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 <vppinfra/sparse_vec.h>
17 #include <vnet/fib/ip4_fib.h>
18 #include <vnet/fib/ip6_fib.h>
19 #include <vnet/tcp/tcp_packet.h>
20 #include <vnet/tcp/tcp.h>
21 #include <vnet/session/session.h>
24 static char *tcp_error_strings[] = {
25 #define tcp_error(n,s) s,
26 #include <vnet/tcp/tcp_error.def>
30 /* All TCP nodes have the same outgoing arcs */
31 #define foreach_tcp_state_next \
32 _ (DROP4, "ip4-drop") \
33 _ (DROP6, "ip6-drop") \
34 _ (TCP4_OUTPUT, "tcp4-output") \
35 _ (TCP6_OUTPUT, "tcp6-output")
37 typedef enum _tcp_established_next
39 #define _(s,n) TCP_ESTABLISHED_NEXT_##s,
40 foreach_tcp_state_next
42 TCP_ESTABLISHED_N_NEXT,
43 } tcp_established_next_t;
45 typedef enum _tcp_rcv_process_next
47 #define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
48 foreach_tcp_state_next
50 TCP_RCV_PROCESS_N_NEXT,
51 } tcp_rcv_process_next_t;
53 typedef enum _tcp_syn_sent_next
55 #define _(s,n) TCP_SYN_SENT_NEXT_##s,
56 foreach_tcp_state_next
59 } tcp_syn_sent_next_t;
61 typedef enum _tcp_listen_next
63 #define _(s,n) TCP_LISTEN_NEXT_##s,
64 foreach_tcp_state_next
69 /* Generic, state independent indices */
70 typedef enum _tcp_state_next
72 #define _(s,n) TCP_NEXT_##s,
73 foreach_tcp_state_next
78 #define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
79 : TCP_NEXT_TCP6_OUTPUT)
81 #define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
85 * Validate segment sequence number. As per RFC793:
87 * Segment Receive Test
89 * ------- ------- -------------------------------------------
90 * 0 0 SEG.SEQ = RCV.NXT
91 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
93 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
94 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
96 * This ultimately consists in checking if segment falls within the window.
97 * The one important difference compared to RFC793 is that we use rcv_las,
98 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
99 * peer's reference when computing our receive window.
102 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
103 * however, is too strict when we have retransmits. Instead we just check that
104 * the seq is not beyond the right edge and that the end of the segment is not
105 * less than the left edge.
107 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
108 * use rcv_nxt in the right edge window test instead of rcv_las.
112 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
114 return (seq_geq (end_seq, tc->rcv_las)
115 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
119 * Parse TCP header options.
121 * @param th TCP header
122 * @param to TCP options data structure to be populated
123 * @param is_syn set if packet is syn
124 * @return -1 if parsing failed
127 tcp_options_parse (tcp_header_t * th, tcp_options_t * to, u8 is_syn)
130 u8 opt_len, opts_len, kind;
134 opts_len = (tcp_doff (th) << 2) - sizeof (tcp_header_t);
135 data = (const u8 *) (th + 1);
137 /* Zero out all flags but those set in SYN */
138 to->flags &= (TCP_OPTS_FLAG_SACK_PERMITTED | TCP_OPTS_FLAG_WSCALE
139 | TCP_OPTS_FLAG_TSTAMP | TCP_OPTS_FLAG_MSS);
141 for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
145 /* Get options length */
146 if (kind == TCP_OPTION_EOL)
148 else if (kind == TCP_OPTION_NOOP)
160 /* weird option length */
161 if (opt_len < 2 || opt_len > opts_len)
171 if ((opt_len == TCP_OPTION_LEN_MSS) && tcp_syn (th))
173 to->flags |= TCP_OPTS_FLAG_MSS;
174 to->mss = clib_net_to_host_u16 (*(u16 *) (data + 2));
177 case TCP_OPTION_WINDOW_SCALE:
180 if ((opt_len == TCP_OPTION_LEN_WINDOW_SCALE) && tcp_syn (th))
182 to->flags |= TCP_OPTS_FLAG_WSCALE;
183 to->wscale = data[2];
184 if (to->wscale > TCP_MAX_WND_SCALE)
185 to->wscale = TCP_MAX_WND_SCALE;
188 case TCP_OPTION_TIMESTAMP:
190 to->flags |= TCP_OPTS_FLAG_TSTAMP;
191 if ((to->flags & TCP_OPTS_FLAG_TSTAMP)
192 && opt_len == TCP_OPTION_LEN_TIMESTAMP)
194 to->tsval = clib_net_to_host_u32 (*(u32 *) (data + 2));
195 to->tsecr = clib_net_to_host_u32 (*(u32 *) (data + 6));
198 case TCP_OPTION_SACK_PERMITTED:
201 if (opt_len == TCP_OPTION_LEN_SACK_PERMITTED && tcp_syn (th))
202 to->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
204 case TCP_OPTION_SACK_BLOCK:
205 /* If SACK permitted was not advertised or a SYN, break */
206 if ((to->flags & TCP_OPTS_FLAG_SACK_PERMITTED) == 0 || tcp_syn (th))
209 /* If too short or not correctly formatted, break */
210 if (opt_len < 10 || ((opt_len - 2) % TCP_OPTION_LEN_SACK_BLOCK))
213 to->flags |= TCP_OPTS_FLAG_SACK;
214 to->n_sack_blocks = (opt_len - 2) / TCP_OPTION_LEN_SACK_BLOCK;
215 vec_reset_length (to->sacks);
216 for (j = 0; j < to->n_sack_blocks; j++)
218 b.start = clib_net_to_host_u32 (*(u32 *) (data + 2 + 8 * j));
219 b.end = clib_net_to_host_u32 (*(u32 *) (data + 6 + 8 * j));
220 vec_add1 (to->sacks, b);
224 /* Nothing to see here */
232 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
233 * timestamp to echo and it's less than tsval_recent, drop segment
234 * but still send an ACK in order to retain TCP's mechanism for detecting
235 * and recovering from half-open connections
237 * Or at least that's what the theory says. It seems that this might not work
238 * very well with packet reordering and fast retransmit. XXX
241 tcp_segment_check_paws (tcp_connection_t * tc)
243 return tcp_opts_tstamp (&tc->rcv_opts)
244 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
248 * Update tsval recent
251 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
254 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
255 * of an incoming segment:
256 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
257 * then the TSval from the segment is copied to TS.Recent;
258 * otherwise, the TSval is ignored.
260 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
261 && seq_leq (tc->rcv_las, seq_end))
263 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
264 tc->tsval_recent = tc->rcv_opts.tsval;
265 tc->tsval_recent_age = tcp_time_now_w_thread (tc->c_thread_index);
270 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
272 * It first verifies if segment has a wrapped sequence number (PAWS) and then
273 * does the processing associated to the first four steps (ignoring security
274 * and precedence): sequence number, rst bit and syn bit checks.
276 * @return 0 if segments passes validation.
