2 * Copyright (c) 2016 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vnet/tcp/tcp.h>
17 #include <vnet/lisp-cp/packets.h>
20 vlib_node_registration_t tcp4_output_node;
21 vlib_node_registration_t tcp6_output_node;
23 typedef enum _tcp_output_next
26 TCP_OUTPUT_NEXT_IP_LOOKUP,
27 TCP_OUTPUT_NEXT_IP_REWRITE,
28 TCP_OUTPUT_NEXT_IP_ARP,
32 #define foreach_tcp4_output_next \
33 _ (DROP, "error-drop") \
34 _ (IP_LOOKUP, "ip4-lookup") \
35 _ (IP_REWRITE, "ip4-rewrite") \
38 #define foreach_tcp6_output_next \
39 _ (DROP, "error-drop") \
40 _ (IP_LOOKUP, "ip6-lookup") \
41 _ (IP_REWRITE, "ip6-rewrite") \
42 _ (IP_ARP, "ip6-discover-neighbor")
44 static char *tcp_error_strings[] = {
45 #define tcp_error(n,s) s,
46 #include <vnet/tcp/tcp_error.def>
52 tcp_header_t tcp_header;
53 tcp_connection_t tcp_connection;
59 format_tcp_tx_trace (u8 * s, va_list * args)
61 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
62 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
63 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
64 u32 indent = format_get_indent (s);
66 s = format (s, "%U\n%U%U",
67 format_tcp_header, &t->tcp_header, 128,
68 format_white_space, indent,
69 format_tcp_connection, &t->tcp_connection, 1);
75 tcp_window_compute_scale (u32 window)
78 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
84 * Update max segment size we're able to process.
86 * The value is constrained by our interface's MTU and IP options. It is
87 * also what we advertise to our peer.
90 tcp_update_rcv_mss (tcp_connection_t * tc)
92 /* TODO find our iface MTU */
93 tc->mss = dummy_mtu - sizeof (tcp_header_t);
97 * TCP's initial window
100 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
102 /* RFC 6928 recommends the value lower. However at the time our connections
103 * are initialized, fifos may not be allocated. Therefore, advertise the
104 * smallest possible unscaled window size and update once fifos are
105 * assigned to the session.
108 tcp_update_rcv_mss (tc);
109 TCP_IW_N_SEGMENTS * tc->mss;
111 return TCP_MIN_RX_FIFO_SIZE;
115 * Compute initial window and scale factor. As per RFC1323, window field in
116 * SYN and SYN-ACK segments is never scaled.
119 tcp_initial_window_to_advertise (tcp_connection_t * tc)
121 tcp_main_t *tm = &tcp_main;
124 /* Initial wnd for SYN. Fifos are not allocated yet.
125 * Use some predefined value. For SYN-ACK we still want the
126 * scale to be computed in the same way */
127 max_fifo = tm->max_rx_fifo ? tm->max_rx_fifo : TCP_MAX_RX_FIFO_SIZE;
129 tc->rcv_wscale = tcp_window_compute_scale (max_fifo);
130 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
132 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
136 tcp_update_rcv_wnd (tcp_connection_t * tc)
139 u32 available_space, max_fifo, wnd;
142 * Figure out how much space we have available
144 available_space = transport_max_rx_enqueue (&tc->connection);
145 max_fifo = transport_rx_fifo_size (&tc->connection);
147 ASSERT (tc->rcv_opts.mss < max_fifo);
148 if (available_space < tc->rcv_opts.mss && available_space < max_fifo >> 3)
152 * Use the above and what we know about what we've previously advertised
153 * to compute the new window
155 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
156 if (observed_wnd < 0)
159 /* Bad. Thou shalt not shrink */
160 if (available_space < observed_wnd)
163 TCP_EVT_DBG (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
167 wnd = available_space;
170 /* Make sure we have a multiple of rcv_wscale */
171 if (wnd && tc->rcv_wscale)
173 wnd &= ~(1 << tc->rcv_wscale);
175 wnd = 1 << tc->rcv_wscale;
178 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
182 * Compute and return window to advertise, scaled as per RFC1323
185 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
187 if (state < TCP_STATE_ESTABLISHED)
188 return tcp_initial_window_to_advertise (tc);
190 tcp_update_rcv_wnd (tc);
192 if (tc->rcv_wnd == 0)
194 tc->flags |= TCP_CONN_SENT_RCV_WND0;
198 tc->flags &= ~TCP_CONN_SENT_RCV_WND0;
201 return tc->rcv_wnd >> tc->rcv_wscale;
205 * Write TCP options to segment.
208 tcp_options_write (u8 * data, tcp_options_t * opts)
211 u32 buf, seq_len = 4;
213 if (tcp_opts_mss (opts))
215 *data++ = TCP_OPTION_MSS;
216 *data++ = TCP_OPTION_LEN_MSS;
217 buf = clib_host_to_net_u16 (opts->mss);
218 clib_memcpy (data, &buf, sizeof (opts->mss));
219 data += sizeof (opts->mss);
220 opts_len += TCP_OPTION_LEN_MSS;
223 if (tcp_opts_wscale (opts))
225 *data++ = TCP_OPTION_WINDOW_SCALE;
226 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
227 *data++ = opts->wscale;
228 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
231 if (tcp_opts_sack_permitted (opts))
233 *data++ = TCP_OPTION_SACK_PERMITTED;
234 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
235 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
238 if (tcp_opts_tstamp (opts))
240 *data++ = TCP_OPTION_TIMESTAMP;
241 *data++ = TCP_OPTION_LEN_TIMESTAMP;
242 buf = clib_host_to_net_u32 (opts->tsval);
243 clib_memcpy (data, &buf, sizeof (opts->tsval));
244 data += sizeof (opts->tsval);
245 buf = clib_host_to_net_u32 (opts->tsecr);
246 clib_memcpy (data, &buf, sizeof (opts->tsecr));
247 data += sizeof (opts->tsecr);
248 opts_len += TCP_OPTION_LEN_TIMESTAMP;
251 if (tcp_opts_sack (opts))
254 u32 n_sack_blocks = clib_min (vec_len (opts->sacks),
255 TCP_OPTS_MAX_SACK_BLOCKS);
257 if (n_sack_blocks != 0)
259 *data++ = TCP_OPTION_SACK_BLOCK;
260 *data++ = 2 + n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
261 for (i = 0; i < n_sack_blocks; i++)
263 buf = clib_host_to_net_u32 (opts->sacks[i].start);
264 clib_memcpy (data, &buf, seq_len);
266 buf = clib_host_to_net_u32 (opts->sacks[i].end);
267 clib_memcpy (data, &buf, seq_len);
270 opts_len += 2 + n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
274 /* Terminate TCP options */
277 *data++ = TCP_OPTION_EOL;
278 opts_len += TCP_OPTION_LEN_EOL;
281 /* Pad with zeroes to a u32 boundary */
284 *data++ = TCP_OPTION_NOOP;
285 opts_len += TCP_OPTION_LEN_NOOP;
291 tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale)
295 opts->flags |= TCP_OPTS_FLAG_MSS;
296 opts->mss = dummy_mtu; /*XXX discover that */
297 len += TCP_OPTION_LEN_MSS;
299 opts->flags |= TCP_OPTS_FLAG_WSCALE;
300 opts->wscale = wnd_scale;
301 len += TCP_OPTION_LEN_WINDOW_SCALE;
303 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
304 opts->tsval = tcp_time_now ();
306 len += TCP_OPTION_LEN_TIMESTAMP;
310 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
311 len += TCP_OPTION_LEN_SACK_PERMITTED;
314 /* Align to needed boundary */
315 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
320 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
324 opts->flags |= TCP_OPTS_FLAG_MSS;
326 len += TCP_OPTION_LEN_MSS;
328 if (tcp_opts_wscale (&tc->rcv_opts))
330 opts->flags |= TCP_OPTS_FLAG_WSCALE;
331 opts->wscale = tc->rcv_wscale;
332 len += TCP_OPTION_LEN_WINDOW_SCALE;
335 if (tcp_opts_tstamp (&tc->rcv_opts))
337 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
338 opts->tsval = tcp_time_now ();
339 opts->tsecr = tc->tsval_recent;
340 len += TCP_OPTION_LEN_TIMESTAMP;
343 if (tcp_opts_sack_permitted (&tc->rcv_opts))
345 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
346 len += TCP_OPTION_LEN_SACK_PERMITTED;
349 /* Align to needed boundary */
350 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
355 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
361 if (tcp_opts_tstamp (&tc->rcv_opts))
363 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
364 opts->tsval = tcp_time_now ();
