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 * Update max segment size we're able to process.
81 * The value is constrained by our interface's MTU and IP options. It is
82 * also what we advertise to our peer.
85 tcp_update_rcv_mss (tcp_connection_t * tc)
87 /* TODO find our iface MTU */
88 tc->mss = tcp_main.default_mtu - sizeof (tcp_header_t);
92 * TCP's initial window
95 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
97 /* RFC 6928 recommends the value lower. However at the time our connections
98 * are initialized, fifos may not be allocated. Therefore, advertise the
99 * smallest possible unscaled window size and update once fifos are
100 * assigned to the session.
103 tcp_update_rcv_mss (tc);
104 TCP_IW_N_SEGMENTS * tc->mss;
106 return TCP_MIN_RX_FIFO_SIZE;
110 * Compute initial window and scale factor. As per RFC1323, window field in
111 * SYN and SYN-ACK segments is never scaled.
114 tcp_initial_window_to_advertise (tcp_connection_t * tc)
116 tcp_main_t *tm = &tcp_main;
119 /* Initial wnd for SYN. Fifos are not allocated yet.
120 * Use some predefined value. For SYN-ACK we still want the
121 * scale to be computed in the same way */
122 max_fifo = tm->max_rx_fifo ? tm->max_rx_fifo : TCP_MAX_RX_FIFO_SIZE;
124 /* Compute rcv wscale only if peer advertised support for it */
125 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
126 tc->rcv_wscale = tcp_window_compute_scale (max_fifo);
128 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
130 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
134 tcp_update_rcv_wnd (tcp_connection_t * tc)
136 u32 available_space, wnd;
139 ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection));
142 * Figure out how much space we have available
144 available_space = transport_max_rx_enqueue (&tc->connection);
145 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
149 * Use the above and what we know about what we've previously advertised
150 * to compute the new window
152 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
154 /* Bad. Thou shalt not shrink */
155 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
157 wnd = clib_max (observed_wnd, 0);
158 TCP_EVT_DBG (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
162 wnd = available_space;
165 /* Make sure we have a multiple of rcv_wscale */
166 if (wnd && tc->rcv_wscale)
168 wnd &= ~((1 << tc->rcv_wscale) - 1);
170 wnd = 1 << tc->rcv_wscale;
173 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
177 * Compute and return window to advertise, scaled as per RFC1323
180 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
182 if (state < TCP_STATE_ESTABLISHED)
183 return tcp_initial_window_to_advertise (tc);
185 tcp_update_rcv_wnd (tc);
186 return tc->rcv_wnd >> tc->rcv_wscale;
190 * Write TCP options to segment.
193 tcp_options_write (u8 * data, tcp_options_t * opts)
196 u32 buf, seq_len = 4;
198 if (tcp_opts_mss (opts))
200 *data++ = TCP_OPTION_MSS;
201 *data++ = TCP_OPTION_LEN_MSS;
202 buf = clib_host_to_net_u16 (opts->mss);
203 clib_memcpy_fast (data, &buf, sizeof (opts->mss));
204 data += sizeof (opts->mss);
205 opts_len += TCP_OPTION_LEN_MSS;
208 if (tcp_opts_wscale (opts))
210 *data++ = TCP_OPTION_WINDOW_SCALE;
211 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
212 *data++ = opts->wscale;
213 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
216 if (tcp_opts_sack_permitted (opts))
218 *data++ = TCP_OPTION_SACK_PERMITTED;
219 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
220 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
223 if (tcp_opts_tstamp (opts))
225 *data++ = TCP_OPTION_TIMESTAMP;
226 *data++ = TCP_OPTION_LEN_TIMESTAMP;
227 buf = clib_host_to_net_u32 (opts->tsval);
228 clib_memcpy_fast (data, &buf, sizeof (opts->tsval));
229 data += sizeof (opts->tsval);
230 buf = clib_host_to_net_u32 (opts->tsecr);
231 clib_memcpy_fast (data, &buf, sizeof (opts->tsecr));
232 data += sizeof (opts->tsecr);
233 opts_len += TCP_OPTION_LEN_TIMESTAMP;
236 if (tcp_opts_sack (opts))
240 if (opts->n_sack_blocks != 0)
242 *data++ = TCP_OPTION_SACK_BLOCK;
243 *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
244 for (i = 0; i < opts->n_sack_blocks; i++)
246 buf = clib_host_to_net_u32 (opts->sacks[i].start);
247 clib_memcpy_fast (data, &buf, seq_len);
249 buf = clib_host_to_net_u32 (opts->sacks[i].end);
250 clib_memcpy_fast (data, &buf, seq_len);
253 opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
257 /* Terminate TCP options */
260 *data++ = TCP_OPTION_EOL;
261 opts_len += TCP_OPTION_LEN_EOL;
264 /* Pad with zeroes to a u32 boundary */
267 *data++ = TCP_OPTION_NOOP;
268 opts_len += TCP_OPTION_LEN_NOOP;
274 tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale)
278 opts->flags |= TCP_OPTS_FLAG_MSS;
279 opts->mss = tcp_main.default_mtu; /*XXX discover that */
280 len += TCP_OPTION_LEN_MSS;
282 opts->flags |= TCP_OPTS_FLAG_WSCALE;
283 opts->wscale = wnd_scale;
284 len += TCP_OPTION_LEN_WINDOW_SCALE;
286 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
287 opts->tsval = tcp_time_now ();
289 len += TCP_OPTION_LEN_TIMESTAMP;
293 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
294 len += TCP_OPTION_LEN_SACK_PERMITTED;
297 /* Align to needed boundary */
298 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
303 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
307 opts->flags |= TCP_OPTS_FLAG_MSS;
309 len += TCP_OPTION_LEN_MSS;
311 if (tcp_opts_wscale (&tc->rcv_opts))
313 opts->flags |= TCP_OPTS_FLAG_WSCALE;
314 opts->wscale = tc->rcv_wscale;
315 len += TCP_OPTION_LEN_WINDOW_SCALE;
318 if (tcp_opts_tstamp (&tc->rcv_opts))
320 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
321 opts->tsval = tcp_time_now ();
322 opts->tsecr = tc->tsval_recent;
323 len += TCP_OPTION_LEN_TIMESTAMP;
326 if (tcp_opts_sack_permitted (&tc->rcv_opts))
328 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
329 len += TCP_OPTION_LEN_SACK_PERMITTED;
332 /* Align to needed boundary */
333 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
338 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
344 if (tcp_opts_tstamp (&tc->rcv_opts))
346 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
347 opts->tsval = tcp_tstamp (tc);
348 opts->tsecr = tc->tsval_recent;
349 len += TCP_OPTION_LEN_TIMESTAMP;
351 if (tcp_opts_sack_permitted (&tc->rcv_opts))
353 if (vec_len (tc->snd_sacks))
355 opts->flags |= TCP_OPTS_FLAG_SACK;
356 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
357 tc->snd_sack_pos = 0;
358 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
359 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
360 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
361 TCP_OPTS_MAX_SACK_BLOCKS);
362 tc->snd_sack_pos += opts->n_sack_blocks;
363 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
367 /* Align to needed boundary */
368 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
373 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
378 case TCP_STATE_ESTABLISHED:
379 case TCP_STATE_CLOSE_WAIT:
380 case TCP_STATE_FIN_WAIT_1:
381 case TCP_STATE_LAST_ACK:
382 case TCP_STATE_CLOSING:
383 case TCP_STATE_FIN_WAIT_2:
384 case TCP_STATE_TIME_WAIT:
385 case TCP_STATE_CLOSED:
386 return tcp_make_established_options (tc, opts);
387 case TCP_STATE_SYN_RCVD:
388 return tcp_make_synack_options (tc, opts);
389 case TCP_STATE_SYN_SENT:
390 return tcp_make_syn_options (opts, tc->rcv_wscale);
392 clib_warning ("State not handled! %d", state);
398 * Update burst send vars
400 * - Updates snd_mss to reflect the effective segment size that we can send
401 * by taking into account all TCP options, including SACKs.
402 * - Cache 'on the wire' options for reuse
403 * - Updates receive window which can be reused for a burst.
405 * This should *only* be called when doing bursts
408 tcp_update_burst_snd_vars (tcp_connection_t * tc)
410 tcp_main_t *tm = &tcp_main;
412 /* Compute options to be used for connection. These may be reused when
413 * sending data or to compute the effective mss (snd_mss) */
414 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
415 TCP_STATE_ESTABLISHED);
417 /* XXX check if MTU has been updated */
418 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
419 ASSERT (tc->snd_mss > 0);
421 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
424 tcp_update_rcv_wnd (tc);
426 if (tc->flags & TCP_CONN_RATE_SAMPLE)
427 tc->flags |= TCP_CONN_TRACK_BURST;
429 if (tc->snd_una == tc->snd_nxt)
430 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
434 tcp_init_mss (tcp_connection_t * tc)
436 u16 default_min_mss = 536;
437 tcp_update_rcv_mss (tc);
439 /* TODO cache mss and consider PMTU discovery */
440 tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss);
442 if (tc->snd_mss < 45)
444 /* Assume that at least the min default mss works */
445 tc->snd_mss = default_min_mss;
446 tc->rcv_opts.mss = default_min_mss;
449 /* We should have enough space for 40 bytes of options */
450 ASSERT (tc->snd_mss > 45);
452 /* If we use timestamp option, account for it */
453 if (tcp_opts_tstamp (&tc->rcv_opts))
454 tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP;
456 #endif /* CLIB_MARCH_VARIANT */
459 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
461 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
462 vlib_buffer_free_one (vm, b->next_buffer);
463 /* Zero all flags but free list index and trace flag */
464 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
466 b->current_length = 0;
467 b->total_length_not_including_first_buffer = 0;
468 vnet_buffer (b)->tcp.flags = 0;
470 /* Leave enough space for headers */
471 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
474 #ifndef CLIB_MARCH_VARIANT
476 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
478 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
479 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
480 b->total_length_not_including_first_buffer = 0;
482 vnet_buffer (b)->tcp.flags = 0;
483 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
484 /* Leave enough space for headers */
485 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
492 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
495 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
496 u8 tcp_opts_len, tcp_hdr_opts_len;
500 wnd = tcp_window_to_advertise (tc, state);
502 /* Make and write options */
503 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
504 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
506 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
507 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
509 tcp_options_write ((u8 *) (th + 1), snd_opts);
510 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
513 tcp_zero_rwnd_sent_on (tc);
515 tcp_zero_rwnd_sent_off (tc);
519 * Convert buffer to ACK
522 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
524 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
525 TCP_EVT_DBG (TCP_EVT_ACK_SENT, tc);
526 tc->rcv_las = tc->rcv_nxt;
530 * Convert buffer to FIN-ACK
533 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
535 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
539 * Convert buffer to SYN
542 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
544 u8 tcp_hdr_opts_len, tcp_opts_len;
547 tcp_options_t snd_opts;
549 initial_wnd = tcp_initial_window_to_advertise (tc);
551 /* Make and write options */
552 clib_memset (&snd_opts, 0, sizeof (snd_opts));
553 tcp_opts_len = tcp_make_syn_options (&snd_opts, tc->rcv_wscale);
554 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
556 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
557 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
559 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
560 tcp_options_write ((u8 *) (th + 1), &snd_opts);
564 * Convert buffer to SYN-ACK
567 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
569 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
570 u8 tcp_opts_len, tcp_hdr_opts_len;
574 clib_memset (snd_opts, 0, sizeof (*snd_opts));
575 initial_wnd = tcp_initial_window_to_advertise (tc);
576 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
577 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
579 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
580 tc->rcv_nxt, tcp_hdr_opts_len,
581 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
582 tcp_options_write ((u8 *) (th + 1), snd_opts);
584 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
588 tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
589 u8 is_ip4, u32 fib_index, u8 flush)
591 vlib_main_t *vm = wrk->vm;
592 u32 *to_next, next_index;
595 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
598 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
599 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
601 /* Send to IP lookup */
602 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
603 tcp_trajectory_add_start (b, 1);
605 f = wrk->ip_lookup_tx_frames[!is_ip4];
608 f = vlib_get_frame_to_node (vm, next_index);
610 wrk->ip_lookup_tx_frames[!is_ip4] = f;
613 to_next = vlib_frame_vector_args (f);
614 to_next[f->n_vectors] = bi;
616 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
618 vlib_put_frame_to_node (vm, next_index, f);
619 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
624 tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b,
625 u32 bi, u8 is_ip4, u32 fib_index)
627 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1);
631 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
632 u8 is_ip4, u32 fib_index)
634 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0);
635 if (wrk->vm->thread_index == 0 && vlib_num_workers ())
636 session_flush_frames_main_thread (wrk->vm);
640 tcp_enqueue_to_output_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
643 u32 *to_next, next_index;
646 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
649 /* Decide where to send the packet */
650 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
651 tcp_trajectory_add_start (b, 2);
653 /* Get frame to v4/6 output node */
654 f = wrk->tx_frames[!is_ip4];
657 f = vlib_get_frame_to_node (wrk->vm, next_index);
659 wrk->tx_frames[!is_ip4] = f;
661 to_next = vlib_frame_vector_args (f);
662 to_next[f->n_vectors] = bi;
664 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
666 vlib_put_frame_to_node (wrk->vm, next_index, f);
667 wrk->tx_frames[!is_ip4] = 0;
672 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
675 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 0);
679 tcp_enqueue_to_output_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
682 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 1);
684 #endif /* CLIB_MARCH_VARIANT */
687 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
688 tcp_state_t state, u8 thread_index, u8 is_ip4)
693 ip4_address_t src_ip40, dst_ip40;
694 ip6_address_t src_ip60, dst_ip60;
695 u16 src_port, dst_port;
700 /* Find IP and TCP headers */
701 th0 = tcp_buffer_hdr (b0);
703 /* Save src and dst ip */
706 ih4 = vlib_buffer_get_current (b0);
707 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
708 src_ip40.as_u32 = ih4->src_address.as_u32;
709 dst_ip40.as_u32 = ih4->dst_address.as_u32;
713 ih6 = vlib_buffer_get_current (b0);
714 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
715 clib_memcpy_fast (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
716 clib_memcpy_fast (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
719 src_port = th0->src_port;
720 dst_port = th0->dst_port;
722 /* Try to determine what/why we're actually resetting */
723 if (state == TCP_STATE_CLOSED)
728 tmp = clib_net_to_host_u32 (th0->seq_number);
730 /* Got a SYN for no listener. */
731 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
732 ack = clib_host_to_net_u32 (tmp + 1);
737 flags = TCP_FLAG_RST;
738 seq = th0->ack_number;
742 tcp_reuse_buffer (vm, b0);
743 tcp_trajectory_add_start (b0, 4);
744 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
745 sizeof (tcp_header_t), flags, 0);
749 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
751 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
756 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
758 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
765 #ifndef CLIB_MARCH_VARIANT
767 * Send reset without reusing existing buffer
769 * It extracts connection info out of original packet
772 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
773 u32 thread_index, u8 is_ip4)
775 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
776 vlib_main_t *vm = wrk->vm;
778 u32 bi, sw_if_index, fib_index;
779 u8 tcp_hdr_len, flags = 0;
780 tcp_header_t *th, *pkt_th;
782 ip4_header_t *ih4, *pkt_ih4;
783 ip6_header_t *ih6, *pkt_ih6;
784 fib_protocol_t fib_proto;
786 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
789 b = vlib_get_buffer (vm, bi);
790 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
791 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
792 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
793 tcp_init_buffer (vm, b);
795 /* Make and write options */
796 tcp_hdr_len = sizeof (tcp_header_t);
800 pkt_ih4 = vlib_buffer_get_current (pkt);
801 pkt_th = ip4_next_header (pkt_ih4);
805 pkt_ih6 = vlib_buffer_get_current (pkt);
806 pkt_th = ip6_next_header (pkt_ih6);
809 if (tcp_ack (pkt_th))
811 flags = TCP_FLAG_RST;
812 seq = pkt_th->ack_number;
813 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
817 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
819 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
822 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
823 seq, ack, tcp_hdr_len, flags, 0);
825 /* Swap src and dst ip */
828 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
829 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
830 &pkt_ih4->src_address, IP_PROTOCOL_TCP, 1);
831 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
836 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
838 ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
839 &pkt_ih6->src_address, IP_PROTOCOL_TCP);
840 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
844 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index);
845 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
846 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
847 TCP_ERROR_RST_SENT, 1);
851 * Build and set reset packet for connection
854 tcp_send_reset (tcp_connection_t * tc)
856 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
857 vlib_main_t *vm = wrk->vm;
861 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
864 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
866 b = vlib_get_buffer (vm, bi);
867 tcp_init_buffer (vm, b);
869 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
870 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
871 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
872 flags = TCP_FLAG_RST;
873 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
874 tc->rcv_nxt, tcp_hdr_opts_len, flags,
876 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
877 ASSERT (opts_write_len == tc->snd_opts_len);
878 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
882 ih4 = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip.ip4,
883 &tc->c_rmt_ip.ip4, IP_PROTOCOL_TCP, 0);
884 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
890 ih6 = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip.ip6,
891 &tc->c_rmt_ip.ip6, IP_PROTOCOL_TCP);
892 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
895 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
896 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
897 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
898 TCP_ERROR_RST_SENT, 1);
902 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
905 tcp_header_t *th = vlib_buffer_get_current (b);
906 vlib_main_t *vm = wrk->vm;
910 ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
911 &tc->c_rmt_ip4, IP_PROTOCOL_TCP, 1);
912 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
919 ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
920 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
921 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
929 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
930 * The packet is not forwarded through tcpx_output to avoid doing lookups
931 * in the half_open pool.
934 tcp_send_syn (tcp_connection_t * tc)
936 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
937 vlib_main_t *vm = wrk->vm;
942 * Setup retransmit and establish timers before requesting buffer
943 * such that we can return if we've ran out.
