table_index, sep);
  if (lh == SESSION_DROP_HANDLE)
    return VNET_API_ERROR_APP_CONNECT_FILTERED;

  if (lh == SESSION_INVALID_HANDLE)
    goto global_scope;

  ll = listen_session_get_from_handle (lh);
  al = app_listener_get_w_session (ll);

  /*
   * Break loop if rule in local table points to connecting app. This
   * can happen if client is a generic proxy. Route connect through
   * global table instead.
   */
  if (al->app_index == app->app_index)
    goto global_scope;

  return ct_connect (app_wrk, ll, sep_ext);

  /*
   * If nothing found, check the global scope for locally attached
   * destinations. Make sure first that we're allowed to.
   */

global_scope:
  if (session_endpoint_is_local (sep))
    return VNET_API_ERROR_SESSION_CONNECT;

  if (!application_has_global_scope (app))
    return VNET_API_ERROR_APP_CONNECT_SCOPE;

  fib_proto = session_endpoint_fib_proto (sep);
  table_index = session_lookup_get_index_for_fib (fib_proto, sep->fib_index);
  ll = session_lookup_listener_wildcard (table_index, sep);

  if (ll)
    return ct_connect (app_wrk, ll, sep_ext);

  /* Failed to connect but no error */
  return 1;
}

static void
ct_session_close (u32 ct_index, u32 thread_index)
{
  ct_connection_t *ct, *peer_ct;
  app_worker_t *app_wrk;
  session_t *s;

  ct = ct_connection_get (ct_index);
  peer_ct = ct_connection_get (ct->peer_index);
  if (peer_ct)
    {
      peer_ct->peer_index = ~0;
      session_transport_closing_notify (&peer_ct->connection);
    }

  s = session_get (ct->c_s_index, 0);
  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (app_wrk)
    app_worker_del_segment_notify (app_wrk, ct->segment_handle);
  session_free_w_fifos (s);
  if (ct->is_client)
    segment_manager_dealloc_fifos (ct->client_rx_fifo, ct->client_tx_fifo);

  ct_connection_free (ct);
  ct_enable_disable_main_pre_input_node (0 /* is_add */ );
}

static transport_connection_t *
ct_session_get (u32 ct_index, u32 thread_index)
{
  return (transport_connection_t *) ct_connection_get (ct_index);
}

static u8 *
format_ct_connection_id (u8 * s, va_list * args)
{
  ct_connection_t *ct = va_arg (*args, ct_connection_t *);
  if (!ct)
    return s;
  if (ct->c_is_ip4)
    {
      s = format (s, "[%d:%d][CT:%U] %U:%d->%U:%d", ct->c_thread_index,
		  ct->c_s_index, format_transport_proto_short, ct->actual_tp,
		  format_ip4_address, &ct->c_lcl_ip4,
		  clib_net_to_host_u16 (ct->c_lcl_port), format_ip4_address,
		  &ct->c_rmt_ip4, clib_net_to_host_u16 (ct->c_rmt_port));
    }
  else
    {
      s = format (s, "[%d:%d][CT:%U] %U:%d->%U:%d", ct->c_thread_index,
		  ct->c_s_index, format_transport_proto_short, ct->actual_tp,
		  format_ip6_address, &ct->c_lcl_ip6,
		  clib_net_to_host_u16 (ct->c_lcl_port), format_ip6_address,
		  &ct->c_rmt_ip6, clib_net_to_host_u16 (ct->c_rmt_port));
    }

  return s;
}

static int
ct_custom_tx (void *session, u32 max_burst_size)
{
  session_t *s = (session_t *) session;
  if (session_has_transport (s))
    return 0;
  return ct_session_tx (s);
}

static int
ct_app_rx_evt (transport_connection_t * tc)
{
  ct_connection_t *ct = (ct_connection_t *) tc, *peer_ct;
  session_t *ps;

  peer_ct = ct_connection_get (ct->peer_index);
  if (!peer_ct)
    return -1;
  ps = session_get (peer_ct->c_s_index, peer_ct->c_thread_index);
  return session_dequeue_notify (ps);
}

static u8 *
format_ct_listener (u8 * s, va_list * args)
{
  u32 tc_index = va_arg (*args, u32);
  u32 __clib_unused thread_index = va_arg (*args, u32);
  u32 __clib_unused verbose = va_arg (*args, u32);
  ct_connection_t *ct = ct_connection_get (tc_index);
  s = format (s, "%-50U", format_ct_connection_id, ct);
  if (verbose)
    s = format (s, "%-15s", "LISTEN");
  return s;
}

static u8 *
format_ct_connection (u8 * s, va_list * args)
{
  ct_connection_t *ct = va_arg (*args, ct_connection_t *);
  u32 verbose = va_arg (*args, u32);

  if (!ct)
    return s;
  s = format (s, "%-50U", format_ct_connection_id, ct);
  if (verbose)
    {
      s = format (s, "%-15s", "ESTABLISHED");
      if (verbose > 1)
	{
	  s = format (s, "\n");
	}
    }
  return s;
}

static u8 *
format_ct_session (u8 * s, va_list * args)
{
  u32 ct_index = va_arg (*args, u32);
  u32 __clib_unused thread_index = va_arg (*args, u32);
  u32 verbose = va_arg (*args, u32);
  ct_connection_t *ct;

  ct = ct_connection_get (ct_index);
  if (!ct)
    {
      s = format (s, "empty\n");
      return s;
    }

  s = format (s, "%U", format_ct_connection, ct, verbose);
  return s;
}

/* *INDENT-OFF* */
static const transport_proto_vft_t cut_thru_proto = {
  .start_listen = ct_start_listen,
  .stop_listen = ct_stop_listen,
  .get_listener = ct_listener_get,
  .connect = ct_session_connect,
  .close = ct_session_close,
  .get_connection = ct_session_get,
  .custom_tx = ct_custom_tx,
  .app_rx_evt = ct_app_rx_evt,
  .format_listener = format_ct_listener,
  .format_connection = format_ct_session,
  .transport_options = {
    .tx_type = TRANSPORT_TX_INTERNAL,
    .service_type = TRANSPORT_SERVICE_APP,
  },
};
/* *INDENT-ON* */

int
ct_session_tx (session_t * s)
{
  ct_connection_t *ct, *peer_ct;
  session_t *peer_s;

  ct = (ct_connection_t *) session_get_transport (s);
  peer_ct = ct_connection_get (ct->peer_index);
  if (!peer_ct)
    return -1;
  peer_s = session_get (peer_ct->c_s_index, 0);
  if (peer_s->session_state >= SESSION_STATE_TRANSPORT_CLOSING)
    return 0;
  return session_enqueue_notify (peer_s);
}

static clib_error_t *
ct_transport_init (vlib_main_t * vm)
{
  transport_register_protocol (TRANSPORT_PROTO_NONE, &cut_thru_proto,
			       FIB_PROTOCOL_IP4, ~0);
  transport_register_protocol (TRANSPORT_PROTO_NONE, &cut_thru_proto,
			       FIB_PROTOCOL_IP6, ~0);
  return 0;
}

VLIB_INIT_FUNCTION (ct_transport_init);

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */