2 * Copyright (c) 2016-2019 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>
19 typedef enum _tcp_output_next
22 TCP_OUTPUT_NEXT_IP_LOOKUP,
23 TCP_OUTPUT_NEXT_IP_REWRITE,
24 TCP_OUTPUT_NEXT_IP_ARP,
28 #define foreach_tcp4_output_next \
29 _ (DROP, "error-drop") \
30 _ (IP_LOOKUP, "ip4-lookup") \
31 _ (IP_REWRITE, "ip4-rewrite") \
34 #define foreach_tcp6_output_next \
35 _ (DROP, "error-drop") \
36 _ (IP_LOOKUP, "ip6-lookup") \
37 _ (IP_REWRITE, "ip6-rewrite") \
38 _ (IP_ARP, "ip6-discover-neighbor")
40 static char *tcp_error_strings[] = {
41 #define tcp_error(n,s) s,
42 #include <vnet/tcp/tcp_error.def>
48 tcp_header_t tcp_header;
49 tcp_connection_t tcp_connection;
53 format_tcp_tx_trace (u8 * s, va_list * args)
55 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
56 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
57 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
58 u32 indent = format_get_indent (s);
60 s = format (s, "%U\n%U%U",
61 format_tcp_header, &t->tcp_header, 128,
62 format_white_space, indent,
63 format_tcp_connection, &t->tcp_connection, 1);
68 #ifndef CLIB_MARCH_VARIANT
70 tcp_window_compute_scale (u32 window)
73 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
79 * TCP's initial window
82 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
84 /* RFC 6928 recommends the value lower. However at the time our connections
85 * are initialized, fifos may not be allocated. Therefore, advertise the
86 * smallest possible unscaled window size and update once fifos are
87 * assigned to the session.
90 tcp_update_rcv_mss (tc);
91 TCP_IW_N_SEGMENTS * tc->mss;
93 return tcp_cfg.min_rx_fifo;
97 * Compute initial window and scale factor. As per RFC1323, window field in
98 * SYN and SYN-ACK segments is never scaled.
101 tcp_initial_window_to_advertise (tcp_connection_t * tc)
103 /* Compute rcv wscale only if peer advertised support for it */
104 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
105 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
107 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
109 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
113 tcp_update_rcv_wnd (tcp_connection_t * tc)
115 u32 available_space, wnd;
118 ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection));
121 * Figure out how much space we have available
123 available_space = transport_max_rx_enqueue (&tc->connection);
124 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
131 * Use the above and what we know about what we've previously advertised
132 * to compute the new window
134 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
136 /* Bad. Thou shalt not shrink */
137 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
139 wnd = clib_max (observed_wnd, 0);
140 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
144 wnd = available_space;
147 /* Make sure we have a multiple of rcv_wscale */
148 if (wnd && tc->rcv_wscale)
150 wnd &= ~((1 << tc->rcv_wscale) - 1);
152 wnd = 1 << tc->rcv_wscale;
155 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
159 * Compute and return window to advertise, scaled as per RFC1323
162 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
164 if (state < TCP_STATE_ESTABLISHED)
165 return tcp_initial_window_to_advertise (tc);
167 tcp_update_rcv_wnd (tc);
168 return tc->rcv_wnd >> tc->rcv_wscale;
172 * Write TCP options to segment.
175 tcp_options_write (u8 * data, tcp_options_t * opts)
178 u32 buf, seq_len = 4;
180 if (tcp_opts_mss (opts))
182 *data++ = TCP_OPTION_MSS;
183 *data++ = TCP_OPTION_LEN_MSS;
184 buf = clib_host_to_net_u16 (opts->mss);
185 clib_memcpy_fast (data, &buf, sizeof (opts->mss));
186 data += sizeof (opts->mss);
187 opts_len += TCP_OPTION_LEN_MSS;
190 if (tcp_opts_wscale (opts))
192 *data++ = TCP_OPTION_WINDOW_SCALE;
193 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
194 *data++ = opts->wscale;
195 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
198 if (tcp_opts_sack_permitted (opts))
200 *data++ = TCP_OPTION_SACK_PERMITTED;
201 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
202 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
205 if (tcp_opts_tstamp (opts))
207 *data++ = TCP_OPTION_TIMESTAMP;
208 *data++ = TCP_OPTION_LEN_TIMESTAMP;
209 buf = clib_host_to_net_u32 (opts->tsval);
210 clib_memcpy_fast (data, &buf, sizeof (opts->tsval));
211 data += sizeof (opts->tsval);
212 buf = clib_host_to_net_u32 (opts->tsecr);
213 clib_memcpy_fast (data, &buf, sizeof (opts->tsecr));
214 data += sizeof (opts->tsecr);
215 opts_len += TCP_OPTION_LEN_TIMESTAMP;
218 if (tcp_opts_sack (opts))
222 if (opts->n_sack_blocks != 0)
224 *data++ = TCP_OPTION_SACK_BLOCK;
225 *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
226 for (i = 0; i < opts->n_sack_blocks; i++)
228 buf = clib_host_to_net_u32 (opts->sacks[i].start);
229 clib_memcpy_fast (data, &buf, seq_len);
231 buf = clib_host_to_net_u32 (opts->sacks[i].end);
232 clib_memcpy_fast (data, &buf, seq_len);
235 opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
239 /* Terminate TCP options */
242 *data++ = TCP_OPTION_EOL;
243 opts_len += TCP_OPTION_LEN_EOL;
246 /* Pad with zeroes to a u32 boundary */
249 *data++ = TCP_OPTION_NOOP;
250 opts_len += TCP_OPTION_LEN_NOOP;
256 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
260 opts->flags |= TCP_OPTS_FLAG_MSS;
262 len += TCP_OPTION_LEN_MSS;
264 opts->flags |= TCP_OPTS_FLAG_WSCALE;
265 opts->wscale = tc->rcv_wscale;
266 len += TCP_OPTION_LEN_WINDOW_SCALE;
268 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
269 opts->tsval = tcp_time_now ();
271 len += TCP_OPTION_LEN_TIMESTAMP;
275 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
276 len += TCP_OPTION_LEN_SACK_PERMITTED;
279 /* Align to needed boundary */
280 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
285 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
289 opts->flags |= TCP_OPTS_FLAG_MSS;
291 len += TCP_OPTION_LEN_MSS;
293 if (tcp_opts_wscale (&tc->rcv_opts))
295 opts->flags |= TCP_OPTS_FLAG_WSCALE;
296 opts->wscale = tc->rcv_wscale;
297 len += TCP_OPTION_LEN_WINDOW_SCALE;
300 if (tcp_opts_tstamp (&tc->rcv_opts))
302 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
303 opts->tsval = tcp_time_now ();
304 opts->tsecr = tc->tsval_recent;
305 len += TCP_OPTION_LEN_TIMESTAMP;
308 if (tcp_opts_sack_permitted (&tc->rcv_opts))
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_established_options (tcp_connection_t * tc, tcp_options_t * opts)
326 if (tcp_opts_tstamp (&tc->rcv_opts))
328 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
329 opts->tsval = tcp_tstamp (tc);
330 opts->tsecr = tc->tsval_recent;
331 len += TCP_OPTION_LEN_TIMESTAMP;
333 if (tcp_opts_sack_permitted (&tc->rcv_opts))
335 if (vec_len (tc->snd_sacks))
337 opts->flags |= TCP_OPTS_FLAG_SACK;
338 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
339 tc->snd_sack_pos = 0;
340 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
341 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
342 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
343 TCP_OPTS_MAX_SACK_BLOCKS);
344 tc->snd_sack_pos += opts->n_sack_blocks;
345 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
349 /* Align to needed boundary */
350 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
355 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
360 case TCP_STATE_ESTABLISHED:
361 case TCP_STATE_CLOSE_WAIT:
362 case TCP_STATE_FIN_WAIT_1:
363 case TCP_STATE_LAST_ACK:
364 case TCP_STATE_CLOSING:
365 case TCP_STATE_FIN_WAIT_2:
366 case TCP_STATE_TIME_WAIT:
367 case TCP_STATE_CLOSED:
368 return tcp_make_established_options (tc, opts);
369 case TCP_STATE_SYN_RCVD:
370 return tcp_make_synack_options (tc, opts);
371 case TCP_STATE_SYN_SENT:
372 return tcp_make_syn_options (tc, opts);
374 clib_warning ("State not handled! %d", state);
380 * Update burst send vars
382 * - Updates snd_mss to reflect the effective segment size that we can send
383 * by taking into account all TCP options, including SACKs.