365 opts->tsecr = tc->tsval_recent;
366 len += TCP_OPTION_LEN_TIMESTAMP;
368 if (tcp_opts_sack_permitted (&tc->rcv_opts))
370 if (vec_len (tc->snd_sacks))
372 opts->flags |= TCP_OPTS_FLAG_SACK;
373 opts->sacks = tc->snd_sacks;
374 opts->n_sack_blocks = clib_min (vec_len (tc->snd_sacks),
375 TCP_OPTS_MAX_SACK_BLOCKS);
376 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
380 /* Align to needed boundary */
381 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
386 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
391 case TCP_STATE_ESTABLISHED:
392 case TCP_STATE_FIN_WAIT_1:
393 case TCP_STATE_CLOSED:
394 case TCP_STATE_CLOSE_WAIT:
395 return tcp_make_established_options (tc, opts);
396 case TCP_STATE_SYN_RCVD:
397 return tcp_make_synack_options (tc, opts);
398 case TCP_STATE_SYN_SENT:
399 return tcp_make_syn_options (opts, tc->rcv_wscale);
401 clib_warning ("State not handled! %d", state);
407 * Update burst send vars
409 * - Updates snd_mss to reflect the effective segment size that we can send
410 * by taking into account all TCP options, including SACKs.
411 * - Cache 'on the wire' options for reuse
412 * - Updates receive window which can be reused for a burst.
414 * This should *only* be called when doing bursts
417 tcp_update_burst_snd_vars (tcp_connection_t * tc)
419 tcp_main_t *tm = &tcp_main;
421 /* Compute options to be used for connection. These may be reused when
422 * sending data or to compute the effective mss (snd_mss) */
423 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
424 TCP_STATE_ESTABLISHED);
426 /* XXX check if MTU has been updated */
427 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
428 ASSERT (tc->snd_mss > 0);
430 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
433 tcp_update_rcv_wnd (tc);
437 tcp_init_mss (tcp_connection_t * tc)
439 u16 default_min_mss = 536;
440 tcp_update_rcv_mss (tc);
442 /* TODO cache mss and consider PMTU discovery */
443 tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss);
445 if (tc->snd_mss < 45)
447 clib_warning ("snd mss is 0");
448 /* Assume that at least the min default mss works */
449 tc->snd_mss = default_min_mss;
450 tc->rcv_opts.mss = default_min_mss;
453 /* We should have enough space for 40 bytes of options */
454 ASSERT (tc->snd_mss > 45);
456 /* If we use timestamp option, account for it */
457 if (tcp_opts_tstamp (&tc->rcv_opts))
458 tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP;
462 tcp_alloc_tx_buffers (tcp_main_t * tm, u8 thread_index, u16 * n_bufs,
465 tcp_worker_ctx_t *ctx = &tm->wrk_ctx[thread_index];
466 vlib_main_t *vm = vlib_get_main ();
469 ASSERT (wanted > *n_bufs);
470 vec_validate_aligned (ctx->tx_buffers, wanted - 1, CLIB_CACHE_LINE_BYTES);
471 n_alloc = vlib_buffer_alloc (vm, &ctx->tx_buffers[*n_bufs],
474 _vec_len (ctx->tx_buffers) = *n_bufs;
479 tcp_get_free_buffer_index (tcp_main_t * tm, u32 * bidx)
481 u32 thread_index = vlib_get_thread_index ();
482 tcp_worker_ctx_t *ctx = &tm->wrk_ctx[thread_index];
483 u16 n_bufs = vec_len (ctx->tx_buffers);
485 TCP_DBG_BUFFER_ALLOC_MAYBE_FAIL (thread_index);
487 if (PREDICT_FALSE (!n_bufs))
489 if (!tcp_alloc_tx_buffers (tm, thread_index, &n_bufs, VLIB_FRAME_SIZE))
495 *bidx = ctx->tx_buffers[--n_bufs];
496 _vec_len (ctx->tx_buffers) = n_bufs;
501 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
503 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
504 vlib_buffer_free_one (vm, b->next_buffer);
505 /* Zero all flags but free list index and trace flag */
506 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
508 b->current_length = 0;
509 b->total_length_not_including_first_buffer = 0;
510 vnet_buffer (b)->tcp.flags = 0;
512 /* Leave enough space for headers */
513 return vlib_buffer_make_headroom (b, MAX_HDRS_LEN);
517 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
519 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
520 b->flags &= VLIB_BUFFER_NON_DEFAULT_FREELIST;
521 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
522 b->total_length_not_including_first_buffer = 0;
524 vnet_buffer (b)->tcp.flags = 0;
525 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
526 /* Leave enough space for headers */
527 return vlib_buffer_make_headroom (b, MAX_HDRS_LEN);
534 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
537 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
538 u8 tcp_opts_len, tcp_hdr_opts_len;
542 wnd = tcp_window_to_advertise (tc, state);
544 /* Make and write options */
545 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
546 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
548 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
549 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
551 tcp_options_write ((u8 *) (th + 1), snd_opts);
552 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
556 * Convert buffer to ACK
559 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
561 vlib_main_t *vm = vlib_get_main ();
563 tcp_reuse_buffer (vm, b);
564 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
565 TCP_EVT_DBG (TCP_EVT_ACK_SENT, tc);
566 vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_ACK;
567 tc->rcv_las = tc->rcv_nxt;
571 * Convert buffer to FIN-ACK
574 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
576 vlib_main_t *vm = vlib_get_main ();
579 tcp_reuse_buffer (vm, b);
581 flags = TCP_FLAG_FIN | TCP_FLAG_ACK;
582 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, flags);
584 /* Reset flags, make sure ack is sent */
585 vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK;
589 * Convert buffer to SYN
592 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
594 u8 tcp_hdr_opts_len, tcp_opts_len;
597 tcp_options_t snd_opts;
599 initial_wnd = tcp_initial_window_to_advertise (tc);
601 /* Make and write options */
602 clib_memset (&snd_opts, 0, sizeof (snd_opts));
603 tcp_opts_len = tcp_make_syn_options (&snd_opts, tc->rcv_wscale);
604 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
606 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
607 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
609 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
610 tcp_options_write ((u8 *) (th + 1), &snd_opts);
614 * Convert buffer to SYN-ACK
617 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
619 vlib_main_t *vm = vlib_get_main ();
620 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
621 u8 tcp_opts_len, tcp_hdr_opts_len;
625 clib_memset (snd_opts, 0, sizeof (*snd_opts));
626 tcp_reuse_buffer (vm, b);
628 initial_wnd = tcp_initial_window_to_advertise (tc);
629 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
630 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
632 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
633 tc->rcv_nxt, tcp_hdr_opts_len,
634 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
635 tcp_options_write ((u8 *) (th + 1), snd_opts);
637 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
638 vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_ACK;
640 /* Init retransmit timer. Use update instead of set because of
642 tcp_retransmit_timer_force_update (tc);
643 TCP_EVT_DBG (TCP_EVT_SYNACK_SENT, tc);
647 tcp_enqueue_to_ip_lookup_i (vlib_main_t * vm, vlib_buffer_t * b, u32 bi,
648 u8 is_ip4, u32 fib_index, u8 flush)
650 tcp_main_t *tm = vnet_get_tcp_main ();
651 u32 thread_index = vlib_get_thread_index ();
652 u32 *to_next, next_index;
655 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
658 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
659 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
661 /* Send to IP lookup */
662 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
663 tcp_trajectory_add_start (b, 1);
665 f = tm->wrk_ctx[thread_index].ip_lookup_tx_frames[!is_ip4];
668 f = vlib_get_frame_to_node (vm, next_index);
670 tm->wrk_ctx[thread_index].ip_lookup_tx_frames[!is_ip4] = f;
673 to_next = vlib_frame_vector_args (f);
674 to_next[f->n_vectors] = bi;
676 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
678 vlib_put_frame_to_node (vm, next_index, f);
679 tm->wrk_ctx[thread_index].ip_lookup_tx_frames[!is_ip4] = 0;
684 tcp_enqueue_to_ip_lookup_now (vlib_main_t * vm, vlib_buffer_t * b, u32 bi,
685 u8 is_ip4, u32 fib_index)
687 tcp_enqueue_to_ip_lookup_i (vm, b, bi, is_ip4, fib_index, 1);
691 tcp_enqueue_to_ip_lookup (vlib_main_t * vm, vlib_buffer_t * b, u32 bi,
692 u8 is_ip4, u32 fib_index)
694 tcp_enqueue_to_ip_lookup_i (vm, b, bi, is_ip4, fib_index, 0);
695 if (vm->thread_index == 0 && vlib_num_workers ())
696 session_flush_frames_main_thread (vm);
700 tcp_enqueue_to_output_i (vlib_main_t * vm, vlib_buffer_t * b, u32 bi,
703 tcp_main_t *tm = vnet_get_tcp_main ();
704 u32 thread_index = vlib_get_thread_index ();
705 u32 *to_next, next_index;
708 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
711 /* Decide where to send the packet */
712 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
713 tcp_trajectory_add_start (b, 2);
715 /* Get frame to v4/6 output node */
716 f = tm->wrk_ctx[thread_index].tx_frames[!is_ip4];
719 f = vlib_get_frame_to_node (vm, next_index);
721 tm->wrk_ctx[thread_index].tx_frames[!is_ip4] = f;
723 to_next = vlib_frame_vector_args (f);
724 to_next[f->n_vectors] = bi;
726 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
728 vlib_put_frame_to_node (vm, next_index, f);
729 tm->wrk_ctx[thread_index].tx_frames[!is_ip4] = 0;
734 tcp_enqueue_to_output (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, u8 is_ip4)
736 tcp_enqueue_to_output_i (vm, b, bi, is_ip4, 0);
740 tcp_enqueue_to_output_now (vlib_main_t * vm, vlib_buffer_t * b, u32 bi,
743 tcp_enqueue_to_output_i (vm, b, bi, is_ip4, 1);
747 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
748 tcp_state_t state, u8 thread_index, u8 is_ip4)
753 ip4_address_t src_ip40, dst_ip40;
754 ip6_address_t src_ip60, dst_ip60;
755 u16 src_port, dst_port;
760 /* Find IP and TCP headers */
761 th0 = tcp_buffer_hdr (b0);
763 /* Save src and dst ip */
766 ih4 = vlib_buffer_get_current (b0);
767 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
768 src_ip40.as_u32 = ih4->src_address.as_u32;
769 dst_ip40.as_u32 = ih4->dst_address.as_u32;
773 ih6 = vlib_buffer_get_current (b0);
774 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
775 clib_memcpy (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
776 clib_memcpy (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
779 src_port = th0->src_port;
780 dst_port = th0->dst_port;
782 /* Try to determine what/why we're actually resetting */
783 if (state == TCP_STATE_CLOSED)
788 tmp = clib_net_to_host_u32 (th0->seq_number);
790 /* Got a SYN for no listener. */
791 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
792 ack = clib_host_to_net_u32 (tmp + 1);
797 flags = TCP_FLAG_RST;
798 seq = th0->ack_number;
802 tcp_reuse_buffer (vm, b0);
803 tcp_trajectory_add_start (b0, 4);
804 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
805 sizeof (tcp_header_t), flags, 0);
809 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
811 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
816 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
818 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
826 * Send reset without reusing existing buffer
828 * It extracts connection info out of original packet
831 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt, u8 is_ip4)
834 u32 bi, sw_if_index, fib_index;
835 tcp_main_t *tm = vnet_get_tcp_main ();
836 vlib_main_t *vm = vlib_get_main ();
837 u8 tcp_hdr_len, flags = 0;
838 tcp_header_t *th, *pkt_th;
840 ip4_header_t *ih4, *pkt_ih4;
841 ip6_header_t *ih6, *pkt_ih6;
842 fib_protocol_t fib_proto;
844 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
847 b = vlib_get_buffer (vm, bi);
848 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
849 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
850 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
851 tcp_init_buffer (vm, b);
853 /* Make and write options */
854 tcp_hdr_len = sizeof (tcp_header_t);
858 pkt_ih4 = vlib_buffer_get_current (pkt);
859 pkt_th = ip4_next_header (pkt_ih4);
863 pkt_ih6 = vlib_buffer_get_current (pkt);
864 pkt_th = ip6_next_header (pkt_ih6);
867 if (tcp_ack (pkt_th))
869 flags = TCP_FLAG_RST;
870 seq = pkt_th->ack_number;
871 ack = (tc && tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
875 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
877 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
880 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
881 seq, ack, tcp_hdr_len, flags, 0);
883 /* Swap src and dst ip */
886 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
887 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
888 &pkt_ih4->src_address, IP_PROTOCOL_TCP, 1);
889 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
894 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
896 ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
897 &pkt_ih6->src_address, IP_PROTOCOL_TCP);
898 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
902 tcp_enqueue_to_ip_lookup_now (vm, b, bi, is_ip4, fib_index);
903 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
907 * Build and set reset packet for connection
910 tcp_send_reset (tcp_connection_t * tc)
912 vlib_main_t *vm = vlib_get_main ();
913 tcp_main_t *tm = vnet_get_tcp_main ();
917 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
920 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
922 b = vlib_get_buffer (vm, bi);
923 tcp_init_buffer (vm, b);
925 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
926 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
927 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
928 flags = TCP_FLAG_RST;
929 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
930 tc->rcv_nxt, tcp_hdr_opts_len, flags,
932 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
933 ASSERT (opts_write_len == tc->snd_opts_len);
934 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
938 ih4 = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip.ip4,
939 &tc->c_rmt_ip.ip4, IP_PROTOCOL_TCP, 0);
940 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
946 ih6 = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip.ip6,
947 &tc->c_rmt_ip.ip6, IP_PROTOCOL_TCP);
948 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
951 tcp_enqueue_to_ip_lookup_now (vm, b, bi, tc->c_is_ip4, tc->c_fib_index);
952 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
956 tcp_push_ip_hdr (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b)
958 tcp_header_t *th = vlib_buffer_get_current (b);
959 vlib_main_t *vm = vlib_get_main ();
963 ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
964 &tc->c_rmt_ip4, IP_PROTOCOL_TCP, 1);
965 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
972 ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
973 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
974 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
982 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
983 * The packet is not forwarded through tcpx_output to avoid doing lookups
984 * in the half_open pool.
987 tcp_send_syn (tcp_connection_t * tc)
991 tcp_main_t *tm = vnet_get_tcp_main ();
992 vlib_main_t *vm = vlib_get_main ();
995 * Setup retransmit and establish timers before requesting buffer
996 * such that we can return if we've ran out.
998 tcp_timer_set (tc, TCP_TIMER_ESTABLISH, TCP_ESTABLISH_TIME);
999 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1000 tc->rto * TCP_TO_TIMER_TICK);
1002 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1005 b = vlib_get_buffer (vm, bi);
1006 tcp_init_buffer (vm, b);
1007 tcp_make_syn (tc, b);
1009 /* Measure RTT with this */
1010 tc->rtt_ts = tcp_time_now ();
1011 tc->rtt_seq = tc->snd_nxt;
1014 tcp_push_ip_hdr (tm, tc, b);
1015 tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4, tc->c_fib_index);
1016 TCP_EVT_DBG (TCP_EVT_SYN_SENT, tc);
1020 * Flush tx frame populated by retransmits and timer pops
1023 tcp_flush_frame_to_output (vlib_main_t * vm, u8 thread_index, u8 is_ip4)
1025 if (tcp_main.wrk_ctx[thread_index].tx_frames[!is_ip4])
1028 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
1029 vlib_put_frame_to_node (vm, next_index,
1031 wrk_ctx[thread_index].tx_frames[!is_ip4]);
1032 tcp_main.wrk_ctx[thread_index].tx_frames[!is_ip4] = 0;
1037 * Flush ip lookup tx frames populated by timer pops
1040 tcp_flush_frame_to_ip_lookup (vlib_main_t * vm, u8 thread_index, u8 is_ip4)
1042 if (tcp_main.wrk_ctx[thread_index].ip_lookup_tx_frames[!is_ip4])
1045 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
1046 vlib_put_frame_to_node (vm, next_index,
1048 wrk_ctx[thread_index].ip_lookup_tx_frames
1050 tcp_main.wrk_ctx[thread_index].ip_lookup_tx_frames[!is_ip4] = 0;
1055 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
1058 tcp_flush_frames_to_output (u8 thread_index)
1060 vlib_main_t *vm = vlib_get_main ();
1061 tcp_flush_frame_to_output (vm, thread_index, 1);
1062 tcp_flush_frame_to_output (vm, thread_index, 0);
1063 tcp_flush_frame_to_ip_lookup (vm, thread_index, 1);
1064 tcp_flush_frame_to_ip_lookup (vm, thread_index, 0);
1071 tcp_send_fin (tcp_connection_t * tc)
1073 tcp_main_t *tm = vnet_get_tcp_main ();
1074 vlib_main_t *vm = vlib_get_main ();
1079 fin_snt = tc->flags & TCP_CONN_FINSNT;
1081 tc->snd_nxt = tc->snd_una;
1083 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1085 /* Out of buffers so program fin retransmit ASAP */
1086 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1090 tcp_retransmit_timer_force_update (tc);
1091 b = vlib_get_buffer (vm, bi);
1092 tcp_init_buffer (vm, b);
1093 tcp_make_fin (tc, b);
1094 tcp_enqueue_to_output_now (vm, b, bi, tc->c_is_ip4);
1095 TCP_EVT_DBG (TCP_EVT_FIN_SENT, tc);
1100 tc->flags |= TCP_CONN_FINSNT;
1101 tc->flags &= ~TCP_CONN_FINPNDG;
1102 /* Account for the FIN */
1103 tc->snd_una_max += 1;
1104 tc->snd_nxt = tc->snd_una_max;
1108 tc->snd_nxt = tc->snd_una_max;
1113 tcp_make_state_flags (tcp_connection_t * tc, tcp_state_t next_state)
1117 case TCP_STATE_ESTABLISHED:
1118 case TCP_STATE_CLOSE_WAIT:
1119 return TCP_FLAG_ACK;
1120 case TCP_STATE_SYN_RCVD:
1121 return TCP_FLAG_SYN | TCP_FLAG_ACK;
1122 case TCP_STATE_SYN_SENT:
1123 return TCP_FLAG_SYN;
1124 case TCP_STATE_LAST_ACK:
1125 case TCP_STATE_FIN_WAIT_1:
1126 if (tc->snd_nxt + 1 < tc->snd_una_max)
1127 return TCP_FLAG_ACK;
1129 return TCP_FLAG_FIN;
1131 clib_warning ("Shouldn't be here!");
1137 * Push TCP header and update connection variables
1140 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b,
1141 tcp_state_t next_state, u8 compute_opts, u8 maybe_burst)
1143 u32 advertise_wnd, data_len;
1144 u8 tcp_hdr_opts_len, flags;
1145 tcp_main_t *tm = &tcp_main;
1148 data_len = b->current_length;
1149 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1150 data_len += b->total_length_not_including_first_buffer;
1152 vnet_buffer (b)->tcp.flags = 0;
1153 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
1156 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1158 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
1161 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1163 advertise_wnd = tcp_window_to_advertise (tc, next_state);
1165 flags = tcp_make_state_flags (tc, next_state);
1167 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
1168 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1173 clib_memcpy ((u8 *) (th + 1),
1174 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1179 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1180 ASSERT (len == tc->snd_opts_len);
1184 * Update connection variables
1187 tc->snd_nxt += data_len;
1188 tc->rcv_las = tc->rcv_nxt;
1190 TCP_EVT_DBG (TCP_EVT_PKTIZE, tc);
1194 tcp_push_header (tcp_connection_t * tc, vlib_buffer_t * b)
1196 tcp_push_hdr_i (tc, b, TCP_STATE_ESTABLISHED, /* compute opts */ 0,
1198 tc->snd_una_max = tc->snd_nxt;
1199 ASSERT (seq_leq (tc->snd_una_max, tc->snd_una + tc->snd_wnd
1200 + tcp_fastrecovery_sent_1_smss (tc) * tc->snd_mss));
1201 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1202 /* If not tracking an ACK, start tracking */
1203 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1205 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1206 tc->rtt_seq = tc->snd_nxt;
1208 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1210 tcp_retransmit_timer_set (tc);
1213 tcp_trajectory_add_start (b, 3);
1218 tcp_send_ack (tcp_connection_t * tc)
1220 tcp_main_t *tm = vnet_get_tcp_main ();
1221 vlib_main_t *vm = vlib_get_main ();
1227 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1229 b = vlib_get_buffer (vm, bi);
1230 tcp_init_buffer (vm, b);
1232 /* Fill in the ACK */
1233 tcp_make_ack (tc, b);
1234 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1238 * Delayed ack timer handler
1240 * Sends delayed ACK when timer expires
1243 tcp_timer_delack_handler (u32 index)
1245 u32 thread_index = vlib_get_thread_index ();
1246 tcp_connection_t *tc;
1248 tc = tcp_connection_get (index, thread_index);
1249 tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID;
1254 * Build a retransmit segment
1256 * @return the number of bytes in the segment or 0 if there's nothing to
1260 tcp_prepare_retransmit_segment (tcp_connection_t * tc, u32 offset,
1261 u32 max_deq_bytes, vlib_buffer_t ** b)
1263 tcp_main_t *tm = vnet_get_tcp_main ();
1264 vlib_main_t *vm = vlib_get_main ();
1266 u32 start, bi, available_bytes, seg_size;
1269 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1270 ASSERT (max_deq_bytes != 0);
1273 * Make sure we can retransmit something
1275 available_bytes = session_tx_fifo_max_dequeue (&tc->connection);
1276 ASSERT (available_bytes >= offset);
1277 available_bytes -= offset;
1278 if (!available_bytes)
1280 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1281 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1283 /* Start is beyond snd_congestion */
1284 start = tc->snd_una + offset;
1285 if (seq_geq (start, tc->snd_congestion))
1288 /* Don't overshoot snd_congestion */
1289 if (seq_gt (start + max_deq_bytes, tc->snd_congestion))
1291 max_deq_bytes = tc->snd_congestion - start;
1292 if (max_deq_bytes == 0)
1296 seg_size = max_deq_bytes + MAX_HDRS_LEN;
1301 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1304 * Allocate and fill in buffer(s)
1307 /* Easy case, buffer size greater than mss */
1308 if (PREDICT_TRUE (seg_size <= tm->bytes_per_buffer))
1310 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1312 *b = vlib_get_buffer (vm, bi);
1313 data = tcp_init_buffer (vm, *b);
1314 n_bytes = stream_session_peek_bytes (&tc->connection, data, offset,
1316 ASSERT (n_bytes == max_deq_bytes);
1317 b[0]->current_length = n_bytes;
1318 tcp_push_hdr_i (tc, *b, tc->state, /* compute opts */ 0, /* burst */ 0);
1319 if (seq_gt (tc->snd_nxt, tc->snd_una_max))
1320 tc->snd_una_max = tc->snd_nxt;
1322 /* Split mss into multiple buffers */
1325 u32 chain_bi = ~0, n_bufs_per_seg;
1326 u32 thread_index = vlib_get_thread_index ();
1327 u16 n_peeked, len_to_deq, available_bufs;
1328 vlib_buffer_t *chain_b, *prev_b;
1331 /* Make sure we have enough buffers */
1332 n_bufs_per_seg = ceil ((double) seg_size / tm->bytes_per_buffer);
1333 available_bufs = vec_len (tm->wrk_ctx[thread_index].tx_buffers);
1334 if (n_bufs_per_seg > available_bufs)
1336 tcp_alloc_tx_buffers (tm, thread_index, &available_bufs,
1339 if (n_bufs_per_seg > available_bufs)
1346 tcp_get_free_buffer_index (tm, &bi);
1347 ASSERT (bi != (u32) ~ 0);
1348 *b = vlib_get_buffer (vm, bi);
1349 data = tcp_init_buffer (vm, *b);
1350 n_bytes = stream_session_peek_bytes (&tc->connection, data, offset,
1351 tm->bytes_per_buffer -
1353 b[0]->current_length = n_bytes;
1354 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1355 b[0]->total_length_not_including_first_buffer = 0;
1356 max_deq_bytes -= n_bytes;
1359 for (i = 1; i < n_bufs_per_seg; i++)
1362 len_to_deq = clib_min (max_deq_bytes, tm->bytes_per_buffer);
1363 tcp_get_free_buffer_index (tm, &chain_bi);
1364 ASSERT (chain_bi != (u32) ~ 0);
1365 chain_b = vlib_get_buffer (vm, chain_bi);
1366 chain_b->current_data = 0;
1367 data = vlib_buffer_get_current (chain_b);
1368 n_peeked = stream_session_peek_bytes (&tc->connection, data,
1369 offset + n_bytes, len_to_deq);
1370 ASSERT (n_peeked == len_to_deq);
1371 n_bytes += n_peeked;
1372 chain_b->current_length = n_peeked;
1373 chain_b->next_buffer = 0;
1375 /* update previous buffer */
1376 prev_b->next_buffer = chain_bi;
1377 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1379 max_deq_bytes -= n_peeked;
1380 b[0]->total_length_not_including_first_buffer += n_peeked;
1383 tcp_push_hdr_i (tc, *b, tc->state, /* compute opts */ 0, /* burst */ 0);
1384 if (seq_gt (tc->snd_nxt, tc->snd_una_max))
1385 tc->snd_una_max = tc->snd_nxt;
1388 ASSERT (n_bytes > 0);
1389 ASSERT (((*b)->current_data + (*b)->current_length) <=
1390 tm->bytes_per_buffer);
1392 if (tcp_in_fastrecovery (tc))
1393 tc->snd_rxt_bytes += n_bytes;
1396 TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1401 * Reset congestion control, switch cwnd to loss window and try again.
1404 tcp_rxt_timeout_cc (tcp_connection_t * tc)
1406 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 6);
1407 tc->prev_ssthresh = tc->ssthresh;
1408 tc->prev_cwnd = tc->cwnd;
1410 /* Cleanly recover cc (also clears up fast retransmit) */
1411 if (tcp_in_fastrecovery (tc))
1413 /* TODO be less aggressive about this */
1414 scoreboard_clear (&tc->sack_sb);
1415 tcp_cc_fastrecovery_exit (tc);
1418 /* Start again from the beginning */
1419 tc->cc_algo->congestion (tc);
1420 tc->cwnd = tcp_loss_wnd (tc);
1421 tc->snd_congestion = tc->snd_una_max;
1423 tc->cwnd_acc_bytes = 0;
1425 tcp_recovery_on (tc);
1429 tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
1431 tcp_main_t *tm = vnet_get_tcp_main ();
1432 vlib_main_t *vm = vlib_get_main ();
1433 u32 thread_index = vlib_get_thread_index ();
1434 tcp_connection_t *tc;
1435 vlib_buffer_t *b = 0;
1440 tc = tcp_half_open_connection_get (index);
1441 /* Note: the connection may have transitioned to ESTABLISHED... */
1442 if (PREDICT_FALSE (tc == 0))
1444 tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1448 tc = tcp_connection_get (index, thread_index);
1449 /* Note: the connection may have been closed and pool_put */
1450 if (PREDICT_FALSE (tc == 0))
1452 tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
1455 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 1);
1457 if (tc->state >= TCP_STATE_ESTABLISHED)
1459 /* Lost FIN, retransmit and return */
1460 if (tcp_is_lost_fin (tc))
1464 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1468 /* Shouldn't be here. This condition is tricky because it has to take
1469 * into account boff > 0 due to persist timeout. */
1470 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_una_max)
1471 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1472 && !tcp_flight_size (tc)))
1474 ASSERT (!tcp_in_recovery (tc));
1479 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1480 * to persist timer timeout */
1481 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1484 tcp_update_rto (tc);
1487 /* Increment RTO backoff (also equal to number of retries) and go back
1488 * to first un-acked byte */
1491 /* First retransmit timeout */
1492 if (tc->rto_boff == 1)
1493 tcp_rxt_timeout_cc (tc);
1495 scoreboard_clear (&tc->sack_sb);
1497 /* If we've sent beyond snd_congestion, update it */
1498 if (seq_gt (tc->snd_una_max, tc->snd_congestion))
1499 tc->snd_congestion = tc->snd_una_max;
1501 tc->snd_una_max = tc->snd_nxt = tc->snd_una;
1502 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1504 /* Send one segment. Note that n_bytes may be zero due to buffer
1506 n_bytes = tcp_prepare_retransmit_segment (tc, 0, tc->snd_mss, &b);
1510 tcp_retransmit_timer_force_update (tc);
1514 bi = vlib_get_buffer_index (vm, b);
1516 /* For first retransmit, record timestamp (Eifel detection RFC3522) */
1517 if (tc->rto_boff == 1)
1518 tc->snd_rxt_ts = tcp_time_now ();
1520 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1521 tcp_retransmit_timer_force_update (tc);
1523 /* Retransmit for SYN */
1524 else if (tc->state == TCP_STATE_SYN_SENT)
1526 /* Half-open connection actually moved to established but we were
1527 * waiting for syn retransmit to pop to call cleanup from the right
1529 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1531 if (tcp_half_open_connection_cleanup (tc))
1533 clib_warning ("could not remove half-open connection");
1539 /* Try without increasing RTO a number of times. If this fails,
1540 * start growing RTO exponentially */
1542 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1543 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1545 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1546 tc->rto * TCP_TO_TIMER_TICK);
1548 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1551 b = vlib_get_buffer (vm, bi);
1552 tcp_init_buffer (vm, b);
1553 tcp_make_syn (tc, b);
1556 TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 0);
1558 /* This goes straight to ipx_lookup. Retransmit timer set already */
1559 tcp_push_ip_hdr (tm, tc, b);
1560 tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4, tc->c_fib_index);
1562 /* Retransmit SYN-ACK */
1563 else if (tc->state == TCP_STATE_SYN_RCVD)
1566 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1567 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1570 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1572 tcp_retransmit_timer_force_update (tc);
1576 b = vlib_get_buffer (vm, bi);
1577 tcp_init_buffer (vm, b);
1578 tcp_make_synack (tc, b);
1579 TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 1);
1581 /* Retransmit timer already updated, just enqueue to output */
1582 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1586 ASSERT (tc->state == TCP_STATE_CLOSED);
1592 tcp_timer_retransmit_handler (u32 index)
1594 tcp_timer_retransmit_handler_i (index, 0);
1598 tcp_timer_retransmit_syn_handler (u32 index)
1600 tcp_timer_retransmit_handler_i (index, 1);
1604 * Got 0 snd_wnd from peer, try to do something about it.
1608 tcp_timer_persist_handler (u32 index)
1610 tcp_main_t *tm = vnet_get_tcp_main ();
1611 vlib_main_t *vm = vlib_get_main ();
1612 u32 thread_index = vlib_get_thread_index ();
1613 tcp_connection_t *tc;
1615 u32 bi, max_snd_bytes, available_bytes, offset;
1619 tc = tcp_connection_get_if_valid (index, thread_index);
1624 /* Make sure timer handle is set to invalid */
1625 tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID;
1627 /* Problem already solved or worse */
1628 if (tc->state == TCP_STATE_CLOSED || tc->state > TCP_STATE_ESTABLISHED
1629 || tc->snd_wnd > tc->snd_mss || tcp_in_recovery (tc))
1632 available_bytes = session_tx_fifo_max_dequeue (&tc->connection);
1633 offset = tc->snd_una_max - tc->snd_una;
1635 /* Reprogram persist if no new bytes available to send. We may have data
1637 if (!available_bytes)
1639 tcp_persist_timer_set (tc);
1643 if (available_bytes <= offset)
1645 ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
1649 /* Increment RTO backoff */
1651 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1654 * Try to force the first unsent segment (or buffer)
1656 if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi)))
1658 tcp_persist_timer_set (tc);
1661 b = vlib_get_buffer (vm, bi);
1662 data = tcp_init_buffer (vm, b);
1664 tcp_validate_txf_size (tc, offset);
1665 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1666 max_snd_bytes = clib_min (tc->snd_mss, tm->bytes_per_buffer - MAX_HDRS_LEN);
1667 n_bytes = stream_session_peek_bytes (&tc->connection, data, offset,
1669 b->current_length = n_bytes;
1670 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1671 || tc->snd_nxt == tc->snd_una_max
1672 || tc->rto_boff > 1));
1674 tcp_push_hdr_i (tc, b, tc->state, /* compute opts */ 0, /* burst */ 0);
1675 tc->snd_una_max = tc->snd_nxt;
1676 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1677 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1679 /* Just sent new data, enable retransmit */
1680 tcp_retransmit_timer_update (tc);
1684 * Retransmit first unacked segment
1687 tcp_retransmit_first_unacked (tcp_connection_t * tc)
1689 vlib_main_t *vm = vlib_get_main ();
1691 u32 bi, old_snd_nxt, n_bytes;
1693 old_snd_nxt = tc->snd_nxt;
1694 tc->snd_nxt = tc->snd_una;
1696 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1698 n_bytes = tcp_prepare_retransmit_segment (tc, 0, tc->snd_mss, &b);
1702 bi = vlib_get_buffer_index (vm, b);
1703 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1704 tc->snd_nxt = old_snd_nxt;
1710 * Do fast retransmit with SACKs
1713 tcp_fast_retransmit_sack (tcp_connection_t * tc, u32 burst_size)
1715 vlib_main_t *vm = vlib_get_main ();
1716 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1717 vlib_buffer_t *b = 0;
1718 sack_scoreboard_hole_t *hole;
1719 sack_scoreboard_t *sb;
1720 u32 bi, old_snd_nxt;
1722 u8 snd_limited = 0, can_rescue = 0;
1724 ASSERT (tcp_in_fastrecovery (tc));
1726 old_snd_nxt = tc->snd_nxt;
1728 snd_space = tcp_available_cc_snd_space (tc);
1729 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1731 if (snd_space < tc->snd_mss)
1733 tcp_program_fastretransmit (tc);
1737 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
1738 while (snd_space > 0 && n_segs < burst_size)
1740 hole = scoreboard_next_rxt_hole (sb, hole,
1741 tcp_fastrecovery_sent_1_smss (tc),
1742 &can_rescue, &snd_limited);
1745 if (!can_rescue || !(seq_lt (sb->rescue_rxt, tc->snd_una)
1746 || seq_gt (sb->rescue_rxt,
1747 tc->snd_congestion)))
1749 if (tcp_fastrecovery_first (tc))
1752 /* We tend to lose the first segment. Try re-resending
1753 * it but only once and after we've tried everything */
1754 hole = scoreboard_first_hole (sb);
1755 if (hole && hole->start == tc->snd_una)
1757 tcp_retransmit_first_unacked (tc);
1758 tcp_fastrecovery_first_on (tc);
1764 /* If rescue rxt undefined or less than snd_una then one segment of
1765 * up to SMSS octets that MUST include the highest outstanding
1766 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1767 * RecoveryPoint. HighRxt MUST NOT be updated.