945 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
946 tc->rto * TCP_TO_TIMER_TICK);
948 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
950 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
954 b = vlib_get_buffer (vm, bi);
955 tcp_init_buffer (vm, b);
956 tcp_make_syn (tc, b);
958 /* Measure RTT with this */
959 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
960 tc->rtt_seq = tc->snd_nxt;
963 tcp_push_ip_hdr (wrk, tc, b);
964 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
965 TCP_EVT_DBG (TCP_EVT_SYN_SENT, tc);
969 tcp_send_synack (tcp_connection_t * tc)
971 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
972 vlib_main_t *vm = wrk->vm;
976 tcp_retransmit_timer_force_update (tc);
978 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
980 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
984 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
985 b = vlib_get_buffer (vm, bi);
986 tcp_init_buffer (vm, b);
987 tcp_make_synack (tc, b);
988 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
989 TCP_EVT_DBG (TCP_EVT_SYNACK_SENT, tc);
993 * Flush tx frame populated by retransmits and timer pops
996 tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4)
998 if (wrk->tx_frames[!is_ip4])
1001 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
1002 vlib_put_frame_to_node (wrk->vm, next_index, wrk->tx_frames[!is_ip4]);
1003 wrk->tx_frames[!is_ip4] = 0;
1008 * Flush ip lookup tx frames populated by timer pops
1011 tcp_flush_frame_to_ip_lookup (tcp_worker_ctx_t * wrk, u8 is_ip4)
1013 if (wrk->ip_lookup_tx_frames[!is_ip4])
1016 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
1017 vlib_put_frame_to_node (wrk->vm, next_index,
1018 wrk->ip_lookup_tx_frames[!is_ip4]);
1019 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
1024 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
1027 tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk)
1029 tcp_flush_frame_to_output (wrk, 1);
1030 tcp_flush_frame_to_output (wrk, 0);
1031 tcp_flush_frame_to_ip_lookup (wrk, 1);
1032 tcp_flush_frame_to_ip_lookup (wrk, 0);
1039 tcp_send_fin (tcp_connection_t * tc)
1041 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1042 vlib_main_t *vm = wrk->vm;
1047 fin_snt = tc->flags & TCP_CONN_FINSNT;
1051 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1053 /* Out of buffers so program fin retransmit ASAP */
1054 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1058 /* Make sure retransmit retries a fin not data */
1059 tc->flags |= TCP_CONN_FINSNT;
1063 tcp_retransmit_timer_force_update (tc);
1064 b = vlib_get_buffer (vm, bi);
1065 tcp_init_buffer (vm, b);
1066 tcp_make_fin (tc, b);
1067 tcp_enqueue_to_output_now (wrk, b, bi, tc->c_is_ip4);
1068 TCP_EVT_DBG (TCP_EVT_FIN_SENT, tc);
1069 /* Account for the FIN */
1073 tc->flags |= TCP_CONN_FINSNT;
1074 tc->flags &= ~TCP_CONN_FINPNDG;
1075 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
1080 * Push TCP header and update connection variables. Should only be called
1081 * for segments with data, not for 'control' packets.
1084 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
1085 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
1087 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
1088 u32 advertise_wnd, data_len;
1089 tcp_main_t *tm = &tcp_main;
1092 data_len = b->current_length;
1093 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1094 data_len += b->total_length_not_including_first_buffer;
1096 vnet_buffer (b)->tcp.flags = 0;
1097 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
1100 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1102 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
1105 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1107 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
1109 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
1111 if (seq_geq (tc->psh_seq, snd_nxt)
1112 && seq_lt (tc->psh_seq, snd_nxt + data_len))
1113 flags |= TCP_FLAG_PSH;
1115 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
1116 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1121 clib_memcpy_fast ((u8 *) (th + 1),
1122 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1127 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1128 ASSERT (len == tc->snd_opts_len);
1132 * Update connection variables
1136 tc->snd_nxt += data_len;
1137 tc->rcv_las = tc->rcv_nxt;
1139 tc->bytes_out += data_len;
1140 tc->data_segs_out += 1;
1142 TCP_EVT_DBG (TCP_EVT_PKTIZE, tc);
1146 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
1148 tcp_connection_t *tc = (tcp_connection_t *) tconn;
1150 if (tc->flags & TCP_CONN_TRACK_BURST)
1152 tcp_bt_check_app_limited (tc);
1153 tcp_bt_track_tx (tc);
1154 tc->flags &= ~TCP_CONN_TRACK_BURST;
1157 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1158 /* update_snd_nxt */ 1);
1160 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1161 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1162 /* If not tracking an ACK, start tracking */
1163 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1165 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1166 tc->rtt_seq = tc->snd_nxt;
1168 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1170 tcp_retransmit_timer_set (tc);
1173 tcp_trajectory_add_start (b, 3);
1178 tcp_send_ack (tcp_connection_t * tc)
1180 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1181 vlib_main_t *vm = wrk->vm;
1185 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1187 tcp_update_rcv_wnd (tc);
1190 b = vlib_get_buffer (vm, bi);
1191 tcp_init_buffer (vm, b);
1192 tcp_make_ack (tc, b);
1193 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1197 tcp_program_ack (tcp_connection_t * tc)
1199 if (!(tc->flags & TCP_CONN_SNDACK))
1201 session_add_self_custom_tx_evt (&tc->connection, 1);
1202 tc->flags |= TCP_CONN_SNDACK;
1207 tcp_program_dupack (tcp_connection_t * tc)
1209 if (!(tc->flags & TCP_CONN_SNDACK))
1211 session_add_self_custom_tx_evt (&tc->connection, 1);
1212 tc->flags |= TCP_CONN_SNDACK;
1214 if (tc->pending_dupacks < 255)
1215 tc->pending_dupacks += 1;
1219 tcp_program_fastretransmit (tcp_connection_t * tc)
1221 if (!(tc->flags & TCP_CONN_FRXT_PENDING))
1223 session_add_self_custom_tx_evt (&tc->connection, 0);
1224 tc->flags |= TCP_CONN_FRXT_PENDING;
1229 * Delayed ack timer handler
1231 * Sends delayed ACK when timer expires
1234 tcp_timer_delack_handler (u32 index)
1236 u32 thread_index = vlib_get_thread_index ();
1237 tcp_connection_t *tc;
1239 tc = tcp_connection_get (index, thread_index);
1240 tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID;
1245 * Send Window Update ACK,
1246 * ensuring that it will be sent once, if RWND became non-zero,
1247 * after zero RWND has been advertised in ACK before
1250 tcp_send_window_update_ack (tcp_connection_t * tc)