384 * - Cache 'on the wire' options for reuse
385 * - Updates receive window which can be reused for a burst.
387 * This should *only* be called when doing bursts
390 tcp_update_burst_snd_vars (tcp_connection_t * tc)
392 tcp_main_t *tm = &tcp_main;
394 /* Compute options to be used for connection. These may be reused when
395 * sending data or to compute the effective mss (snd_mss) */
396 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
397 TCP_STATE_ESTABLISHED);
399 /* XXX check if MTU has been updated */
400 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
401 ASSERT (tc->snd_mss > 0);
403 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
406 tcp_update_rcv_wnd (tc);
408 if (tc->flags & TCP_CONN_RATE_SAMPLE)
409 tc->flags |= TCP_CONN_TRACK_BURST;
411 if (tc->snd_una == tc->snd_nxt)
412 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
415 #endif /* CLIB_MARCH_VARIANT */
418 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
420 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
421 vlib_buffer_free_one (vm, b->next_buffer);
422 /* Zero all flags but free list index and trace flag */
423 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
425 b->current_length = 0;
426 b->total_length_not_including_first_buffer = 0;
427 vnet_buffer (b)->tcp.flags = 0;
429 /* Leave enough space for headers */
430 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
433 #ifndef CLIB_MARCH_VARIANT
435 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
437 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
438 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
439 b->total_length_not_including_first_buffer = 0;
441 vnet_buffer (b)->tcp.flags = 0;
442 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
443 /* Leave enough space for headers */
444 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
448 /* Compute TCP checksum in software when offloading is disabled for a connection */
450 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
451 ip46_address_t * src, ip46_address_t * dst)
454 u16 payload_length_host_byte_order;
457 /* Initialize checksum with ip header. */
458 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
459 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
460 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
462 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
464 sum0 = ip_csum_with_carry
465 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
466 sum0 = ip_csum_with_carry
467 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
470 return ip_calculate_l4_checksum (vm, p0, sum0,
471 payload_length_host_byte_order, NULL, 0,
476 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
477 ip46_address_t * src, ip46_address_t * dst)
480 u32 payload_length_host_byte_order;
482 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
484 clib_host_to_net_u32 (payload_length_host_byte_order +
485 (IP_PROTOCOL_TCP << 16));
487 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
488 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
490 return ip_calculate_l4_checksum (vm, p0, sum0,
491 payload_length_host_byte_order, NULL, 0,
496 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
499 if (PREDICT_FALSE (tc->flags & TCP_CONN_NO_CSUM_OFFLOAD))
501 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
502 vlib_main_t *vm = wrk->vm;
505 checksum = ip4_tcp_compute_checksum_custom
506 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
508 checksum = ip6_tcp_compute_checksum_custom
509 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
513 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
523 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
526 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
527 u8 tcp_opts_len, tcp_hdr_opts_len;
531 wnd = tcp_window_to_advertise (tc, state);
533 /* Make and write options */
534 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
535 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
537 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
538 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
540 tcp_options_write ((u8 *) (th + 1), snd_opts);
542 th->checksum = tcp_compute_checksum (tc, b);
544 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
547 tcp_zero_rwnd_sent_on (tc);
549 tcp_zero_rwnd_sent_off (tc);
553 * Convert buffer to ACK
556 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
558 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
559 TCP_EVT (TCP_EVT_ACK_SENT, tc);
560 tc->rcv_las = tc->rcv_nxt;
564 * Convert buffer to FIN-ACK
567 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
569 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
573 * Convert buffer to SYN
576 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
578 u8 tcp_hdr_opts_len, tcp_opts_len;
581 tcp_options_t snd_opts;
583 initial_wnd = tcp_initial_window_to_advertise (tc);
585 /* Make and write options */
586 clib_memset (&snd_opts, 0, sizeof (snd_opts));
587 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
588 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
590 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
591 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
593 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
594 tcp_options_write ((u8 *) (th + 1), &snd_opts);
595 th->checksum = tcp_compute_checksum (tc, b);
599 * Convert buffer to SYN-ACK
602 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
604 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
605 u8 tcp_opts_len, tcp_hdr_opts_len;
609 clib_memset (snd_opts, 0, sizeof (*snd_opts));
610 initial_wnd = tcp_initial_window_to_advertise (tc);
611 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
612 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
614 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
615 tc->rcv_nxt, tcp_hdr_opts_len,
616 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
617 tcp_options_write ((u8 *) (th + 1), snd_opts);
619 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
620 th->checksum = tcp_compute_checksum (tc, b);
624 tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
625 u8 is_ip4, u32 fib_index, u8 flush)
627 vlib_main_t *vm = wrk->vm;
628 u32 *to_next, next_index;
631 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
634 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
635 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
637 /* Send to IP lookup */
638 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
639 tcp_trajectory_add_start (b, 1);
641 f = wrk->ip_lookup_tx_frames[!is_ip4];
644 f = vlib_get_frame_to_node (vm, next_index);
646 wrk->ip_lookup_tx_frames[!is_ip4] = f;
649 to_next = vlib_frame_vector_args (f);
650 to_next[f->n_vectors] = bi;
652 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
654 vlib_put_frame_to_node (vm, next_index, f);
655 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
660 tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b,
661 u32 bi, u8 is_ip4, u32 fib_index)
663 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1);
667 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
668 u8 is_ip4, u32 fib_index)
670 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0);
671 if (wrk->vm->thread_index == 0 && vlib_num_workers ())
672 session_flush_frames_main_thread (wrk->vm);
676 tcp_enqueue_to_output_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
679 u32 *to_next, next_index;
682 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
685 /* Decide where to send the packet */
686 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
687 tcp_trajectory_add_start (b, 2);
689 /* Get frame to v4/6 output node */
690 f = wrk->tx_frames[!is_ip4];
693 f = vlib_get_frame_to_node (wrk->vm, next_index);
695 wrk->tx_frames[!is_ip4] = f;
697 to_next = vlib_frame_vector_args (f);
698 to_next[f->n_vectors] = bi;
700 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
702 vlib_put_frame_to_node (wrk->vm, next_index, f);
703 wrk->tx_frames[!is_ip4] = 0;
708 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
711 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 0);
715 tcp_enqueue_to_output_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
718 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 1);
720 #endif /* CLIB_MARCH_VARIANT */
723 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
724 tcp_state_t state, u8 thread_index, u8 is_ip4)
729 ip4_address_t src_ip40, dst_ip40;
730 ip6_address_t src_ip60, dst_ip60;
731 u16 src_port, dst_port;
736 /* Find IP and TCP headers */
737 th0 = tcp_buffer_hdr (b0);
739 /* Save src and dst ip */
742 ih4 = vlib_buffer_get_current (b0);
743 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
744 src_ip40.as_u32 = ih4->src_address.as_u32;
745 dst_ip40.as_u32 = ih4->dst_address.as_u32;
749 ih6 = vlib_buffer_get_current (b0);
750 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
751 clib_memcpy_fast (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
752 clib_memcpy_fast (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
755 src_port = th0->src_port;
756 dst_port = th0->dst_port;
758 /* Try to determine what/why we're actually resetting */
759 if (state == TCP_STATE_CLOSED)
764 tmp = clib_net_to_host_u32 (th0->seq_number);
766 /* Got a SYN for no listener. */
767 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
768 ack = clib_host_to_net_u32 (tmp + 1);
773 flags = TCP_FLAG_RST;
774 seq = th0->ack_number;
778 tcp_reuse_buffer (vm, b0);
779 tcp_trajectory_add_start (b0, 4);
780 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
781 sizeof (tcp_header_t), flags, 0);
785 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
787 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
792 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
794 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
801 #ifndef CLIB_MARCH_VARIANT
803 * Send reset without reusing existing buffer
805 * It extracts connection info out of original packet
808 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
809 u32 thread_index, u8 is_ip4)
811 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
812 vlib_main_t *vm = wrk->vm;
814 u32 bi, sw_if_index, fib_index;
815 u8 tcp_hdr_len, flags = 0;
816 tcp_header_t *th, *pkt_th;
818 ip4_header_t *ih4, *pkt_ih4;
819 ip6_header_t *ih6, *pkt_ih6;
820 fib_protocol_t fib_proto;
822 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
825 b = vlib_get_buffer (vm, bi);
826 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
827 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
828 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
829 tcp_init_buffer (vm, b);
831 /* Make and write options */
832 tcp_hdr_len = sizeof (tcp_header_t);
836 pkt_ih4 = vlib_buffer_get_current (pkt);
837 pkt_th = ip4_next_header (pkt_ih4);
841 pkt_ih6 = vlib_buffer_get_current (pkt);
842 pkt_th = ip6_next_header (pkt_ih6);
845 if (tcp_ack (pkt_th))
847 flags = TCP_FLAG_RST;
848 seq = pkt_th->ack_number;
849 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
853 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
855 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
858 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
859 seq, ack, tcp_hdr_len, flags, 0);
861 /* Swap src and dst ip */
864 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
865 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
866 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
867 (!(tc->flags & TCP_CONN_NO_CSUM_OFFLOAD)));
868 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
873 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
875 ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
876 &pkt_ih6->src_address, IP_PROTOCOL_TCP);
877 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
881 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index);
882 TCP_EVT (TCP_EVT_RST_SENT, tc);
883 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
884 TCP_ERROR_RST_SENT, 1);
888 * Build and set reset packet for connection
891 tcp_send_reset (tcp_connection_t * tc)
893 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
894 vlib_main_t *vm = wrk->vm;
898 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
901 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
903 b = vlib_get_buffer (vm, bi);
904 tcp_init_buffer (vm, b);
906 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
907 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
908 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
909 flags = TCP_FLAG_RST;
910 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
911 tc->rcv_nxt, tcp_hdr_opts_len, flags,
913 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
914 th->checksum = tcp_compute_checksum (tc, b);
915 ASSERT (opts_write_len == tc->snd_opts_len);
916 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
917 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
918 TCP_EVT (TCP_EVT_RST_SENT, tc);
919 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
920 TCP_ERROR_RST_SENT, 1);
924 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
927 tcp_header_t *th = vlib_buffer_get_current (b);
928 vlib_main_t *vm = wrk->vm;
932 ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
933 &tc->c_rmt_ip4, IP_PROTOCOL_TCP,
934 (!(tc->flags & TCP_CONN_NO_CSUM_OFFLOAD)));
935 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
942 ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
943 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
944 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
952 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
953 * The packet is not forwarded through tcpx_output to avoid doing lookups
954 * in the half_open pool.
957 tcp_send_syn (tcp_connection_t * tc)
959 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
960 vlib_main_t *vm = wrk->vm;
965 * Setup retransmit and establish timers before requesting buffer
966 * such that we can return if we've ran out.
968 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
969 tc->rto * TCP_TO_TIMER_TICK);
971 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
973 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
977 b = vlib_get_buffer (vm, bi);
978 tcp_init_buffer (vm, b);
979 tcp_make_syn (tc, b);
981 /* Measure RTT with this */
982 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
983 tc->rtt_seq = tc->snd_nxt;
986 tcp_push_ip_hdr (wrk, tc, b);
987 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
988 TCP_EVT (TCP_EVT_SYN_SENT, tc);
992 tcp_send_synack (tcp_connection_t * tc)
994 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
995 vlib_main_t *vm = wrk->vm;
999 tcp_retransmit_timer_force_update (tc);
1001 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1003 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1007 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1008 b = vlib_get_buffer (vm, bi);
1009 tcp_init_buffer (vm, b);
1010 tcp_make_synack (tc, b);
1011 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1012 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
1016 * Flush tx frame populated by retransmits and timer pops
1019 tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4)
1021 if (wrk->tx_frames[!is_ip4])
1024 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
1025 vlib_put_frame_to_node (wrk->vm, next_index, wrk->tx_frames[!is_ip4]);
1026 wrk->tx_frames[!is_ip4] = 0;
1031 * Flush ip lookup tx frames populated by timer pops
1034 tcp_flush_frame_to_ip_lookup (tcp_worker_ctx_t * wrk, u8 is_ip4)
1036 if (wrk->ip_lookup_tx_frames[!is_ip4])
1039 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
1040 vlib_put_frame_to_node (wrk->vm, next_index,
1041 wrk->ip_lookup_tx_frames[!is_ip4]);
1042 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
1047 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
1050 tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk)
1052 tcp_flush_frame_to_output (wrk, 1);
1053 tcp_flush_frame_to_output (wrk, 0);
1054 tcp_flush_frame_to_ip_lookup (wrk, 1);
1055 tcp_flush_frame_to_ip_lookup (wrk, 0);
1062 tcp_send_fin (tcp_connection_t * tc)
1064 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1065 vlib_main_t *vm = wrk->vm;
1070 fin_snt = tc->flags & TCP_CONN_FINSNT;
1074 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1076 /* Out of buffers so program fin retransmit ASAP */
1077 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1081 /* Make sure retransmit retries a fin not data */
1082 tc->flags |= TCP_CONN_FINSNT;
1086 tcp_retransmit_timer_force_update (tc);
1087 b = vlib_get_buffer (vm, bi);
1088 tcp_init_buffer (vm, b);
1089 tcp_make_fin (tc, b);
1090 tcp_enqueue_to_output_now (wrk, b, bi, tc->c_is_ip4);
1091 TCP_EVT (TCP_EVT_FIN_SENT, tc);
1092 /* Account for the FIN */
1096 tc->flags |= TCP_CONN_FINSNT;
1097 tc->flags &= ~TCP_CONN_FINPNDG;
1098 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
1103 * Push TCP header and update connection variables. Should only be called
1104 * for segments with data, not for 'control' packets.
1107 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
1108 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
1110 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
1111 u32 advertise_wnd, data_len;
1112 tcp_main_t *tm = &tcp_main;
1115 data_len = b->current_length;
1116 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1117 data_len += b->total_length_not_including_first_buffer;
1119 vnet_buffer (b)->tcp.flags = 0;
1120 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
1123 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1125 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
1128 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1130 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
1132 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
1134 if (seq_geq (tc->psh_seq, snd_nxt)
1135 && seq_lt (tc->psh_seq, snd_nxt + data_len))
1136 flags |= TCP_FLAG_PSH;
1138 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
1139 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1144 clib_memcpy_fast ((u8 *) (th + 1),
1145 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1150 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1151 ASSERT (len == tc->snd_opts_len);
1155 * Update connection variables
1159 tc->snd_nxt += data_len;
1160 tc->rcv_las = tc->rcv_nxt;
1162 tc->bytes_out += data_len;
1163 tc->data_segs_out += 1;
1166 th->checksum = tcp_compute_checksum (tc, b);
1168 TCP_EVT (TCP_EVT_PKTIZE, tc);
1172 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
1174 tcp_connection_t *tc = (tcp_connection_t *) tconn;
1176 if (tc->flags & TCP_CONN_TRACK_BURST)
1178 tcp_bt_check_app_limited (tc);
1179 tcp_bt_track_tx (tc);
1180 tc->flags &= ~TCP_CONN_TRACK_BURST;
1183 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1184 /* update_snd_nxt */ 1);
1186 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1187 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1188 /* If not tracking an ACK, start tracking */
1189 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1191 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1192 tc->rtt_seq = tc->snd_nxt;
1194 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1196 tcp_retransmit_timer_set (tc);
1199 tcp_trajectory_add_start (b, 3);
1204 tcp_send_ack (tcp_connection_t * tc)
1206 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1207 vlib_main_t *vm = wrk->vm;
1211 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1213 tcp_update_rcv_wnd (tc);
1216 b = vlib_get_buffer (vm, bi);
1217 tcp_init_buffer (vm, b);
1218 tcp_make_ack (tc, b);
1219 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1223 tcp_program_ack (tcp_connection_t * tc)
1225 if (!(tc->flags & TCP_CONN_SNDACK))
1227 session_add_self_custom_tx_evt (&tc->connection, 1);
1228 tc->flags |= TCP_CONN_SNDACK;
1233 tcp_program_dupack (tcp_connection_t * tc)
1235 if (!(tc->flags & TCP_CONN_SNDACK))
1237 session_add_self_custom_tx_evt (&tc->connection, 1);
1238 tc->flags |= TCP_CONN_SNDACK;
1240 if (tc->pending_dupacks < 255)
1241 tc->pending_dupacks += 1;
1245 tcp_program_retransmit (tcp_connection_t * tc)
1247 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1249 session_add_self_custom_tx_evt (&tc->connection, 0);
1250 tc->flags |= TCP_CONN_RXT_PENDING;
1255 * Delayed ack timer handler
1257 * Sends delayed ACK when timer expires
1260 tcp_timer_delack_handler (u32 index)
1262 u32 thread_index = vlib_get_thread_index ();
1263 tcp_connection_t *tc;
1265 tc = tcp_connection_get (index, thread_index);
1266 tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID;
1271 * Send window update ack
1273 * Ensures that it will be sent only once, after a zero rwnd has been
1274 * advertised in a previous ack, and only if rwnd has grown beyond a
1275 * configurable value.
1278 tcp_send_window_update_ack (tcp_connection_t * tc)
1280 if (tcp_zero_rwnd_sent (tc))
1282 tcp_update_rcv_wnd (tc);
1283 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1285 tcp_zero_rwnd_sent_off (tc);
1286 tcp_program_ack (tc);
1292 * Allocate a new buffer and build a new tcp segment
1294 * @param wrk tcp worker
1295 * @param tc connection for which the segment will be allocated
1296 * @param offset offset of the first byte in the tx fifo
1297 * @param max_deq_byte segment size
1298 * @param[out] b pointer to buffer allocated
1300 * @return the number of bytes in the segment or 0 if buffer cannot be
1301 * allocated or no data available
1304 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1305 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1307 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1308 vlib_main_t *vm = wrk->vm;
1313 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1318 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1321 * Allocate and fill in buffer(s)
1324 /* Easy case, buffer size greater than mss */
1325 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1327 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1329 *b = vlib_get_buffer (vm, bi);
1330 data = tcp_init_buffer (vm, *b);
1331 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1333 ASSERT (n_bytes == max_deq_bytes);
1334 b[0]->current_length = n_bytes;
1335 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1336 /* burst */ 0, /* update_snd_nxt */ 0);
1338 /* Split mss into multiple buffers */
1341 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1342 u16 n_peeked, len_to_deq;
1343 vlib_buffer_t *chain_b, *prev_b;
1346 /* Make sure we have enough buffers */
1347 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1348 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1349 CLIB_CACHE_LINE_BYTES);
1350 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1351 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1354 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1358 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1359 data = tcp_init_buffer (vm, *b);
1360 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1362 TRANSPORT_MAX_HDRS_LEN);
1363 b[0]->current_length = n_bytes;
1364 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1365 b[0]->total_length_not_including_first_buffer = 0;
1366 max_deq_bytes -= n_bytes;
1369 for (i = 1; i < n_bufs_per_seg; i++)
1372 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1373 chain_bi = wrk->tx_buffers[--n_bufs];
1374 chain_b = vlib_get_buffer (vm, chain_bi);
1375 chain_b->current_data = 0;
1376 data = vlib_buffer_get_current (chain_b);
1377 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1380 ASSERT (n_peeked == len_to_deq);
1381 n_bytes += n_peeked;
1382 chain_b->current_length = n_peeked;
1383 chain_b->next_buffer = 0;
1385 /* update previous buffer */
1386 prev_b->next_buffer = chain_bi;
1387 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1389 max_deq_bytes -= n_peeked;
1390 b[0]->total_length_not_including_first_buffer += n_peeked;
1393 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1394 /* burst */ 0, /* update_snd_nxt */ 0);
1396 if (PREDICT_FALSE (n_bufs))
1398 clib_warning ("not all buffers consumed");
1399 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1403 ASSERT (n_bytes > 0);
1404 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1410 * Build a retransmit segment
1412 * @return the number of bytes in the segment or 0 if there's nothing to
1416 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1417 tcp_connection_t * tc, u32 offset,
1418 u32 max_deq_bytes, vlib_buffer_t ** b)
1420 u32 start, available_bytes;
1423 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1424 ASSERT (max_deq_bytes != 0);
1427 * Make sure we can retransmit something
1429 available_bytes = transport_max_tx_dequeue (&tc->connection);
1430 ASSERT (available_bytes >= offset);
1431 available_bytes -= offset;
1432 if (!available_bytes)
1435 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1436 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1438 /* Start is beyond snd_congestion */
1439 start = tc->snd_una + offset;
1440 if (seq_geq (start, tc->snd_congestion))
1443 /* Don't overshoot snd_congestion */
1444 if (seq_gt (start + max_deq_bytes, tc->snd_congestion))
1446 max_deq_bytes = tc->snd_congestion - start;
1447 if (max_deq_bytes == 0)
1451 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1455 tc->snd_rxt_bytes += n_bytes;
1457 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1458 tcp_bt_track_rxt (tc, start, start + n_bytes);
1460 tc->bytes_retrans += n_bytes;
1461 tc->segs_retrans += 1;
1462 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1468 tcp_check_sack_reneging (tcp_connection_t * tc)
1470 sack_scoreboard_t *sb = &tc->sack_sb;
1471 sack_scoreboard_hole_t *hole;
1473 hole = scoreboard_first_hole (sb);
1474 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1477 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1481 * Reset congestion control, switch cwnd to loss window and try again.
1484 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1486 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1488 tc->prev_ssthresh = tc->ssthresh;
1489 tc->prev_cwnd = tc->cwnd;
1491 /* If we entrered loss without fast recovery, notify cc algo of the
1492 * congestion event such that it can update ssthresh and its state */
1493 if (!tcp_in_fastrecovery (tc))
1494 tcp_cc_congestion (tc);
1496 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1500 tc->cwnd_acc_bytes = 0;
1501 tc->tr_occurences += 1;
1502 tcp_recovery_on (tc);
1506 tcp_timer_retransmit_handler (u32 tc_index)
1508 u32 thread_index = vlib_get_thread_index ();
1509 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1510 vlib_main_t *vm = wrk->vm;
1511 tcp_connection_t *tc;
1512 vlib_buffer_t *b = 0;
1515 tc = tcp_connection_get (tc_index, thread_index);
1517 /* Note: the connection may have been closed and pool_put */
1518 if (PREDICT_FALSE (tc == 0 || tc->state == TCP_STATE_SYN_SENT))
1521 tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
1523 /* Wait-close and retransmit could pop at the same time */
1524 if (tc->state == TCP_STATE_CLOSED)
1527 if (tc->state >= TCP_STATE_ESTABLISHED)
1529 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1531 /* Lost FIN, retransmit and return */
1532 if (tc->flags & TCP_CONN_FINSNT)
1536 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1540 /* Shouldn't be here. This condition is tricky because it has to take
1541 * into account boff > 0 due to persist timeout. */
1542 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1543 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1544 && !tcp_flight_size (tc)))
1546 ASSERT (!tcp_in_recovery (tc));
1551 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1552 * to persist timer timeout */
1553 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1556 tcp_update_rto (tc);
1559 /* Peer is dead or network connectivity is lost. Close connection.
1560 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1561 * a min rto of 0.2s we need to retry about 8 times. */
1562 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1564 tcp_send_reset (tc);
1565 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1566 session_transport_closing_notify (&tc->connection);
1567 tcp_connection_timers_reset (tc);
1568 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1572 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1573 tcp_check_sack_reneging (tc);
1575 /* Update send congestion to make sure that rxt has data to send */
1576 tc->snd_congestion = tc->snd_nxt;
1578 /* Send the first unacked segment. If we're short on buffers, return
1579 * as soon as possible */
1580 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1583 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1587 bi = vlib_get_buffer_index (vm, b);
1588 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1590 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1591 tcp_retransmit_timer_force_update (tc);
1594 if (tc->rto_boff == 1)
1596 tcp_cc_init_rxt_timeout (tc);
1597 /* Record timestamp. Eifel detection algorithm RFC3522 */
1598 tc->snd_rxt_ts = tcp_tstamp (tc);
1601 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1602 scoreboard_init_high_rxt (&tc->sack_sb, tc->snd_una + tc->snd_mss);
1604 tcp_program_retransmit (tc);
1606 /* Retransmit SYN-ACK */
1607 else if (tc->state == TCP_STATE_SYN_RCVD)
1609 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1613 /* Passive open establish timeout */
1614 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1616 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1617 tcp_connection_timers_reset (tc);
1618 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
1622 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1624 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1629 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1630 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1632 tcp_retransmit_timer_force_update (tc);
1634 b = vlib_get_buffer (vm, bi);
1635 tcp_init_buffer (vm, b);
1636 tcp_make_synack (tc, b);
1637 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1639 /* Retransmit timer already updated, just enqueue to output */
1640 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1644 ASSERT (tc->state == TCP_STATE_CLOSED);
1650 * SYN retransmit timer handler. Active open only.
1653 tcp_timer_retransmit_syn_handler (u32 tc_index)
1655 u32 thread_index = vlib_get_thread_index ();
1656 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1657 vlib_main_t *vm = wrk->vm;
1658 tcp_connection_t *tc;
1659 vlib_buffer_t *b = 0;
1662 tc = tcp_half_open_connection_get (tc_index);
1664 /* Note: the connection may have transitioned to ESTABLISHED... */
1665 if (PREDICT_FALSE (tc == 0 || tc->state != TCP_STATE_SYN_SENT))
1668 tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1670 /* Half-open connection actually moved to established but we were
1671 * waiting for syn retransmit to pop to call cleanup from the right
1673 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1675 if (tcp_half_open_connection_cleanup (tc))
1676 TCP_DBG ("could not remove half-open connection");
1680 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1683 /* Active open establish timeout */
1684 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1686 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
1687 tcp_connection_cleanup (tc);
1691 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1693 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1697 /* Try without increasing RTO a number of times. If this fails,
1698 * start growing RTO exponentially */
1700 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1701 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1703 b = vlib_get_buffer (vm, bi);
1704 tcp_init_buffer (vm, b);
1705 tcp_make_syn (tc, b);
1707 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1709 /* This goes straight to ipx_lookup */
1710 tcp_push_ip_hdr (wrk, tc, b);
1711 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1713 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1714 tc->rto * TCP_TO_TIMER_TICK);
1718 * Got 0 snd_wnd from peer, try to do something about it.
1722 tcp_timer_persist_handler (u32 index)
1724 u32 thread_index = vlib_get_thread_index ();
1725 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1726 u32 bi, max_snd_bytes, available_bytes, offset;
1727 tcp_main_t *tm = vnet_get_tcp_main ();
1728 vlib_main_t *vm = wrk->vm;
1729 tcp_connection_t *tc;
1734 tc = tcp_connection_get_if_valid (index, thread_index);
1738 /* Make sure timer handle is set to invalid */
1739 tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID;
1741 /* Problem already solved or worse */
1742 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1743 || (tc->flags & TCP_CONN_FINSNT))
1746 available_bytes = transport_max_tx_dequeue (&tc->connection);
1747 offset = tc->snd_nxt - tc->snd_una;
1749 /* Reprogram persist if no new bytes available to send. We may have data
1751 if (!available_bytes)
1753 tcp_persist_timer_set (tc);
1757 if (available_bytes <= offset)
1759 ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
1763 /* Increment RTO backoff */
1765 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1768 * Try to force the first unsent segment (or buffer)
1770 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1772 tcp_persist_timer_set (tc);
1775 b = vlib_get_buffer (vm, bi);
1776 data = tcp_init_buffer (vm, b);
1778 tcp_validate_txf_size (tc, offset);
1779 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1780 max_snd_bytes = clib_min (tc->snd_mss,
1781 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1782 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1784 b->current_length = n_bytes;
1785 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1786 || tc->snd_nxt == tc->snd_una_max
1787 || tc->rto_boff > 1));
1789 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1790 /* burst */ 0, /* update_snd_nxt */ 1);
1791 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1792 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1793 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1795 /* Just sent new data, enable retransmit */
1796 tcp_retransmit_timer_update (tc);
1800 * Retransmit first unacked segment
1803 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1805 vlib_main_t *vm = wrk->vm;
1809 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1811 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1815 bi = vlib_get_buffer_index (vm, b);
1816 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1822 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1825 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1826 vlib_main_t *vm = wrk->vm;
1827 vlib_buffer_t *b = 0;
1829 offset = tc->snd_nxt - tc->snd_una;
1830 available_wnd = tc->snd_wnd - offset;
1831 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1833 while (n_segs < burst_size)
1835 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1839 bi = vlib_get_buffer_index (vm, b);
1840 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1841 offset += n_written;
1844 tc->snd_nxt += n_written;
1845 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1853 * Estimate send space using proportional rate reduction (RFC6937)
1856 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1861 pipe = tcp_flight_size (tc);
1862 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1864 if (pipe > tc->ssthresh)
1866 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1871 int limit = tc->prr_delivered - prr_out + tc->snd_mss;
1872 space = clib_min (tc->ssthresh - pipe, limit);
1874 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1878 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1879 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1880 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1883 * Do retransmit with SACKs
1886 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1889 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1890 sack_scoreboard_hole_t *hole;
1891 vlib_main_t *vm = wrk->vm;
1892 vlib_buffer_t *b = 0;
1893 sack_scoreboard_t *sb;
1896 u8 snd_limited = 0, can_rescue = 0;
1898 ASSERT (tcp_in_cong_recovery (tc));
1900 if (tcp_in_recovery (tc))
1901 snd_space = tcp_available_cc_snd_space (tc);
1903 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1905 if (snd_space < tc->snd_mss)
1907 /* We're cc constrained so don't accumulate tokens */
1908 transport_connection_tx_pacer_reset_bucket (&tc->connection,
1910 clib_time.last_cpu_time);
1914 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1916 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1918 max_deq = transport_max_tx_dequeue (&tc->connection);
1919 max_deq -= tc->snd_nxt - tc->snd_una;
1921 while (snd_space > 0 && n_segs < burst_size)
1923 hole = scoreboard_next_rxt_hole (sb, hole, max_deq, &can_rescue,
1927 /* We are out of lost holes to retransmit so send some new data. */
1930 u32 n_segs_new, av_window;
1931 av_window = tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1932 snd_space = clib_min (snd_space, av_window);
1933 snd_space = clib_min (max_deq, snd_space);
1934 burst_size = clib_min (burst_size - n_segs,
1935 snd_space / tc->snd_mss);
1936 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1937 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1938 if (max_deq > n_segs_new * tc->snd_mss)
1939 tcp_program_retransmit (tc);
1941 n_segs += n_segs_new;
1945 if (tcp_in_recovery (tc) || !can_rescue
1946 || scoreboard_rescue_rxt_valid (sb, tc))
1949 /* If rescue rxt undefined or less than snd_una then one segment of
1950 * up to SMSS octets that MUST include the highest outstanding
1951 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1952 * RecoveryPoint. HighRxt MUST NOT be updated.
1954 max_bytes = clib_min (tc->snd_mss,
1955 tc->snd_congestion - tc->snd_una);
1956 max_bytes = clib_min (max_bytes, snd_space);
1957 offset = tc->snd_congestion - tc->snd_una - max_bytes;
1958 sb->rescue_rxt = tc->snd_congestion;
1959 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1964 bi = vlib_get_buffer_index (vm, b);
1965 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1970 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1971 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1975 offset = sb->high_rxt - tc->snd_una;
1976 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1978 ASSERT (n_written <= snd_space);
1980 /* Nothing left to retransmit */
1984 bi = vlib_get_buffer_index (vm, b);
1985 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1987 sb->high_rxt += n_written;
1988 snd_space -= n_written;
1993 tcp_program_retransmit (tc);
2001 * Fast retransmit without SACK info
2004 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
2007 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now;
2008 vlib_main_t *vm = wrk->vm;
2009 int snd_space, n_segs = 0;
2012 ASSERT (tcp_in_fastrecovery (tc));
2013 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
2015 snd_space = tcp_available_cc_snd_space (tc);
2017 if (!tcp_fastrecovery_first (tc))
2020 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
2022 while (snd_space > 0 && n_segs < burst_size)
2024 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
2027 /* Nothing left to retransmit */
2031 bi = vlib_get_buffer_index (vm, b);
2032 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
2033 snd_space -= n_written;
2034 offset += n_written;
2038 if (n_segs == burst_size)
2043 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
2044 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
2047 max_deq = transport_max_tx_dequeue (&tc->connection);
2048 max_deq -= tc->snd_nxt - tc->snd_una;
2051 snd_space = clib_min (max_deq, snd_space);
2052 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
2053 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
2054 if (max_deq > n_segs_now * tc->snd_mss)
2055 tcp_program_retransmit (tc);
2056 n_segs += n_segs_now;
2060 tcp_fastrecovery_first_off (tc);
2065 * Do fast retransmit
2068 tcp_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, u32 burst_size)
2070 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2071 return tcp_retransmit_sack (wrk, tc, burst_size);
2073 return tcp_retransmit_no_sack (wrk, tc, burst_size);
2077 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
2081 if (!tc->pending_dupacks)
2087 /* If we're supposed to send dupacks but have no ooo data
2088 * send only one ack */
2089 if (!vec_len (tc->snd_sacks))
2095 /* Start with first sack block */
2096 tc->snd_sack_pos = 0;
2098 /* Generate enough dupacks to cover all sack blocks. Do not generate
2099 * more sacks than the number of packets received. But do generate at
2100 * least 3, i.e., the number needed to signal congestion, if needed. */
2101 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
2102 n_acks = clib_min (n_acks, tc->pending_dupacks);
2103 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
2104 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
2107 if (n_acks < max_burst_size)
2109 tc->pending_dupacks = 0;
2110 tc->snd_sack_pos = 0;
2111 tc->dupacks_out += n_acks;
2116 TCP_DBG ("constrained by burst size");
2117 tc->pending_dupacks = n_acks - max_burst_size;
2118 tc->dupacks_out += max_burst_size;
2119 tcp_program_dupack (tc);
2120 return max_burst_size;
2125 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
2127 u32 n_segs = 0, burst_size, sent_bytes, burst_bytes;
2128 tcp_worker_ctx_t *wrk;
2130 wrk = tcp_get_worker (tc->c_thread_index);
2131 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection,
2133 clib_time.last_cpu_time);
2134 burst_size = clib_min (max_burst_size, burst_bytes / tc->snd_mss);
2137 tcp_program_retransmit (tc);
2141 n_segs = tcp_retransmit (wrk, tc, burst_size);
2142 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2143 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
2148 tcp_session_custom_tx (void *conn, u32 max_burst_size)
2150 tcp_connection_t *tc = (tcp_connection_t *) conn;
2153 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2155 tc->flags &= ~TCP_CONN_RXT_PENDING;
2156 n_segs = tcp_do_retransmit (tc, max_burst_size);
2157 max_burst_size -= n_segs;
2160 if (!(tc->flags & TCP_CONN_SNDACK))
2163 tc->flags &= ~TCP_CONN_SNDACK;
2165 /* We have retransmitted packets and no dupack */
2166 if (n_segs && !tc->pending_dupacks)
2169 if (!max_burst_size)
2171 tcp_program_ack (tc);
2172 return max_burst_size;
2175 n_segs += tcp_send_acks (tc, max_burst_size);
2179 #endif /* CLIB_MARCH_VARIANT */
2182 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2183 u16 * next0, u32 * error0)
2185 ip_adjacency_t *adj;
2188 /* Not thread safe but as long as the connection exists the adj should
2190 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2192 if (ai == ADJ_INDEX_INVALID)
2194 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2195 *next0 = TCP_OUTPUT_NEXT_DROP;
2196 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2201 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2202 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2203 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2204 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2207 *next0 = TCP_OUTPUT_NEXT_DROP;
2208 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2210 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2214 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2215 u32 * to_next, u32 n_bufs)
2217 u32 n_trace = vlib_get_trace_count (vm, node);
2218 tcp_connection_t *tc;
2224 for (i = 0; i < clib_min (n_trace, n_bufs); i++)
2226 b = vlib_get_buffer (vm, to_next[i]);
2227 th = vlib_buffer_get_current (b);
2228 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2230 t = vlib_add_trace (vm, node, b, sizeof (*t));
2231 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2232 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2237 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2238 tcp_connection_t * tc0, u8 is_ip4)
2240 u8 __clib_unused *ih0;
2241 tcp_header_t __clib_unused *th0 = vlib_buffer_get_current (b0);
2243 TCP_EVT (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length);
2246 ih0 = vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2248 (!(tc0->flags & TCP_CONN_NO_CSUM_OFFLOAD)));
2250 ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2256 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2258 if (PREDICT_TRUE (!(b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)))
2261 b->current_length + b->total_length_not_including_first_buffer -
2262 sizeof (tcp_header_t) - tc->snd_opts_len;
2264 if (data_len > tc->snd_mss)
2266 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2267 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2268 b->flags |= VNET_BUFFER_F_GSO;
2269 vnet_buffer2 (b)->gso_l4_hdr_sz =
2270 sizeof (tcp_header_t) + tc->snd_opts_len;
2271 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2276 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2277 vlib_node_runtime_t * error_node, u16 * next0,
2280 /* If next_index is not drop use it */
2281 if (tc0->next_node_index)
2283 *next0 = tc0->next_node_index;