1769 max_bytes = clib_min (tc->snd_mss,
1770 tc->snd_congestion - tc->snd_una);
1771 max_bytes = clib_min (max_bytes, snd_space);
1772 offset = tc->snd_congestion - tc->snd_una - max_bytes;
1773 sb->rescue_rxt = tc->snd_congestion;
1774 tc->snd_nxt = tc->snd_una + offset;
1775 n_written = tcp_prepare_retransmit_segment (tc, offset, max_bytes,
1780 bi = vlib_get_buffer_index (vm, b);
1781 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1786 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1787 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1790 offset = sb->high_rxt - tc->snd_una;
1791 tc->snd_nxt = sb->high_rxt;
1792 n_written = tcp_prepare_retransmit_segment (tc, offset, max_bytes, &b);
1794 /* Nothing left to retransmit */
1798 bi = vlib_get_buffer_index (vm, b);
1799 sb->high_rxt += n_written;
1800 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1801 ASSERT (n_written <= snd_space);
1802 snd_space -= n_written;
1807 tcp_program_fastretransmit (tc);
1810 /* If window allows, send 1 SMSS of new data */
1811 tc->snd_nxt = old_snd_nxt;
1816 * Fast retransmit without SACK info
1819 tcp_fast_retransmit_no_sack (tcp_connection_t * tc, u32 burst_size)
1821 vlib_main_t *vm = vlib_get_main ();
1822 u32 n_written = 0, offset = 0, bi, old_snd_nxt;
1823 int snd_space, n_segs = 0;
1826 ASSERT (tcp_in_fastrecovery (tc));
1827 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
1829 /* Start resending from first un-acked segment */
1830 old_snd_nxt = tc->snd_nxt;
1831 tc->snd_nxt = tc->snd_una;
1832 snd_space = tcp_available_cc_snd_space (tc);
1834 while (snd_space > 0 && n_segs < burst_size)
1836 offset += n_written;
1837 n_written = tcp_prepare_retransmit_segment (tc, offset, snd_space, &b);
1839 /* Nothing left to retransmit */
1843 bi = vlib_get_buffer_index (vm, b);
1844 tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
1845 snd_space -= n_written;
1849 /* More data to resend */
1850 if (seq_lt (tc->snd_nxt, tc->snd_congestion))
1851 tcp_program_fastretransmit (tc);
1853 /* Restore snd_nxt. If window allows, send 1 SMSS of new data */
1854 tc->snd_nxt = old_snd_nxt;
1860 * Do fast retransmit
1863 tcp_fast_retransmit (tcp_connection_t * tc, u32 burst_size)
1865 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1866 return tcp_fast_retransmit_sack (tc, burst_size);
1868 return tcp_fast_retransmit_no_sack (tc, burst_size);
1872 tcp_session_has_ooo_data (tcp_connection_t * tc)
1874 stream_session_t *s = session_get (tc->c_s_index, tc->c_thread_index);
1875 return svm_fifo_has_ooo_data (s->server_rx_fifo);
1879 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
1880 u16 * next0, u32 * error0)
1882 ip_adjacency_t *adj;
1885 /* Not thread safe but as long as the connection exists the adj should
1887 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
1889 if (ai == ADJ_INDEX_INVALID)
1891 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
1892 *next0 = TCP_OUTPUT_NEXT_DROP;
1893 *error0 = TCP_ERROR_LINK_LOCAL_RW;
1898 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
1899 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
1900 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
1901 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
1904 *next0 = TCP_OUTPUT_NEXT_DROP;
1905 *error0 = TCP_ERROR_LINK_LOCAL_RW;
1907 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
1911 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1912 u32 * to_next, u32 n_bufs)
1914 u32 n_trace = vlib_get_trace_count (vm, node);
1915 tcp_connection_t *tc;
1921 for (i = 0; i < clib_min (n_trace, n_bufs); i++)
1923 b = vlib_get_buffer (vm, to_next[i]);
1924 th = vlib_buffer_get_current (b);
1925 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
1927 t = vlib_add_trace (vm, node, b, sizeof (*t));
1928 clib_memcpy (&t->tcp_header, th, sizeof (t->tcp_header));
1929 clib_memcpy (&t->tcp_connection, tc, sizeof (t->tcp_connection));
1934 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
1935 tcp_connection_t * tc0, u8 is_ip4)
1937 tcp_header_t *th0 = 0;
1939 th0 = vlib_buffer_get_current (b0);
1940 TCP_EVT_DBG (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length);
1943 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
1944 IP_PROTOCOL_TCP, 1);
1945 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
1946 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
1952 ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6,
1953 &tc0->c_rmt_ip6, IP_PROTOCOL_TCP);
1954 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
1955 vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data;
1956 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
1962 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
1963 u32 * error0, u16 * next0, u8 is_ip4)
1966 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
1968 *error0 = TCP_ERROR_INVALID_CONNECTION;
1969 *next0 = TCP_OUTPUT_NEXT_DROP;
1973 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
1974 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
1978 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
1979 tcp_output_handle_link_local (tc0, b0, next0, error0);
1982 /* Filter out DUPACKs if there are no OOO segments left */
1983 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.flags & TCP_BUF_FLAG_DUPACK))
1985 /* N.B. Should not filter burst of dupacks. Two issues:
1986 * 1) dupacks open cwnd on remote peer when congested
1987 * 2) acks leaving should have the latest rcv_wnd since the
1988 * burst may have eaten up all of it, so only the old ones
1989 * could be filtered.