1254 if (tcp_zero_rwnd_sent (tc))
1256 win = tcp_window_to_advertise (tc, tc->state);
1259 tcp_zero_rwnd_sent_off (tc);
1260 tcp_program_ack (tc);
1266 * Allocate a new buffer and build a new tcp segment
1268 * @param wrk tcp worker
1269 * @param tc connection for which the segment will be allocated
1270 * @param offset offset of the first byte in the tx fifo
1271 * @param max_deq_byte segment size
1272 * @param[out] b pointer to buffer allocated
1274 * @return the number of bytes in the segment or 0 if buffer cannot be
1275 * allocated or no data available
1278 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1279 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1281 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1282 vlib_main_t *vm = wrk->vm;
1287 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1292 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1295 * Allocate and fill in buffer(s)
1298 /* Easy case, buffer size greater than mss */
1299 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1301 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1303 *b = vlib_get_buffer (vm, bi);
1304 data = tcp_init_buffer (vm, *b);
1305 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1307 ASSERT (n_bytes == max_deq_bytes);
1308 b[0]->current_length = n_bytes;
1309 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1310 /* burst */ 0, /* update_snd_nxt */ 0);
1312 /* Split mss into multiple buffers */
1315 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1316 u16 n_peeked, len_to_deq;
1317 vlib_buffer_t *chain_b, *prev_b;
1320 /* Make sure we have enough buffers */
1321 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1322 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1323 CLIB_CACHE_LINE_BYTES);
1324 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1325 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1328 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1332 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1333 data = tcp_init_buffer (vm, *b);
1334 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1336 TRANSPORT_MAX_HDRS_LEN);
1337 b[0]->current_length = n_bytes;
1338 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1339 b[0]->total_length_not_including_first_buffer = 0;
1340 max_deq_bytes -= n_bytes;
1343 for (i = 1; i < n_bufs_per_seg; i++)
1346 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1347 chain_bi = wrk->tx_buffers[--n_bufs];
1348 chain_b = vlib_get_buffer (vm, chain_bi);
1349 chain_b->current_data = 0;
1350 data = vlib_buffer_get_current (chain_b);
1351 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1354 ASSERT (n_peeked == len_to_deq);
1355 n_bytes += n_peeked;
1356 chain_b->current_length = n_peeked;
1357 chain_b->next_buffer = 0;
1359 /* update previous buffer */
1360 prev_b->next_buffer = chain_bi;
1361 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1363 max_deq_bytes -= n_peeked;
1364 b[0]->total_length_not_including_first_buffer += n_peeked;
1367 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1368 /* burst */ 0, /* update_snd_nxt */ 0);
1370 if (PREDICT_FALSE (n_bufs))
1372 clib_warning ("not all buffers consumed");
1373 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1377 ASSERT (n_bytes > 0);
1378 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1384 * Build a retransmit segment
1386 * @return the number of bytes in the segment or 0 if there's nothing to
1390 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1391 tcp_connection_t * tc, u32 offset,
1392 u32 max_deq_bytes, vlib_buffer_t ** b)
1394 u32 start, available_bytes;
1397 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1398 ASSERT (max_deq_bytes != 0);
1401 * Make sure we can retransmit something
1403 available_bytes = transport_max_tx_dequeue (&tc->connection);
1404 ASSERT (available_bytes >= offset);
1405 available_bytes -= offset;
1406 if (!available_bytes)
1409 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1410 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1412 /* Start is beyond snd_congestion */
1413 start = tc->snd_una + offset;
1414 if (seq_geq (start, tc->snd_congestion))
1417 /* Don't overshoot snd_congestion */
1418 if (seq_gt (start + max_deq_bytes, tc->snd_congestion))
1420 max_deq_bytes = tc->snd_congestion - start;
1421 if (max_deq_bytes == 0)
1425 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1429 if (tcp_in_fastrecovery (tc))
1431 tc->snd_rxt_bytes += n_bytes;
1432 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1433 tcp_bt_track_rxt (tc, start, start + n_bytes);
1436 tc->bytes_retrans += n_bytes;
1437 tc->segs_retrans += 1;
1438 TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1443 * Reset congestion control, switch cwnd to loss window and try again.
1446 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1448 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 6);
1449 tc->prev_ssthresh = tc->ssthresh;
1450 tc->prev_cwnd = tc->cwnd;
1452 /* Clear fast recovery state if needed */
1453 if (tcp_in_fastrecovery (tc))
1454 tcp_cc_fastrecovery_clear (tc);
1456 /* Let cc algo decide loss cwnd and ssthresh */
1459 /* Start again from the beginning */
1460 tc->snd_congestion = tc->snd_nxt;
1461 tc->rcv_dupacks = 0;
1463 tc->cwnd_acc_bytes = 0;
1464 tc->tr_occurences += 1;
1465 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 2 * tc->snd_mss);
1466 tcp_recovery_on (tc);
1470 tcp_timer_retransmit_handler (u32 tc_index)
1472 u32 thread_index = vlib_get_thread_index ();
1473 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1474 vlib_main_t *vm = wrk->vm;
1475 tcp_connection_t *tc;
1476 vlib_buffer_t *b = 0;
1479 tc = tcp_connection_get (tc_index, thread_index);
1481 /* Note: the connection may have been closed and pool_put */
1482 if (PREDICT_FALSE (tc == 0 || tc->state == TCP_STATE_SYN_SENT))
1485 tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
1487 /* Wait-close and retransmit could pop at the same time */
1488 if (tc->state == TCP_STATE_CLOSED)
1491 if (tc->state >= TCP_STATE_ESTABLISHED)
1493 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1495 /* Lost FIN, retransmit and return */
1496 if (tc->flags & TCP_CONN_FINSNT)
1500 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1504 /* Shouldn't be here. This condition is tricky because it has to take
1505 * into account boff > 0 due to persist timeout. */
1506 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1507 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1508 && !tcp_flight_size (tc)))
1510 ASSERT (!tcp_in_recovery (tc));
1515 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1516 * to persist timer timeout */
1517 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1520 tcp_update_rto (tc);
1523 /* Peer is dead or network connectivity is lost. Close connection.
1524 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1525 * a min rto of 0.2s we need to retry about 8 times. */
1526 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1528 tcp_send_reset (tc);
1529 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1530 session_transport_closing_notify (&tc->connection);
1531 tcp_connection_timers_reset (tc);
1532 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
1536 /* Increment RTO backoff (also equal to number of retries) and go back
1537 * to first un-acked byte */
1540 /* TODO be less aggressive about clearing scoreboard */
1541 scoreboard_clear (&tc->sack_sb);
1543 /* First retransmit timeout */
1544 if (tc->rto_boff == 1)
1546 tcp_cc_init_rxt_timeout (tc);
1547 /* Record timestamp. Eifel detection algorithm RFC3522 */
1548 tc->snd_rxt_ts = tcp_tstamp (tc);
1551 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1552 tcp_bt_flush_samples (tc);
1554 /* If we've sent beyond snd_congestion, update it */
1555 tc->snd_congestion = seq_max (tc->snd_nxt, tc->snd_congestion);
1556 tc->snd_nxt = tc->snd_una;
1558 /* Send one segment. n_bytes may be zero due to buffer shortfall */
1559 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1562 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1566 bi = vlib_get_buffer_index (vm, b);
1567 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1569 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1570 tcp_retransmit_timer_force_update (tc);
1572 /* Retransmit SYN-ACK */
1573 else if (tc->state == TCP_STATE_SYN_RCVD)
1575 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1579 /* Passive open establish timeout */
1580 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1582 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1583 tcp_connection_timers_reset (tc);
1584 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
1588 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1590 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1595 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1596 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1598 tcp_retransmit_timer_force_update (tc);
1600 b = vlib_get_buffer (vm, bi);
1601 tcp_init_buffer (vm, b);
1602 tcp_make_synack (tc, b);
1603 TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 1);
1605 /* Retransmit timer already updated, just enqueue to output */
1606 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1610 ASSERT (tc->state == TCP_STATE_CLOSED);
1616 * SYN retransmit timer handler. Active open only.
1619 tcp_timer_retransmit_syn_handler (u32 tc_index)
1621 u32 thread_index = vlib_get_thread_index ();
1622 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1623 vlib_main_t *vm = wrk->vm;
1624 tcp_connection_t *tc;
1625 vlib_buffer_t *b = 0;
1628 tc = tcp_half_open_connection_get (tc_index);
1630 /* Note: the connection may have transitioned to ESTABLISHED... */
1631 if (PREDICT_FALSE (tc == 0 || tc->state != TCP_STATE_SYN_SENT))
1634 tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1636 /* Half-open connection actually moved to established but we were
1637 * waiting for syn retransmit to pop to call cleanup from the right
1639 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1641 if (tcp_half_open_connection_cleanup (tc))
1642 TCP_DBG ("could not remove half-open connection");
1646 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1649 /* Active open establish timeout */
1650 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1652 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
1653 tcp_connection_cleanup (tc);
1657 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1659 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1663 /* Try without increasing RTO a number of times. If this fails,
1664 * start growing RTO exponentially */
1666 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1667 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1669 b = vlib_get_buffer (vm, bi);
1670 tcp_init_buffer (vm, b);
1671 tcp_make_syn (tc, b);
1673 TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 0);
1675 /* This goes straight to ipx_lookup */
1676 tcp_push_ip_hdr (wrk, tc, b);
1677 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1679 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1680 tc->rto * TCP_TO_TIMER_TICK);
1684 * Got 0 snd_wnd from peer, try to do something about it.
1688 tcp_timer_persist_handler (u32 index)
1690 u32 thread_index = vlib_get_thread_index ();
1691 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1692 u32 bi, max_snd_bytes, available_bytes, offset;
1693 tcp_main_t *tm = vnet_get_tcp_main ();
1694 vlib_main_t *vm = wrk->vm;
1695 tcp_connection_t *tc;
1700 tc = tcp_connection_get_if_valid (index, thread_index);
1704 /* Make sure timer handle is set to invalid */
1705 tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID;
1707 /* Problem already solved or worse */
1708 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1709 || (tc->flags & TCP_CONN_FINSNT))
1712 available_bytes = transport_max_tx_dequeue (&tc->connection);
1713 offset = tc->snd_nxt - tc->snd_una;
1715 /* Reprogram persist if no new bytes available to send. We may have data
1717 if (!available_bytes)
1719 tcp_persist_timer_set (tc);
1723 if (available_bytes <= offset)
1725 ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
1729 /* Increment RTO backoff */
1731 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1734 * Try to force the first unsent segment (or buffer)
1736 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1738 tcp_persist_timer_set (tc);
1741 b = vlib_get_buffer (vm, bi);
1742 data = tcp_init_buffer (vm, b);
1744 tcp_validate_txf_size (tc, offset);
1745 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1746 max_snd_bytes = clib_min (tc->snd_mss,
1747 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1748 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1750 b->current_length = n_bytes;
1751 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1752 || tc->snd_nxt == tc->snd_una_max
1753 || tc->rto_boff > 1));
1755 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1756 /* burst */ 0, /* update_snd_nxt */ 1);
1757 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1758 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1759 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1761 /* Just sent new data, enable retransmit */
1762 tcp_retransmit_timer_update (tc);
1766 * Retransmit first unacked segment
1769 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1771 vlib_main_t *vm = wrk->vm;
1775 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 1);
1777 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1781 bi = vlib_get_buffer_index (vm, b);
1782 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1788 tcp_fast_retransmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1791 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1792 vlib_main_t *vm = wrk->vm;
1793 vlib_buffer_t *b = 0;
1795 offset = tc->snd_nxt - tc->snd_una;
1796 available_wnd = tc->snd_wnd - offset;
1797 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1799 while (n_segs < burst_size)
1801 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1805 bi = vlib_get_buffer_index (vm, b);
1806 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1807 offset += n_written;
1810 tc->snd_nxt += n_written;
1811 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1818 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1819 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1820 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1823 * Do fast retransmit with SACKs
1826 tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1829 u32 n_written = 0, offset, max_bytes, n_segs = 0, n_segs_now;
1830 sack_scoreboard_hole_t *hole;
1831 vlib_main_t *vm = wrk->vm;
1832 vlib_buffer_t *b = 0;
1833 sack_scoreboard_t *sb;
1836 u8 snd_limited = 0, can_rescue = 0;
1838 ASSERT (tcp_in_fastrecovery (tc));
1840 snd_space = tcp_available_cc_snd_space (tc);
1841 if (snd_space < tc->snd_mss)
1843 tcp_program_fastretransmit (tc);
1847 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
1849 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1851 max_deq = transport_max_tx_dequeue (&tc->connection);
1852 max_deq -= tc->snd_nxt - tc->snd_una;
1854 while (snd_space > 0 && n_segs < burst_size)
1856 hole = scoreboard_next_rxt_hole (sb, hole, max_deq, &can_rescue,
1862 snd_space = clib_min (max_deq, snd_space);
1863 burst_size = clib_min (burst_size - n_segs,
1864 snd_space / tc->snd_mss);
1865 n_segs_now = tcp_fast_retransmit_unsent (wrk, tc, burst_size);
1866 if (max_deq > n_segs_now * tc->snd_mss)
1867 tcp_program_fastretransmit (tc);
1868 n_segs += n_segs_now;
1872 if (!can_rescue || scoreboard_rescue_rxt_valid (sb, tc))
1875 /* If rescue rxt undefined or less than snd_una then one segment of
1876 * up to SMSS octets that MUST include the highest outstanding
1877 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1878 * RecoveryPoint. HighRxt MUST NOT be updated.