2284 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2288 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2291 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2292 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2298 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2299 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2301 if (PREDICT_FALSE (error0))
2303 b0->error = error_node->errors[error0];
2308 if (!TCP_ALWAYS_ACK)
2309 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
2315 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2316 vlib_frame_t * frame, int is_ip4)
2318 u32 n_left_from, *from, thread_index = vm->thread_index;
2319 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2320 u16 nexts[VLIB_FRAME_SIZE], *next;
2321 vlib_node_runtime_t *error_node;
2323 error_node = vlib_node_get_runtime (vm, tcp_node_index (output, is_ip4));
2325 from = vlib_frame_vector_args (frame);
2326 n_left_from = frame->n_vectors;
2327 tcp_set_time_now (tcp_get_worker (thread_index));
2329 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2330 tcp46_output_trace_frame (vm, node, from, n_left_from);
2332 vlib_get_buffers (vm, from, bufs, n_left_from);
2336 while (n_left_from >= 4)
2338 tcp_connection_t *tc0, *tc1;
2341 vlib_prefetch_buffer_header (b[2], STORE);
2342 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2344 vlib_prefetch_buffer_header (b[3], STORE);
2345 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2348 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2350 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2353 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2355 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2356 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2358 tcp_check_if_gso (tc0, b[0]);
2359 tcp_check_if_gso (tc1, b[1]);
2361 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2362 tcp_output_handle_packet (tc1, b[1], error_node, &next[1], is_ip4);
2368 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2369 tcp_check_if_gso (tc0, b[0]);
2370 tcp_output_handle_packet (tc0, b[0], error_node, &next[0],
2375 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2376 next[0] = TCP_OUTPUT_NEXT_DROP;
2380 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2381 tcp_check_if_gso (tc1, b[1]);
2382 tcp_output_handle_packet (tc1, b[1], error_node, &next[1],
2387 b[1]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2388 next[1] = TCP_OUTPUT_NEXT_DROP;
2396 while (n_left_from > 0)
2398 tcp_connection_t *tc0;
2400 if (n_left_from > 1)
2402 vlib_prefetch_buffer_header (b[1], STORE);
2403 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2406 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2409 if (PREDICT_TRUE (tc0 != 0))
2411 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2412 tcp_check_if_gso (tc0, b[0]);
2413 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2417 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2418 next[0] = TCP_OUTPUT_NEXT_DROP;
2426 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2427 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2428 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2429 return frame->n_vectors;
2432 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2433 vlib_frame_t * from_frame)
2435 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2438 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2439 vlib_frame_t * from_frame)
2441 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2445 VLIB_REGISTER_NODE (tcp4_output_node) =
2447 .name = "tcp4-output",
2448 /* Takes a vector of packets. */
2449 .vector_size = sizeof (u32),
2450 .n_errors = TCP_N_ERROR,
2451 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2452 .error_strings = tcp_error_strings,
2453 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2455 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2456 foreach_tcp4_output_next
2459 .format_buffer = format_tcp_header,
2460 .format_trace = format_tcp_tx_trace,
2465 VLIB_REGISTER_NODE (tcp6_output_node) =
2467 .name = "tcp6-output",
2468 /* Takes a vector of packets. */
2469 .vector_size = sizeof (u32),
2470 .n_errors = TCP_N_ERROR,
2471 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2472 .error_strings = tcp_error_strings,
2473 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2475 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2476 foreach_tcp6_output_next
2479 .format_buffer = format_tcp_header,
2480 .format_trace = format_tcp_tx_trace,
2484 typedef enum _tcp_reset_next
2486 TCP_RESET_NEXT_DROP,
2487 TCP_RESET_NEXT_IP_LOOKUP,
2491 #define foreach_tcp4_reset_next \
2492 _(DROP, "error-drop") \
2493 _(IP_LOOKUP, "ip4-lookup")
2495 #define foreach_tcp6_reset_next \
2496 _(DROP, "error-drop") \
2497 _(IP_LOOKUP, "ip6-lookup")
2500 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2501 vlib_frame_t * from_frame, u8 is_ip4)
2503 u32 n_left_from, next_index, *from, *to_next;
2504 u32 my_thread_index = vm->thread_index;
2506 from = vlib_frame_vector_args (from_frame);
2507 n_left_from = from_frame->n_vectors;
2509 next_index = node->cached_next_index;
2511 while (n_left_from > 0)
2515 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2517 while (n_left_from > 0 && n_left_to_next > 0)
2523 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2530 n_left_to_next -= 1;
2532 b0 = vlib_get_buffer (vm, bi0);
2534 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2535 my_thread_index, is_ip4))
2537 error0 = TCP_ERROR_LOOKUP_DROPS;
2538 next0 = TCP_RESET_NEXT_DROP;
2542 /* Prepare to send to IP lookup */
2543 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2544 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2547 b0->error = node->errors[error0];
2548 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2549 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2551 th0 = vlib_buffer_get_current (b0);
2553 th0 = ip4_next_header ((ip4_header_t *) th0);
2555 th0 = ip6_next_header ((ip6_header_t *) th0);
2556 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2557 clib_memcpy_fast (&t0->tcp_header, th0,
2558 sizeof (t0->tcp_header));
2561 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2562 n_left_to_next, bi0, next0);
2564 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2566 return from_frame->n_vectors;
2569 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2570 vlib_frame_t * from_frame)
2572 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2575 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2576 vlib_frame_t * from_frame)
2578 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2582 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2583 .name = "tcp4-reset",
2584 .vector_size = sizeof (u32),
2585 .n_errors = TCP_N_ERROR,
2586 .error_strings = tcp_error_strings,
2587 .n_next_nodes = TCP_RESET_N_NEXT,
2589 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2590 foreach_tcp4_reset_next
2593 .format_trace = format_tcp_tx_trace,
2598 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2599 .name = "tcp6-reset",
2600 .vector_size = sizeof (u32),
2601 .n_errors = TCP_N_ERROR,
2602 .error_strings = tcp_error_strings,
2603 .n_next_nodes = TCP_RESET_N_NEXT,
2605 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2606 foreach_tcp6_reset_next
2609 .format_trace = format_tcp_tx_trace,
2614 * fd.io coding-style-patch-verification: ON
2617 * eval: (c-set-style "gnu")