1991 if (!tcp_session_has_ooo_data (tc0))
1993 *error0 = TCP_ERROR_FILTERED_DUPACKS;
1994 *next0 = TCP_OUTPUT_NEXT_DROP;
1999 /* Stop DELACK timer and fix flags */
2000 tc0->flags &= ~(TCP_CONN_SNDACK);
2001 if (!TCP_ALWAYS_ACK)
2002 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
2006 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2007 vlib_frame_t * frame, int is_ip4)
2009 u32 n_left_from, *from, thread_index = vm->thread_index;
2010 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2011 u16 nexts[VLIB_FRAME_SIZE], *next;
2013 from = vlib_frame_vector_args (frame);
2014 n_left_from = frame->n_vectors;
2015 tcp_set_time_now (thread_index);
2017 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2018 tcp46_output_trace_frame (vm, node, from, n_left_from);
2020 vlib_get_buffers (vm, from, bufs, n_left_from);
2024 while (n_left_from >= 4)
2026 u32 error0 = TCP_ERROR_PKTS_SENT, error1 = TCP_ERROR_PKTS_SENT;
2027 tcp_connection_t *tc0, *tc1;
2030 vlib_prefetch_buffer_header (b[2], STORE);
2031 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2033 vlib_prefetch_buffer_header (b[3], STORE);
2034 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2037 next[0] = next[1] = TCP_OUTPUT_NEXT_IP_LOOKUP;
2039 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2041 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2044 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2045 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2047 tcp_output_handle_packet (tc0, b[0], &error0, &next[0], is_ip4);
2048 tcp_output_handle_packet (tc1, b[1], &error1, &next[1], is_ip4);
2054 while (n_left_from > 0)
2056 u32 error0 = TCP_ERROR_PKTS_SENT;
2057 tcp_connection_t *tc0;
2059 if (n_left_from > 1)
2061 vlib_prefetch_buffer_header (b[1], STORE);
2062 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2065 next[0] = TCP_OUTPUT_NEXT_IP_LOOKUP;
2066 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2069 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2070 tcp_output_handle_packet (tc0, b[0], &error0, &next[0], is_ip4);
2077 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2078 return frame->n_vectors;
2082 tcp4_output (vlib_main_t * vm, vlib_node_runtime_t * node,
2083 vlib_frame_t * from_frame)
2085 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2089 tcp6_output (vlib_main_t * vm, vlib_node_runtime_t * node,
2090 vlib_frame_t * from_frame)
2092 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2096 VLIB_REGISTER_NODE (tcp4_output_node) =
2098 .function = tcp4_output,.name = "tcp4-output",
2099 /* Takes a vector of packets. */
2100 .vector_size = sizeof (u32),
2101 .n_errors = TCP_N_ERROR,
2102 .error_strings = tcp_error_strings,
2103 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2105 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2106 foreach_tcp4_output_next
2109 .format_buffer = format_tcp_header,
2110 .format_trace = format_tcp_tx_trace,
2114 VLIB_NODE_FUNCTION_MULTIARCH (tcp4_output_node, tcp4_output);
2117 VLIB_REGISTER_NODE (tcp6_output_node) =
2119 .function = tcp6_output,
2120 .name = "tcp6-output",
2121 /* Takes a vector of packets. */
2122 .vector_size = sizeof (u32),
2123 .n_errors = TCP_N_ERROR,
2124 .error_strings = tcp_error_strings,
2125 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2127 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2128 foreach_tcp6_output_next
2131 .format_buffer = format_tcp_header,
2132 .format_trace = format_tcp_tx_trace,
2136 VLIB_NODE_FUNCTION_MULTIARCH (tcp6_output_node, tcp6_output);
2138 typedef enum _tcp_reset_next
2140 TCP_RESET_NEXT_DROP,
2141 TCP_RESET_NEXT_IP_LOOKUP,
2145 #define foreach_tcp4_reset_next \
2146 _(DROP, "error-drop") \
2147 _(IP_LOOKUP, "ip4-lookup")
2149 #define foreach_tcp6_reset_next \
2150 _(DROP, "error-drop") \
2151 _(IP_LOOKUP, "ip6-lookup")
2154 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2155 vlib_frame_t * from_frame, u8 is_ip4)
2157 u32 n_left_from, next_index, *from, *to_next;
2158 u32 my_thread_index = vm->thread_index;
2160 from = vlib_frame_vector_args (from_frame);
2161 n_left_from = from_frame->n_vectors;
2163 next_index = node->cached_next_index;
2165 while (n_left_from > 0)
2169 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2171 while (n_left_from > 0 && n_left_to_next > 0)
2177 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2184 n_left_to_next -= 1;
2186 b0 = vlib_get_buffer (vm, bi0);
2188 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2189 my_thread_index, is_ip4))
2191 error0 = TCP_ERROR_LOOKUP_DROPS;
2192 next0 = TCP_RESET_NEXT_DROP;
2196 /* Prepare to send to IP lookup */
2197 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2198 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2201 b0->error = node->errors[error0];
2202 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2203 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2205 th0 = vlib_buffer_get_current (b0);
2207 th0 = ip4_next_header ((ip4_header_t *) th0);
2209 th0 = ip6_next_header ((ip6_header_t *) th0);
2210 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2211 clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2214 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2215 n_left_to_next, bi0, next0);
2217 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2219 return from_frame->n_vectors;
2223 tcp4_send_reset (vlib_main_t * vm, vlib_node_runtime_t * node,
2224 vlib_frame_t * from_frame)
2226 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2230 tcp6_send_reset (vlib_main_t * vm, vlib_node_runtime_t * node,
2231 vlib_frame_t * from_frame)
2233 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2237 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2238 .function = tcp4_send_reset,
2239 .name = "tcp4-reset",
2240 .vector_size = sizeof (u32),
2241 .n_errors = TCP_N_ERROR,
2242 .error_strings = tcp_error_strings,
2243 .n_next_nodes = TCP_RESET_N_NEXT,
2245 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2246 foreach_tcp4_reset_next
2249 .format_trace = format_tcp_tx_trace,
2253 VLIB_NODE_FUNCTION_MULTIARCH (tcp4_reset_node, tcp4_send_reset);
2256 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2257 .function = tcp6_send_reset,
2258 .name = "tcp6-reset",
2259 .vector_size = sizeof (u32),
2260 .n_errors = TCP_N_ERROR,
2261 .error_strings = tcp_error_strings,
2262 .n_next_nodes = TCP_RESET_N_NEXT,
2264 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2265 foreach_tcp6_reset_next
2268 .format_trace = format_tcp_tx_trace,
2272 VLIB_NODE_FUNCTION_MULTIARCH (tcp6_reset_node, tcp6_send_reset);
2275 * fd.io coding-style-patch-verification: ON
2278 * eval: (c-set-style "gnu")