1880 max_bytes = clib_min (tc->snd_mss,
1881 tc->snd_congestion - tc->snd_una);
1882 max_bytes = clib_min (max_bytes, snd_space);
1883 offset = tc->snd_congestion - tc->snd_una - max_bytes;
1884 sb->rescue_rxt = tc->snd_congestion;
1885 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1890 bi = vlib_get_buffer_index (vm, b);
1891 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1896 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1897 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1901 offset = sb->high_rxt - tc->snd_una;
1902 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1904 ASSERT (n_written <= snd_space);
1906 /* Nothing left to retransmit */
1910 bi = vlib_get_buffer_index (vm, b);
1911 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1913 sb->high_rxt += n_written;
1914 snd_space -= n_written;
1919 tcp_program_fastretransmit (tc);
1926 * Fast retransmit without SACK info
1929 tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1932 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now;
1933 vlib_main_t *vm = wrk->vm;
1934 int snd_space, n_segs = 0;
1937 ASSERT (tcp_in_fastrecovery (tc));
1938 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
1940 snd_space = tcp_available_cc_snd_space (tc);
1942 if (!tcp_fastrecovery_first (tc))
1945 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1947 while (snd_space > 0 && n_segs < burst_size)
1949 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1952 /* Nothing left to retransmit */
1956 bi = vlib_get_buffer_index (vm, b);
1957 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1958 snd_space -= n_written;
1959 offset += n_written;
1963 if (n_segs == burst_size)
1968 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1969 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1972 max_deq = transport_max_tx_dequeue (&tc->connection);
1973 max_deq -= tc->snd_nxt - tc->snd_una;
1976 snd_space = clib_min (max_deq, snd_space);
1977 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1978 n_segs_now = tcp_fast_retransmit_unsent (wrk, tc, burst_size);
1979 if (max_deq > n_segs_now * tc->snd_mss)
1980 tcp_program_fastretransmit (tc);
1981 n_segs += n_segs_now;
1985 tcp_fastrecovery_first_off (tc);
1990 * Do fast retransmit
1993 tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1996 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1997 return tcp_fast_retransmit_sack (wrk, tc, burst_size);
1999 return tcp_fast_retransmit_no_sack (wrk, tc, burst_size);
2003 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
2007 if (!tc->pending_dupacks)
2013 /* If we're supposed to send dupacks but have no ooo data
2014 * send only one ack */
2015 if (!vec_len (tc->snd_sacks))
2021 /* Start with first sack block */
2022 tc->snd_sack_pos = 0;
2024 /* Generate enough dupacks to cover all sack blocks. Do not generate
2025 * more sacks than the number of packets received. But do generate at
2026 * least 3, i.e., the number needed to signal congestion, if needed. */
2027 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
2028 n_acks = clib_min (n_acks, tc->pending_dupacks);
2029 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
2030 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
2033 if (n_acks < max_burst_size)
2035 tc->pending_dupacks = 0;
2036 tc->snd_sack_pos = 0;
2037 tc->dupacks_out += n_acks;
2042 TCP_DBG ("constrained by burst size");
2043 tc->pending_dupacks = n_acks - max_burst_size;
2044 tc->dupacks_out += max_burst_size;
2045 tcp_program_dupack (tc);
2046 return max_burst_size;
2051 tcp_do_fastretransmit (tcp_connection_t * tc, u32 max_burst_size)
2053 u32 n_segs = 0, burst_size, sent_bytes, burst_bytes;
2054 tcp_worker_ctx_t *wrk;
2056 wrk = tcp_get_worker (tc->c_thread_index);
2057 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection,
2059 clib_time.last_cpu_time);
2060 burst_size = clib_min (max_burst_size, burst_bytes / tc->snd_mss);
2063 tcp_program_fastretransmit (tc);
2067 n_segs = tcp_fast_retransmit (wrk, tc, burst_size);
2068 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2069 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
2074 tcp_session_custom_tx (void *conn, u32 max_burst_size)
2076 tcp_connection_t *tc = (tcp_connection_t *) conn;
2079 if (tcp_in_fastrecovery (tc) && (tc->flags & TCP_CONN_FRXT_PENDING))
2081 tc->flags &= ~TCP_CONN_FRXT_PENDING;
2082 n_segs = tcp_do_fastretransmit (tc, max_burst_size);
2083 max_burst_size -= n_segs;
2086 if (!(tc->flags & TCP_CONN_SNDACK))
2089 tc->flags &= ~TCP_CONN_SNDACK;
2091 /* We have retransmitted packets and no dupack */
2092 if (n_segs && !tc->pending_dupacks)
2095 if (!max_burst_size)
2097 tcp_program_ack (tc);
2098 return max_burst_size;
2101 n_segs += tcp_send_acks (tc, max_burst_size);
2105 #endif /* CLIB_MARCH_VARIANT */
2108 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2109 u16 * next0, u32 * error0)
2111 ip_adjacency_t *adj;
2114 /* Not thread safe but as long as the connection exists the adj should
2116 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2118 if (ai == ADJ_INDEX_INVALID)
2120 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2121 *next0 = TCP_OUTPUT_NEXT_DROP;
2122 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2127 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2128 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2129 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2130 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2133 *next0 = TCP_OUTPUT_NEXT_DROP;
2134 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2136 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2140 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2141 u32 * to_next, u32 n_bufs)
2143 u32 n_trace = vlib_get_trace_count (vm, node);
2144 tcp_connection_t *tc;
2150 for (i = 0; i < clib_min (n_trace, n_bufs); i++)
2152 b = vlib_get_buffer (vm, to_next[i]);
2153 th = vlib_buffer_get_current (b);
2154 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2156 t = vlib_add_trace (vm, node, b, sizeof (*t));
2157 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2158 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2163 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2164 tcp_connection_t * tc0, u8 is_ip4)
2166 tcp_header_t *th0 = 0;
2168 th0 = vlib_buffer_get_current (b0);
2169 TCP_EVT_DBG (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length);
2172 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2173 IP_PROTOCOL_TCP, 1);
2174 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
2175 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
2181 ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6,
2182 &tc0->c_rmt_ip6, IP_PROTOCOL_TCP);
2183 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
2184 vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data;