279 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
280 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
282 /* We could get a burst of RSTs interleaved with acks */
283 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
285 tcp_send_reset (tc0);
286 *error0 = TCP_ERROR_CONNECTION_CLOSED;
290 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
292 *error0 = TCP_ERROR_SEGMENT_INVALID;
296 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
298 *error0 = TCP_ERROR_OPTIONS;
302 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
304 *error0 = TCP_ERROR_PAWS;
305 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
306 vnet_buffer (b0)->tcp.seq_end);
308 /* If it just so happens that a segment updates tsval_recent for a
309 * segment over 24 days old, invalidate tsval_recent. */
310 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
311 tcp_time_now_w_thread (tc0->c_thread_index)))
313 tc0->tsval_recent = tc0->rcv_opts.tsval;
314 clib_warning ("paws failed: 24-day old segment");
316 /* Drop after ack if not rst. Resets can fail paws check as per
317 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
318 * be subjected to the PAWS check by verifying an acceptable value in
320 else if (!tcp_rst (th0))
322 tcp_program_ack (tc0);
323 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
328 /* 1st: check sequence number */
329 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
330 vnet_buffer (b0)->tcp.seq_end))
332 /* SYN/SYN-ACK retransmit */
334 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
336 tcp_options_parse (th0, &tc0->rcv_opts, 1);
337 if (tc0->state == TCP_STATE_SYN_RCVD)
339 tcp_send_synack (tc0);
340 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
341 *error0 = TCP_ERROR_SYNS_RCVD;
345 tcp_program_ack (tc0);
346 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
347 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
352 /* If our window is 0 and the packet is in sequence, let it pass
353 * through for ack processing. It should be dropped later. */
354 if (tc0->rcv_wnd < tc0->snd_mss
355 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
358 /* If we entered recovery and peer did so as well, there's a chance that
359 * dup acks won't be acceptable on either end because seq_end may be less
360 * than rcv_las. This can happen if acks are lost in both directions. */
361 if (tcp_in_recovery (tc0)
362 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
363 tc0->rcv_las - tc0->rcv_wnd)
364 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
365 tc0->rcv_nxt + tc0->rcv_wnd))
368 *error0 = TCP_ERROR_RCV_WND;
370 /* If we advertised a zero rcv_wnd and the segment is in the past or the
371 * next one that we expect, it is probably a window probe */
372 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
373 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
374 tc0->rcv_las + tc0->rcv_opts.mss))
375 *error0 = TCP_ERROR_ZERO_RWND;
377 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
380 /* If not RST, send dup ack */
383 tcp_program_dupack (tc0);
384 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
392 /* 2nd: check the RST bit */
393 if (PREDICT_FALSE (tcp_rst (th0)))
395 tcp_connection_reset (tc0);
396 *error0 = TCP_ERROR_RST_RCVD;
400 /* 3rd: check security and precedence (skip) */
402 /* 4th: check the SYN bit (in window) */
403 if (PREDICT_FALSE (tcp_syn (th0)))
405 /* As per RFC5961 send challenge ack instead of reset */
406 tcp_program_ack (tc0);
407 *error0 = TCP_ERROR_SPURIOUS_SYN;
411 /* If segment in window, save timestamp */
412 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
413 vnet_buffer (b0)->tcp.seq_end);
421 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
423 /* SND.UNA =< SEG.ACK =< SND.NXT */
424 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
425 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
427 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
428 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
430 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
433 *error = TCP_ERROR_ACK_INVALID;
438 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
439 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
440 *error = TCP_ERROR_ACK_OK;
445 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
447 * Note that although the original article, srtt and rttvar are scaled
448 * to minimize round-off errors, here we don't. Instead, we rely on
449 * better precision time measurements.
451 * TODO support us rtt resolution
454 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
460 err = mrtt - tc->srtt;
462 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
463 * The increase should be bound */
464 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
465 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
466 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
470 /* First measurement. */
472 tc->rttvar = mrtt >> 1;
476 #ifndef CLIB_MARCH_VARIANT
478 tcp_update_rto (tcp_connection_t * tc)
480 tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
481 tc->rto = clib_max (tc->rto, TCP_RTO_MIN);
483 #endif /* CLIB_MARCH_VARIANT */
486 * Update RTT estimate and RTO timer
488 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
489 * timing. Middle boxes are known to fiddle with TCP options so we
490 * should give higher priority to ACK timing.
492 * This should be called only if previously sent bytes have been acked.
494 * return 1 if valid rtt 0 otherwise
497 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
501 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
502 * RTT because they're ambiguous. */
503 if (tcp_in_cong_recovery (tc))
505 /* Accept rtt estimates for samples that have not been retransmitted */
506 if ((tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
507 && !(rs->flags & TCP_BTS_IS_RXT))
509 mrtt = rs->rtt_time * THZ;
515 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
517 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
518 tc->mrtt_us = tc->mrtt_us + (sample - tc->mrtt_us) * 0.125;
519 mrtt = clib_max ((u32) (sample * THZ), 1);
520 /* Allow measuring of a new RTT */
523 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
524 * snd_una, i.e., the left side of the send window:
525 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
526 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
528 u32 now = tcp_tstamp (tc);
529 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
534 /* Ignore dubious measurements */
535 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
538 tcp_estimate_rtt (tc, mrtt);
542 /* If we got here something must've been ACKed so make sure boff is 0,
543 * even if mrtt is not valid since we update the rto lower */
551 tcp_estimate_initial_rtt (tcp_connection_t * tc)
553 u8 thread_index = vlib_num_workers ()? 1 : 0;
558 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
559 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
560 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
565 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
566 mrtt = clib_max (mrtt, 1);
567 /* Due to retransmits we don't know the initial mrtt */
568 if (tc->rto_boff && mrtt > 1 * THZ)
570 tc->mrtt_us = (f64) mrtt *TCP_TICK;
573 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
574 tcp_estimate_rtt (tc, mrtt);
579 tcp_recovery_no_snd_space (tcp_connection_t * tc)
581 return (tcp_in_fastrecovery (tc)
582 && tcp_fastrecovery_prr_snd_space (tc) < tc->snd_mss)
583 || (tcp_in_recovery (tc)
584 && tcp_available_output_snd_space (tc) < tc->snd_mss);
588 * Dequeue bytes for connections that have received acks in last burst
591 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
593 u32 thread_index = wrk->vm->thread_index;
594 u32 *pending_deq_acked;
595 tcp_connection_t *tc;
598 if (!vec_len (wrk->pending_deq_acked))
601 pending_deq_acked = wrk->pending_deq_acked;
602 for (i = 0; i < vec_len (pending_deq_acked); i++)
604 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
605 tc->flags &= ~TCP_CONN_DEQ_PENDING;
609 /* Dequeue the newly ACKed bytes */
610 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
612 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
614 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
616 if (seq_leq (tc->psh_seq, tc->snd_una))
617 tc->flags &= ~TCP_CONN_PSH_PENDING;
620 /* If everything has been acked, stop retransmit timer
621 * otherwise update. */
622 tcp_retransmit_timer_update (tc);
624 /* Update pacer based on our new cwnd estimate */
625 tcp_connection_tx_pacer_update (tc);
628 /* Reset the pacer if we've been idle, i.e., no data sent or if
629 * we're in recovery and snd space constrained */
630 if (tc->data_segs_out == tc->prev_dsegs_out
631 || tcp_recovery_no_snd_space (tc))
632 transport_connection_tx_pacer_reset_bucket (&tc->connection);
633 tc->prev_dsegs_out = tc->data_segs_out;
635 _vec_len (wrk->pending_deq_acked) = 0;
639 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
641 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
643 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
644 tc->flags |= TCP_CONN_DEQ_PENDING;
646 tc->burst_acked += tc->bytes_acked;
649 #ifndef CLIB_MARCH_VARIANT
651 scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
653 ASSERT (!pool_is_free_index (sb->holes, hole - sb->holes));
654 return hole - sb->holes;
658 scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
660 return hole->end - hole->start;
663 sack_scoreboard_hole_t *
664 scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
666 if (index != TCP_INVALID_SACK_HOLE_INDEX)
667 return pool_elt_at_index (sb->holes, index);
671 sack_scoreboard_hole_t *
672 scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
674 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
675 return pool_elt_at_index (sb->holes, hole->next);
679 sack_scoreboard_hole_t *
680 scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
682 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
683 return pool_elt_at_index (sb->holes, hole->prev);
687 sack_scoreboard_hole_t *
688 scoreboard_first_hole (sack_scoreboard_t * sb)
690 if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
691 return pool_elt_at_index (sb->holes, sb->head);
695 sack_scoreboard_hole_t *
696 scoreboard_last_hole (sack_scoreboard_t * sb)
698 if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
699 return pool_elt_at_index (sb->holes, sb->tail);
704 scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
706 sack_scoreboard_hole_t *next, *prev;
708 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
710 next = pool_elt_at_index (sb->holes, hole->next);
711 next->prev = hole->prev;
715 sb->tail = hole->prev;
718 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
720 prev = pool_elt_at_index (sb->holes, hole->prev);
721 prev->next = hole->next;
725 sb->head = hole->next;
728 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
729 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
731 /* Poison the entry */
733 clib_memset (hole, 0xfe, sizeof (*hole));
735 pool_put (sb->holes, hole);
738 static sack_scoreboard_hole_t *
739 scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
742 sack_scoreboard_hole_t *hole, *next, *prev;
745 pool_get (sb->holes, hole);
746 clib_memset (hole, 0, sizeof (*hole));
750 hole_index = scoreboard_hole_index (sb, hole);
752 prev = scoreboard_get_hole (sb, prev_index);
755 hole->prev = prev_index;
756 hole->next = prev->next;
758 if ((next = scoreboard_next_hole (sb, hole)))
759 next->prev = hole_index;
761 sb->tail = hole_index;
763 prev->next = hole_index;
767 sb->head = hole_index;
768 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
769 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
776 scoreboard_update_sacked_rxt (sack_scoreboard_t * sb, u32 start, u32 end,
779 if (!has_rxt || seq_geq (start, sb->high_rxt))
783 seq_lt (end, sb->high_rxt) ? (end - start) : (sb->high_rxt - start);
787 scoreboard_update_bytes (sack_scoreboard_t * sb, u32 ack, u32 snd_mss)
789 sack_scoreboard_hole_t *left, *right;
790 u32 sacked = 0, blks = 0, old_sacked;
792 old_sacked = sb->sacked_bytes;
794 sb->last_lost_bytes = 0;
796 sb->sacked_bytes = 0;
798 right = scoreboard_last_hole (sb);
801 sb->sacked_bytes = sb->high_sacked - ack;
805 if (seq_gt (sb->high_sacked, right->end))
807 sacked = sb->high_sacked - right->end;
811 while (sacked < (TCP_DUPACK_THRESHOLD - 1) * snd_mss
812 && blks < TCP_DUPACK_THRESHOLD)
815 sb->lost_bytes += scoreboard_hole_bytes (right);
817 left = scoreboard_prev_hole (sb, right);
820 ASSERT (right->start == ack || sb->is_reneging);
821 sacked += right->start - ack;
826 sacked += right->start - left->end;
831 /* right is first lost */
834 sb->lost_bytes += scoreboard_hole_bytes (right);
835 sb->last_lost_bytes += right->is_lost ? 0 : (right->end - right->start);
837 left = scoreboard_prev_hole (sb, right);
840 ASSERT (right->start == ack || sb->is_reneging);
841 sacked += right->start - ack;
844 sacked += right->start - left->end;
848 sb->sacked_bytes = sacked;
849 sb->last_sacked_bytes = sacked - (old_sacked - sb->last_bytes_delivered);
853 * Figure out the next hole to retransmit
855 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
857 sack_scoreboard_hole_t *
858 scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
859 sack_scoreboard_hole_t * start,
860 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
862 sack_scoreboard_hole_t *hole = 0;
864 hole = start ? start : scoreboard_first_hole (sb);
865 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
866 hole = scoreboard_next_hole (sb, hole);
868 /* Nothing, return */
871 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
875 /* Rule (1): if higher than rxt, less than high_sacked and lost */
876 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
878 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
882 /* Rule (2): available unsent data */
885 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
888 /* Rule (3): if hole not lost */
889 else if (seq_lt (hole->start, sb->high_sacked))
891 /* And we didn't already retransmit it */
892 if (seq_leq (hole->end, sb->high_rxt))
894 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
898 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
900 /* Rule (4): if hole beyond high_sacked */
903 ASSERT (seq_geq (hole->start, sb->high_sacked));
906 /* HighRxt MUST NOT be updated */
911 if (hole && seq_lt (sb->high_rxt, hole->start))
912 sb->high_rxt = hole->start;
918 scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una)
920 sack_scoreboard_hole_t *hole;
921 hole = scoreboard_first_hole (sb);
924 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
925 sb->cur_rxt_hole = sb->head;
927 sb->high_rxt = snd_una;
928 sb->rescue_rxt = snd_una - 1;
932 scoreboard_init (sack_scoreboard_t * sb)
934 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
935 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
936 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
940 scoreboard_clear (sack_scoreboard_t * sb)
942 sack_scoreboard_hole_t *hole;
943 while ((hole = scoreboard_first_hole (sb)))
945 scoreboard_remove_hole (sb, hole);
947 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
948 ASSERT (pool_elts (sb->holes) == 0);
949 sb->sacked_bytes = 0;
950 sb->last_sacked_bytes = 0;
951 sb->last_bytes_delivered = 0;
953 sb->last_lost_bytes = 0;
954 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
959 scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end)
961 sack_scoreboard_hole_t *last_hole;
963 clib_warning ("sack reneging");
965 scoreboard_clear (sb);
966 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
968 last_hole->is_lost = 1;
969 sb->tail = scoreboard_hole_index (sb, last_hole);
970 sb->high_sacked = start;
971 scoreboard_init_rxt (sb, start);
974 #endif /* CLIB_MARCH_VARIANT */
977 * Test that scoreboard is sane after recovery
979 * Returns 1 if scoreboard is empty or if first hole beyond
983 tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
985 sack_scoreboard_hole_t *hole;
986 hole = scoreboard_first_hole (&tc->sack_sb);
987 return (!hole || (seq_geq (hole->start, tc->snd_una)
988 && seq_lt (hole->end, tc->snd_nxt)));
991 #ifndef CLIB_MARCH_VARIANT
994 tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
996 sack_scoreboard_hole_t *hole, *next_hole;
997 sack_scoreboard_t *sb = &tc->sack_sb;
998 sack_block_t *blk, *rcv_sacks;
999 u32 blk_index = 0, i, j;
1002 sb->last_sacked_bytes = 0;
1003 sb->last_bytes_delivered = 0;
1006 if (!tcp_opts_sack (&tc->rcv_opts)
1007 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1010 has_rxt = tcp_in_cong_recovery (tc);
1012 /* Remove invalid blocks */
1013 blk = tc->rcv_opts.sacks;
1014 while (blk < vec_end (tc->rcv_opts.sacks))
1016 if (seq_lt (blk->start, blk->end)
1017 && seq_gt (blk->start, tc->snd_una)
1018 && seq_gt (blk->start, ack)
1019 && seq_lt (blk->start, tc->snd_nxt)
1020 && seq_leq (blk->end, tc->snd_nxt))
1025 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
1028 /* Add block for cumulative ack */
1029 if (seq_gt (ack, tc->snd_una))
1031 vec_add2 (tc->rcv_opts.sacks, blk, 1);
1032 blk->start = tc->snd_una;
1036 if (vec_len (tc->rcv_opts.sacks) == 0)
1039 tcp_scoreboard_trace_add (tc, ack);
1041 /* Make sure blocks are ordered */
1042 rcv_sacks = tc->rcv_opts.sacks;
1043 for (i = 0; i < vec_len (rcv_sacks); i++)
1044 for (j = i + 1; j < vec_len (rcv_sacks); j++)
1045 if (seq_lt (rcv_sacks[j].start, rcv_sacks[i].start))
1047 sack_block_t tmp = rcv_sacks[i];
1048 rcv_sacks[i] = rcv_sacks[j];
1052 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1054 /* Handle reneging as a special case */
1055 if (PREDICT_FALSE (sb->is_reneging))
1057 /* No holes, only sacked bytes */
1058 if (seq_leq (tc->snd_nxt, sb->high_sacked))
1060 /* No progress made so return */
1061 if (seq_leq (ack, tc->snd_una))
1064 /* Update sacked bytes delivered and return */
1065 sb->last_bytes_delivered = ack - tc->snd_una;
1066 sb->sacked_bytes -= sb->last_bytes_delivered;
1067 sb->is_reneging = seq_lt (ack, sb->high_sacked);
1071 /* New hole above high sacked. Add it and process normally */
1072 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1073 sb->high_sacked, tc->snd_nxt);
1074 sb->tail = scoreboard_hole_index (sb, hole);
1076 /* Not reneging and no holes. Insert the first that covers all
1077 * outstanding bytes */
1080 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1081 tc->snd_una, tc->snd_nxt);
1082 sb->tail = scoreboard_hole_index (sb, hole);
1084 sb->high_sacked = rcv_sacks[vec_len (rcv_sacks) - 1].end;
1088 /* If we have holes but snd_nxt is beyond the last hole, update
1089 * last hole end or add new hole after high sacked */
1090 hole = scoreboard_last_hole (sb);
1091 if (seq_gt (tc->snd_nxt, hole->end))
1093 if (seq_geq (hole->start, sb->high_sacked))
1095 hole->end = tc->snd_nxt;
1097 /* New hole after high sacked block */
1098 else if (seq_lt (sb->high_sacked, tc->snd_nxt))
1100 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
1105 /* Keep track of max byte sacked for when the last hole
1107 sb->high_sacked = seq_max (rcv_sacks[vec_len (rcv_sacks) - 1].end,
1111 /* Walk the holes with the SACK blocks */
1112 hole = pool_elt_at_index (sb->holes, sb->head);
1114 if (PREDICT_FALSE (sb->is_reneging))
1115 sb->last_bytes_delivered += hole->start - tc->snd_una;
1117 while (hole && blk_index < vec_len (rcv_sacks))
1119 blk = &rcv_sacks[blk_index];
1120 if (seq_leq (blk->start, hole->start))
1122 /* Block covers hole. Remove hole */
1123 if (seq_geq (blk->end, hole->end))
1125 next_hole = scoreboard_next_hole (sb, hole);
1127 /* If covered by ack, compute delivered bytes */
1128 if (blk->end == ack)
1130 u32 sacked = next_hole ? next_hole->start : sb->high_sacked;
1131 if (PREDICT_FALSE (seq_lt (ack, sacked)))
1133 sb->last_bytes_delivered += ack - hole->end;
1134 sb->is_reneging = 1;
1138 sb->last_bytes_delivered += sacked - hole->end;
1139 sb->is_reneging = 0;
1142 scoreboard_update_sacked_rxt (sb, hole->start, hole->end,
1144 scoreboard_remove_hole (sb, hole);
1147 /* Partial 'head' overlap */
1150 if (seq_gt (blk->end, hole->start))
1152 scoreboard_update_sacked_rxt (sb, hole->start, blk->end,
1154 hole->start = blk->end;
1161 /* Hole must be split */
1162 if (seq_lt (blk->end, hole->end))
1164 u32 hole_index = scoreboard_hole_index (sb, hole);
1165 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1167 /* Pool might've moved */
1168 hole = scoreboard_get_hole (sb, hole_index);
1169 hole->end = blk->start;
1171 scoreboard_update_sacked_rxt (sb, blk->start, blk->end,
1175 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
1177 else if (seq_lt (blk->start, hole->end))
1179 scoreboard_update_sacked_rxt (sb, blk->start, hole->end,
1181 hole->end = blk->start;
1183 hole = scoreboard_next_hole (sb, hole);
1187 scoreboard_update_bytes (sb, ack, tc->snd_mss);
1189 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
1190 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
1191 || sb->sacked_bytes <= tc->snd_nxt - seq_max (tc->snd_una, ack));
1192 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_nxt
1193 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
1194 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1195 || sb->is_reneging || sb->holes[sb->head].start == ack);
1196 ASSERT (sb->last_lost_bytes <= sb->lost_bytes);
1197 ASSERT ((ack - tc->snd_una) + sb->last_sacked_bytes
1198 - sb->last_bytes_delivered >= sb->rxt_sacked);
1199 ASSERT ((ack - tc->snd_una) >= tc->sack_sb.last_bytes_delivered
1200 || (tc->flags & TCP_CONN_FINSNT));
1202 TCP_EVT (TCP_EVT_CC_SCOREBOARD, tc);
1204 #endif /* CLIB_MARCH_VARIANT */
1207 * Try to update snd_wnd based on feedback received from peer.
1209 * If successful, and new window is 'effectively' 0, activate persist
1213 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1215 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1216 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
1217 if (seq_lt (tc->snd_wl1, seq)
1218 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
1220 tc->snd_wnd = snd_wnd;
1223 TCP_EVT (TCP_EVT_SND_WND, tc);
1225 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
1227 /* Set persist timer if not set and we just got 0 wnd */
1228 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1229 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
1230 tcp_persist_timer_set (tc);
1234 tcp_persist_timer_reset (tc);
1235 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
1238 tcp_update_rto (tc);
1245 * Init loss recovery/fast recovery.
1247 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1248 * updated in @ref tcp_cc_handle_event after fast retransmit
1251 tcp_cc_init_congestion (tcp_connection_t * tc)
1253 tcp_fastrecovery_on (tc);
1254 tc->snd_congestion = tc->snd_nxt;
1255 tc->cwnd_acc_bytes = 0;
1256 tc->snd_rxt_bytes = 0;
1257 tc->rxt_delivered = 0;
1258 tc->prr_delivered = 0;
1259 tc->prr_start = tc->snd_una;
1260 tc->prev_ssthresh = tc->ssthresh;
1261 tc->prev_cwnd = tc->cwnd;
1263 tc->snd_rxt_ts = tcp_tstamp (tc);
1264 tcp_cc_congestion (tc);
1266 /* Post retransmit update cwnd to ssthresh and account for the
1267 * three segments that have left the network and should've been
1268 * buffered at the receiver XXX */
1269 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
1270 tc->cwnd += 3 * tc->snd_mss;
1272 tc->fr_occurences += 1;
1273 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
1277 tcp_cc_congestion_undo (tcp_connection_t * tc)
1279 tc->cwnd = tc->prev_cwnd;
1280 tc->ssthresh = tc->prev_ssthresh;
1281 tcp_cc_undo_recovery (tc);
1282 ASSERT (tc->rto_boff == 0);
1283 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
1287 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
1289 return (tcp_in_recovery (tc) && tc->rto_boff == 1
1291 && tcp_opts_tstamp (&tc->rcv_opts)
1292 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1296 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1298 return (tcp_cc_is_spurious_timeout_rxt (tc));
1302 tcp_should_fastrecover_sack (tcp_connection_t * tc)
1304 return (tc->sack_sb.lost_bytes
1305 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
1306 < tc->sack_sb.sacked_bytes));
1310 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
1314 /* If of of the two conditions lower hold, reset dupacks because
1315 * we're probably after timeout (RFC6582 heuristics).
1316 * If Cumulative ack does not cover more than congestion threshold,
1318 * 1) The following doesn't hold: The congestion window is greater
1319 * than SMSS bytes and the difference between highest_ack
1320 * and prev_highest_ack is at most 4*SMSS bytes
1321 * 2) Echoed timestamp in the last non-dup ack does not equal the
1324 if (seq_leq (tc->snd_una, tc->snd_congestion)
1325 && ((!(tc->cwnd > tc->snd_mss
1326 && tc->bytes_acked <= 4 * tc->snd_mss))
1327 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1329 tc->rcv_dupacks = 0;
1333 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1334 || tcp_should_fastrecover_sack (tc));
1338 tcp_cc_recover (tcp_connection_t * tc)
1340 sack_scoreboard_hole_t *hole;
1343 ASSERT (tcp_in_cong_recovery (tc));
1345 if (tcp_cc_is_spurious_retransmit (tc))
1347 tcp_cc_congestion_undo (tc);
1351 tc->rcv_dupacks = 0;
1352 tc->prr_delivered = 0;
1353 tc->rxt_delivered = 0;
1354 tc->snd_rxt_bytes = 0;
1357 tc->flags &= ~TCP_CONN_RXT_PENDING;
1359 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1361 /* Previous recovery left us congested. Continue sending as part
1362 * of the current recovery event with an updated snd_congestion */
1363 if (tc->sack_sb.sacked_bytes)
1365 tc->snd_congestion = tc->snd_nxt;
1366 tc->snd_rxt_ts = tcp_tstamp (tc);
1367 tc->prr_start = tc->snd_una;
1368 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1369 tcp_program_retransmit (tc);
1373 hole = scoreboard_first_hole (&tc->sack_sb);
1374 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
1375 scoreboard_clear (&tc->sack_sb);
1377 if (!tcp_in_recovery (tc) && !is_spurious)
1378 tcp_cc_recovered (tc);
1380 tcp_fastrecovery_off (tc);
1381 tcp_fastrecovery_first_off (tc);
1382 tcp_recovery_off (tc);
1383 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1385 ASSERT (tc->rto_boff == 0);
1386 ASSERT (!tcp_in_cong_recovery (tc));
1387 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
1392 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1394 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
1396 /* Congestion avoidance */
1397 tcp_cc_rcv_ack (tc, rs);
1399 /* If a cumulative ack, make sure dupacks is 0 */
1400 tc->rcv_dupacks = 0;
1402 /* When dupacks hits the threshold we only enter fast retransmit if
1403 * cumulative ack covers more than snd_congestion. Should snd_una
1404 * wrap this test may fail under otherwise valid circumstances.
1405 * Therefore, proactively update snd_congestion when wrap detected. */
1407 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1408 && seq_gt (tc->snd_congestion, tc->snd_una)))
1409 tc->snd_congestion = tc->snd_una - 1;
1413 * One function to rule them all ... and in the darkness bind them
1416 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
1419 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
1422 * If not in recovery, figure out if we should enter
1424 if (!tcp_in_cong_recovery (tc))
1429 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1430 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1432 if (tcp_should_fastrecover (tc, has_sack))
1434 tcp_cc_init_congestion (tc);
1437 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1439 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1440 tcp_program_retransmit (tc);
1447 * Already in recovery. See if we can exit and stop retransmitting
1450 if (seq_geq (tc->snd_una, tc->snd_congestion))
1452 /* If spurious return, we've already updated everything */
1453 if (tcp_cc_recover (tc))
1455 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1459 /* Treat as congestion avoidance ack */
1460 tcp_cc_rcv_ack (tc, rs);
1465 * Process (re)transmit feedback. Output path uses this to decide how much
1466 * more data to release into the network
1470 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
1471 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
1472 - tc->sack_sb.last_bytes_delivered;
1474 tcp_program_retransmit (tc);
1480 tc->rcv_dupacks += 1;
1481 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1483 tc->rxt_delivered = clib_max (tc->rxt_delivered + tc->bytes_acked,
1486 tc->prr_delivered += 1;
1488 tc->prr_delivered += tc->bytes_acked - tc->snd_mss * tc->rcv_dupacks;
1490 /* If partial ack, assume that the first un-acked segment was lost */
1491 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1492 tcp_fastrecovery_first_on (tc);
1494 tcp_program_retransmit (tc);
1498 * Notify cc of the event
1501 if (!tc->bytes_acked)
1503 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1507 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1508 * reset dupacks to 0. Also needed if in congestion recovery */
1509 tc->rcv_dupacks = 0;
1511 if (tcp_in_recovery (tc))
1512 tcp_cc_rcv_ack (tc, rs);
1514 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
1518 * Check if duplicate ack as per RFC5681 Sec. 2
1521 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
1524 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
1525 && seq_gt (tc->snd_nxt, tc->snd_una)
1526 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
1527 && (prev_snd_wnd == tc->snd_wnd));
1531 * Checks if ack is a congestion control event.
1534 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
1535 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
1537 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
1538 * defined to be 'duplicate' as well */
1539 *is_dack = tc->sack_sb.last_sacked_bytes
1540 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
1542 /* If reneging, wait for timer based retransmits */
1543 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
1546 return (*is_dack || tcp_in_cong_recovery (tc));
1550 * Process incoming ACK
1553 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1554 tcp_header_t * th, u32 * error)
1556 u32 prev_snd_wnd, prev_snd_una;
1557 tcp_rate_sample_t rs = { 0 };
1560 TCP_EVT (TCP_EVT_CC_STAT, tc);
1562 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1563 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1565 /* We've probably entered recovery and the peer still has some
1566 * of the data we've sent. Update snd_nxt and accept the ack */
1567 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1568 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1570 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1574 tc->errors.above_ack_wnd += 1;
1575 *error = TCP_ERROR_ACK_FUTURE;
1576 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1580 /* If old ACK, probably it's an old dupack */
1581 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1583 tc->errors.below_ack_wnd += 1;
1584 *error = TCP_ERROR_ACK_OLD;
1585 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1586 if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1587 tcp_cc_handle_event (tc, 0, 1);
1588 /* Don't drop yet */
1595 * Looks okay, process feedback
1598 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1599 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1601 prev_snd_wnd = tc->snd_wnd;
1602 prev_snd_una = tc->snd_una;
1603 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1604 vnet_buffer (b)->tcp.ack_number,
1605 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1606 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1607 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1608 tcp_validate_txf_size (tc, tc->bytes_acked);
1610 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1611 tcp_bt_sample_delivery_rate (tc, &rs);
1613 tcp_program_dequeue (wrk, tc);
1615 if (tc->bytes_acked)
1616 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1618 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1621 * Check if we have congestion event
1624 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1626 tcp_cc_handle_event (tc, &rs, is_dack);
1627 tc->dupacks_in += is_dack;
1628 if (!tcp_in_cong_recovery (tc))
1630 *error = TCP_ERROR_ACK_OK;
1633 *error = TCP_ERROR_ACK_DUP;
1634 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1640 * Update congestion control (slow start/congestion avoidance)
1642 tcp_cc_update (tc, &rs);
1643 *error = TCP_ERROR_ACK_OK;
1648 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1650 if (!tcp_disconnect_pending (tc))
1652 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1653 tcp_disconnect_pending_on (tc);
1658 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1660 u32 thread_index, *pending_disconnects;
1661 tcp_connection_t *tc;
1664 if (!vec_len (wrk->pending_disconnects))
1667 thread_index = wrk->vm->thread_index;
1668 pending_disconnects = wrk->pending_disconnects;
1669 for (i = 0; i < vec_len (pending_disconnects); i++)
1671 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1672 tcp_disconnect_pending_off (tc);
1673 session_transport_closing_notify (&tc->connection);
1675 _vec_len (wrk->pending_disconnects) = 0;
1679 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1682 /* Reject out-of-order fins */
1683 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1686 /* Account for the FIN and send ack */
1688 tc->flags |= TCP_CONN_FINRCVD;
1689 tcp_program_ack (tc);
1690 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1691 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1692 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1693 tcp_program_disconnect (wrk, tc);
1694 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1695 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1696 *error = TCP_ERROR_FIN_RCVD;
1699 #ifndef CLIB_MARCH_VARIANT
1701 tcp_sack_vector_is_sane (sack_block_t * sacks)
1704 for (i = 1; i < vec_len (sacks); i++)
1706 if (sacks[i - 1].end == sacks[i].start)
1713 * Build SACK list as per RFC2018.
1715 * Makes sure the first block contains the segment that generated the current
1716 * ACK and the following ones are the ones most recently reported in SACK
1719 * @param tc TCP connection for which the SACK list is updated
1720 * @param start Start sequence number of the newest SACK block
1721 * @param end End sequence of the newest SACK block
1724 tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1726 sack_block_t *new_list = tc->snd_sacks_fl, *block = 0;
1729 /* If the first segment is ooo add it to the list. Last write might've moved
1730 * rcv_nxt over the first segment. */
1731 if (seq_lt (tc->rcv_nxt, start))
1733 vec_add2 (new_list, block, 1);
1734 block->start = start;
1738 /* Find the blocks still worth keeping. */
1739 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1741 /* Discard if rcv_nxt advanced beyond current block */
1742 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
1745 /* Merge or drop if segment overlapped by the new segment */
1746 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1747 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1749 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1750 new_list[0].start = tc->snd_sacks[i].start;
1751 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1752 new_list[0].end = tc->snd_sacks[i].end;
1756 /* Save to new SACK list if we have space. */
1757 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1758 vec_add1 (new_list, tc->snd_sacks[i]);
1761 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
1763 /* Replace old vector with new one */
1764 vec_reset_length (tc->snd_sacks);
1765 tc->snd_sacks_fl = tc->snd_sacks;
1766 tc->snd_sacks = new_list;
1768 /* Segments should not 'touch' */
1769 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
1773 tcp_sack_list_bytes (tcp_connection_t * tc)
1776 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1777 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1780 #endif /* CLIB_MARCH_VARIANT */
1782 /** Enqueue data for delivery to application */
1784 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1787 int written, error = TCP_ERROR_ENQUEUED;
1789 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1791 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1792 1 /* queue event */ , 1);
1793 tc->bytes_in += written;
1795 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1797 /* Update rcv_nxt */
1798 if (PREDICT_TRUE (written == data_len))
1800 tc->rcv_nxt += written;
1802 /* If more data written than expected, account for out-of-order bytes. */
1803 else if (written > data_len)
1805 tc->rcv_nxt += written;
1806 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1808 else if (written > 0)
1810 /* We've written something but FIFO is probably full now */
1811 tc->rcv_nxt += written;
1812 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1816 return TCP_ERROR_FIFO_FULL;
1819 /* Update SACK list if need be */
1820 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1822 /* Remove SACK blocks that have been delivered */
1823 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1829 /** Enqueue out-of-order data */
1831 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1837 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1840 /* Enqueue out-of-order data with relative offset */
1841 rv = session_enqueue_stream_connection (&tc->connection, b,
1842 vnet_buffer (b)->tcp.seq_number -
1843 tc->rcv_nxt, 0 /* queue event */ ,
1846 /* Nothing written */
1849 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1850 return TCP_ERROR_FIFO_FULL;
1853 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1854 tc->bytes_in += data_len;
1856 /* Update SACK list if in use */
1857 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1859 ooo_segment_t *newest;
1862 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1864 /* Get the newest segment from the fifo */
1865 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1868 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1869 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1870 start = tc->rcv_nxt + offset;
1871 end = start + ooo_segment_length (s0->rx_fifo, newest);
1872 tcp_update_sack_list (tc, start, end);
1873 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1874 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1878 return TCP_ERROR_ENQUEUED_OOO;
1882 * Check if ACK could be delayed. If ack can be delayed, it should return
1883 * true for a full frame. If we're always acking return 0.
1886 tcp_can_delack (tcp_connection_t * tc)
1888 /* Send ack if ... */
1890 /* just sent a rcv wnd 0
1891 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1892 /* constrained to send ack */
1893 || (tc->flags & TCP_CONN_SNDACK) != 0
1894 /* we're almost out of tx wnd */
1895 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1902 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1904 u32 discard, first = b->current_length;
1905 vlib_main_t *vm = vlib_get_main ();
1907 /* Handle multi-buffer segments */
1908 if (n_bytes_to_drop > b->current_length)
1910 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1914 discard = clib_min (n_bytes_to_drop, b->current_length);
1915 vlib_buffer_advance (b, discard);
1916 b = vlib_get_buffer (vm, b->next_buffer);
1917 n_bytes_to_drop -= discard;
1919 while (n_bytes_to_drop);
1920 if (n_bytes_to_drop > first)
1921 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1924 vlib_buffer_advance (b, n_bytes_to_drop);
1925 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1930 * Receive buffer for connection and handle acks
1932 * It handles both in order or out-of-order data.
1935 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1938 u32 error, n_bytes_to_drop, n_data_bytes;
1940 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1941 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1942 ASSERT (n_data_bytes);
1943 tc->data_segs_in += 1;
1945 /* Handle out-of-order data */
1946 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1948 /* Old sequence numbers allowed through because they overlapped
1950 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1952 /* Completely in the past (possible retransmit). Ack
1953 * retransmissions since we may not have any data to send */
1954 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1956 tcp_program_ack (tc);
1957 error = TCP_ERROR_SEGMENT_OLD;
1961 /* Chop off the bytes in the past and see if what is left
1962 * can be enqueued in order */
1963 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1964 n_data_bytes -= n_bytes_to_drop;
1965 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1966 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1968 error = TCP_ERROR_SEGMENT_OLD;
1974 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1975 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1976 tcp_program_dupack (tc);
1977 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1978 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1979 tc->rcv_las + tc->rcv_wnd);
1985 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1986 * segments can be enqueued after fifo tail offset changes. */
1987 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1988 if (tcp_can_delack (tc))
1990 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1991 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
1995 tcp_program_ack (tc);
2003 tcp_header_t tcp_header;
2004 tcp_connection_t tcp_connection;
2008 format_tcp_rx_trace (u8 * s, va_list * args)
2010 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2011 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2012 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2013 u32 indent = format_get_indent (s);
2015 s = format (s, "%U\n%U%U",
2016 format_tcp_header, &t->tcp_header, 128,
2017 format_white_space, indent,
2018 format_tcp_connection, &t->tcp_connection, 1);
2024 format_tcp_rx_trace_short (u8 * s, va_list * args)
2026 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2027 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2028 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2030 s = format (s, "%d -> %d (%U)",
2031 clib_net_to_host_u16 (t->tcp_header.dst_port),
2032 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
2033 t->tcp_connection.state);
2039 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
2040 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
2044 clib_memcpy_fast (&t0->tcp_connection, tc0,
2045 sizeof (t0->tcp_connection));
2049 th0 = tcp_buffer_hdr (b0);
2051 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2055 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2056 vlib_frame_t * frame, u8 is_ip4)
2060 n_left = frame->n_vectors;
2061 from = vlib_frame_vector_args (frame);
2065 tcp_connection_t *tc0;
2072 b0 = vlib_get_buffer (vm, bi0);
2074 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2076 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2077 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2079 th0 = tcp_buffer_hdr (b0);
2080 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2089 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2090 u8 is_ip4, u32 evt, u32 val)
2093 vlib_node_increment_counter (vm, tcp4_node, evt, val);
2095 vlib_node_increment_counter (vm, tcp6_node, evt, val);
2098 #define tcp_maybe_inc_counter(node_id, err, count) \
2100 if (next0 != tcp_next_drop (is_ip4)) \
2101 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2102 tcp6_##node_id##_node.index, is_ip4, err, \
2105 #define tcp_inc_counter(node_id, err, count) \
2106 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2107 tcp6_##node_id##_node.index, is_ip4, \
2109 #define tcp_maybe_inc_err_counter(cnts, err) \
2111 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2113 #define tcp_inc_err_counter(cnts, err, val) \
2117 #define tcp_store_err_counters(node_id, cnts) \
2120 for (i = 0; i < TCP_N_ERROR; i++) \
2122 tcp_inc_counter(node_id, i, cnts[i]); \
2127 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2128 vlib_frame_t * frame, int is_ip4)
2130 u32 thread_index = vm->thread_index, errors = 0;
2131 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2132 u32 n_left_from, *from, *first_buffer;
2133 u16 err_counters[TCP_N_ERROR] = { 0 };
2135 if (node->flags & VLIB_NODE_FLAG_TRACE)
2136 tcp_established_trace_frame (vm, node, frame, is_ip4);
2138 first_buffer = from = vlib_frame_vector_args (frame);
2139 n_left_from = frame->n_vectors;
2141 while (n_left_from > 0)
2143 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2146 tcp_connection_t *tc0;
2148 if (n_left_from > 1)
2151 pb = vlib_get_buffer (vm, from[1]);
2152 vlib_prefetch_buffer_header (pb, LOAD);
2153 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2160 b0 = vlib_get_buffer (vm, bi0);
2161 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2164 if (PREDICT_FALSE (tc0 == 0))
2166 error0 = TCP_ERROR_INVALID_CONNECTION;
2170 th0 = tcp_buffer_hdr (b0);
2172 /* TODO header prediction fast path */
2174 /* 1-4: check SEQ, RST, SYN */
2175 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2177 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2181 /* 5: check the ACK field */
2182 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2185 /* 6: check the URG bit TODO */
2187 /* 7: process the segment text */
2188 if (vnet_buffer (b0)->tcp.data_len)
2189 error0 = tcp_segment_rcv (wrk, tc0, b0);
2191 /* 8: check the FIN bit */
2192 if (PREDICT_FALSE (tcp_is_fin (th0)))
2193 tcp_rcv_fin (wrk, tc0, b0, &error0);
2196 tcp_inc_err_counter (err_counters, error0, 1);
2199 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2201 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
2202 tcp_store_err_counters (established, err_counters);
2203 tcp_handle_postponed_dequeues (wrk);
2204 tcp_handle_disconnects (wrk);
2205 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
2207 return frame->n_vectors;
2210 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
2211 vlib_node_runtime_t * node,
2212 vlib_frame_t * from_frame)
2214 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2217 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
2218 vlib_node_runtime_t * node,
2219 vlib_frame_t * from_frame)
2221 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2225 VLIB_REGISTER_NODE (tcp4_established_node) =
2227 .name = "tcp4-established",
2228 /* Takes a vector of packets. */
2229 .vector_size = sizeof (u32),
2230 .n_errors = TCP_N_ERROR,
2231 .error_strings = tcp_error_strings,
2232 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2235 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2236 foreach_tcp_state_next
2239 .format_trace = format_tcp_rx_trace_short,
2244 VLIB_REGISTER_NODE (tcp6_established_node) =
2246 .name = "tcp6-established",
2247 /* Takes a vector of packets. */
2248 .vector_size = sizeof (u32),