2185 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
2191 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2192 u32 * error0, u16 * next0, u8 is_ip4)
2195 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2197 *error0 = TCP_ERROR_INVALID_CONNECTION;
2198 *next0 = TCP_OUTPUT_NEXT_DROP;
2202 /* If next_index is not drop use it */
2203 if (tc0->next_node_index)
2205 *next0 = tc0->next_node_index;
2206 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2209 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2210 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2214 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2215 tcp_output_handle_link_local (tc0, b0, next0, error0);
2218 if (!TCP_ALWAYS_ACK)
2219 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
2225 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2226 vlib_frame_t * frame, int is_ip4)
2228 u32 n_left_from, *from, thread_index = vm->thread_index;
2229 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2230 u16 nexts[VLIB_FRAME_SIZE], *next;
2232 from = vlib_frame_vector_args (frame);
2233 n_left_from = frame->n_vectors;
2234 tcp_set_time_now (tcp_get_worker (thread_index));
2236 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2237 tcp46_output_trace_frame (vm, node, from, n_left_from);
2239 vlib_get_buffers (vm, from, bufs, n_left_from);
2243 while (n_left_from >= 4)
2245 u32 error0 = TCP_ERROR_PKTS_SENT, error1 = TCP_ERROR_PKTS_SENT;
2246 tcp_connection_t *tc0, *tc1;
2249 vlib_prefetch_buffer_header (b[2], STORE);
2250 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2252 vlib_prefetch_buffer_header (b[3], STORE);
2253 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2256 next[0] = next[1] = TCP_OUTPUT_NEXT_IP_LOOKUP;
2258 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2260 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2263 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2264 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2266 tcp_output_handle_packet (tc0, b[0], &error0, &next[0], is_ip4);
2267 tcp_output_handle_packet (tc1, b[1], &error1, &next[1], is_ip4);
2273 while (n_left_from > 0)
2275 u32 error0 = TCP_ERROR_PKTS_SENT;
2276 tcp_connection_t *tc0;
2278 if (n_left_from > 1)
2280 vlib_prefetch_buffer_header (b[1], STORE);
2281 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2284 next[0] = TCP_OUTPUT_NEXT_IP_LOOKUP;
2285 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2288 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2289 tcp_output_handle_packet (tc0, b[0], &error0, &next[0], is_ip4);
2296 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2297 return frame->n_vectors;
2300 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2301 vlib_frame_t * from_frame)
2303 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2306 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2307 vlib_frame_t * from_frame)
2309 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2313 VLIB_REGISTER_NODE (tcp4_output_node) =
2315 .name = "tcp4-output",
2316 /* Takes a vector of packets. */
2317 .vector_size = sizeof (u32),
2318 .n_errors = TCP_N_ERROR,
2319 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2320 .error_strings = tcp_error_strings,
2321 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2323 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2324 foreach_tcp4_output_next
2327 .format_buffer = format_tcp_header,
2328 .format_trace = format_tcp_tx_trace,
2333 VLIB_REGISTER_NODE (tcp6_output_node) =
2335 .name = "tcp6-output",
2336 /* Takes a vector of packets. */
2337 .vector_size = sizeof (u32),
2338 .n_errors = TCP_N_ERROR,
2339 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2340 .error_strings = tcp_error_strings,
2341 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2343 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2344 foreach_tcp6_output_next
2347 .format_buffer = format_tcp_header,
2348 .format_trace = format_tcp_tx_trace,
2352 typedef enum _tcp_reset_next
2354 TCP_RESET_NEXT_DROP,
2355 TCP_RESET_NEXT_IP_LOOKUP,
2359 #define foreach_tcp4_reset_next \
2360 _(DROP, "error-drop") \
2361 _(IP_LOOKUP, "ip4-lookup")
2363 #define foreach_tcp6_reset_next \
2364 _(DROP, "error-drop") \
2365 _(IP_LOOKUP, "ip6-lookup")
2368 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2369 vlib_frame_t * from_frame, u8 is_ip4)
2371 u32 n_left_from, next_index, *from, *to_next;
2372 u32 my_thread_index = vm->thread_index;
2374 from = vlib_frame_vector_args (from_frame);
2375 n_left_from = from_frame->n_vectors;
2377 next_index = node->cached_next_index;
2379 while (n_left_from > 0)
2383 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2385 while (n_left_from > 0 && n_left_to_next > 0)
2391 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2398 n_left_to_next -= 1;
2400 b0 = vlib_get_buffer (vm, bi0);
2402 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2403 my_thread_index, is_ip4))
2405 error0 = TCP_ERROR_LOOKUP_DROPS;
2406 next0 = TCP_RESET_NEXT_DROP;
2410 /* Prepare to send to IP lookup */
2411 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2412 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2415 b0->error = node->errors[error0];
2416 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2417 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2419 th0 = vlib_buffer_get_current (b0);
2421 th0 = ip4_next_header ((ip4_header_t *) th0);
2423 th0 = ip6_next_header ((ip6_header_t *) th0);
2424 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2425 clib_memcpy_fast (&t0->tcp_header, th0,
2426 sizeof (t0->tcp_header));
2429 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2430 n_left_to_next, bi0, next0);
2432 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2434 return from_frame->n_vectors;
2437 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2438 vlib_frame_t * from_frame)
2440 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2443 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2444 vlib_frame_t * from_frame)
2446 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2450 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2451 .name = "tcp4-reset",
2452 .vector_size = sizeof (u32),
2453 .n_errors = TCP_N_ERROR,
2454 .error_strings = tcp_error_strings,
2455 .n_next_nodes = TCP_RESET_N_NEXT,
2457 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2458 foreach_tcp4_reset_next
2461 .format_trace = format_tcp_tx_trace,
2466 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2467 .name = "tcp6-reset",
2468 .vector_size = sizeof (u32),
2469 .n_errors = TCP_N_ERROR,
2470 .error_strings = tcp_error_strings,
2471 .n_next_nodes = TCP_RESET_N_NEXT,
2473 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2474 foreach_tcp6_reset_next
2477 .format_trace = format_tcp_tx_trace,
2482 * fd.io coding-style-patch-verification: ON
2485 * eval: (c-set-style "gnu")