2249 .n_errors = TCP_N_ERROR,
2250 .error_strings = tcp_error_strings,
2251 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2254 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2255 foreach_tcp_state_next
2258 .format_trace = format_tcp_rx_trace_short,
2264 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
2267 transport_connection_t *tmp = 0;
2274 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2279 if (tc->connection.is_ip4)
2281 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
2283 (!(ip4_address_compare
2284 (&ip4_hdr->src_address, &tc->connection.rmt_ip.ip4)
2285 && ip4_address_compare (&ip4_hdr->dst_address,
2286 &tc->connection.lcl_ip.ip4)));
2290 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
2292 (!(ip6_address_compare
2293 (&ip6_hdr->src_address, &tc->connection.rmt_ip.ip6)
2294 && ip6_address_compare (&ip6_hdr->dst_address,
2295 &tc->connection.lcl_ip.ip6)));
2298 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2299 && (tc->state == TCP_STATE_LISTEN
2300 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
2304 handle = session_lookup_half_open_handle (&tc->connection);
2305 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
2306 tc->c_proto, tc->c_is_ip4);
2310 if (tmp->lcl_port == hdr->dst_port
2311 && tmp->rmt_port == hdr->src_port)
2313 TCP_DBG ("half-open is valid!");
2322 * Lookup transport connection
2324 static tcp_connection_t *
2325 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2329 transport_connection_t *tconn;
2330 tcp_connection_t *tc;
2335 ip4 = vlib_buffer_get_current (b);
2336 tcp = ip4_next_header (ip4);
2337 tconn = session_lookup_connection_wt4 (fib_index,
2342 TRANSPORT_PROTO_TCP,
2343 thread_index, &is_filtered);
2344 tc = tcp_get_connection_from_transport (tconn);
2345 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2350 ip6 = vlib_buffer_get_current (b);
2351 tcp = ip6_next_header (ip6);
2352 tconn = session_lookup_connection_wt6 (fib_index,
2357 TRANSPORT_PROTO_TCP,
2358 thread_index, &is_filtered);
2359 tc = tcp_get_connection_from_transport (tconn);
2360 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2366 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
2368 vnet_main_t *vnm = vnet_get_main ();
2369 const dpo_id_t *dpo;
2370 const load_balance_t *lb;
2371 vnet_hw_interface_t *hw_if;
2372 u32 sw_if_idx, lb_idx;
2376 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
2377 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
2381 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
2382 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
2385 lb = load_balance_get (lb_idx);
2386 dpo = load_balance_get_bucket_i (lb, 0);
2388 sw_if_idx = dpo->dpoi_index;
2389 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
2391 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
2392 tc->cfg_flags |= TCP_CFG_F_TSO;
2396 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2397 vlib_frame_t * from_frame, int is_ip4)
2399 u32 n_left_from, *from, *first_buffer, errors = 0;
2400 u32 my_thread_index = vm->thread_index;
2401 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2403 from = first_buffer = vlib_frame_vector_args (from_frame);
2404 n_left_from = from_frame->n_vectors;
2406 while (n_left_from > 0)
2408 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2409 tcp_connection_t *tc0, *new_tc0;
2410 tcp_header_t *tcp0 = 0;
2418 b0 = vlib_get_buffer (vm, bi0);
2420 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2421 if (PREDICT_FALSE (tc0 == 0))
2423 error0 = TCP_ERROR_INVALID_CONNECTION;
2427 /* Half-open completed recently but the connection was't removed
2428 * yet by the owning thread */
2429 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2431 /* Make sure the connection actually exists */
2432 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2433 my_thread_index, is_ip4));
2434 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2438 ack0 = vnet_buffer (b0)->tcp.ack_number;
2439 seq0 = vnet_buffer (b0)->tcp.seq_number;
2440 tcp0 = tcp_buffer_hdr (b0);
2442 /* Crude check to see if the connection handle does not match
2443 * the packet. Probably connection just switched to established */
2444 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2445 || tcp0->src_port != tc0->c_rmt_port))
2447 error0 = TCP_ERROR_INVALID_CONNECTION;
2451 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2452 && !tcp_syn (tcp0)))
2454 error0 = TCP_ERROR_SEGMENT_INVALID;
2458 /* SYNs consume sequence numbers */
2459 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2462 * 1. check the ACK bit
2466 * If the ACK bit is set
2467 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2468 * the RST bit is set, if so drop the segment and return)
2469 * <SEQ=SEG.ACK><CTL=RST>
2470 * and discard the segment. Return.
2471 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2475 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2477 if (!tcp_rst (tcp0))
2478 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2479 error0 = TCP_ERROR_RCV_WND;
2483 /* Make sure ACK is valid */
2484 if (seq_gt (tc0->snd_una, ack0))
2486 error0 = TCP_ERROR_ACK_INVALID;
2492 * 2. check the RST bit
2497 /* If ACK is acceptable, signal client that peer is not
2498 * willing to accept connection and drop connection*/
2500 tcp_connection_reset (tc0);
2501 error0 = TCP_ERROR_RST_RCVD;
2506 * 3. check the security and precedence (skipped)
2510 * 4. check the SYN bit
2513 /* No SYN flag. Drop. */
2514 if (!tcp_syn (tcp0))
2516 error0 = TCP_ERROR_SEGMENT_INVALID;
2521 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2523 error0 = TCP_ERROR_OPTIONS;
2527 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2528 * current thread pool. */
2529 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2530 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2531 new_tc0->irs = seq0;
2532 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2533 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2535 /* If this is not the owning thread, wait for syn retransmit to
2536 * expire and cleanup then */
2537 if (tcp_half_open_connection_cleanup (tc0))
2538 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2540 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2542 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2543 new_tc0->tsval_recent_age = tcp_time_now ();
2546 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2547 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2549 new_tc0->rcv_wscale = 0;
2551 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2552 << new_tc0->snd_wscale;
2553 new_tc0->snd_wl1 = seq0;
2554 new_tc0->snd_wl2 = ack0;
2556 tcp_connection_init_vars (new_tc0);
2558 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2559 if (PREDICT_TRUE (tcp_ack (tcp0)))
2561 /* Our SYN is ACKed: we have iss < ack = snd_una */
2563 /* TODO Dequeue acknowledged segments if we support Fast Open */
2564 new_tc0->snd_una = ack0;
2565 new_tc0->state = TCP_STATE_ESTABLISHED;
2567 /* Make sure las is initialized for the wnd computation */
2568 new_tc0->rcv_las = new_tc0->rcv_nxt;
2570 /* Notify app that we have connection. If session layer can't
2571 * allocate session send reset */
2572 if (session_stream_connect_notify (&new_tc0->connection, 0))
2574 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2575 tcp_connection_cleanup (new_tc0);
2576 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2580 new_tc0->tx_fifo_size =
2581 transport_tx_fifo_size (&new_tc0->connection);
2582 /* Update rtt with the syn-ack sample */
2583 tcp_estimate_initial_rtt (new_tc0);
2584 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2585 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2587 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2590 new_tc0->state = TCP_STATE_SYN_RCVD;
2592 /* Notify app that we have connection */
2593 if (session_stream_connect_notify (&new_tc0->connection, 0))
2595 tcp_connection_cleanup (new_tc0);
2596 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2597 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2598 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2602 new_tc0->tx_fifo_size =
2603 transport_tx_fifo_size (&new_tc0->connection);
2604 new_tc0->rtt_ts = 0;
2605 tcp_init_snd_vars (new_tc0);
2606 tcp_send_synack (new_tc0);
2607 error0 = TCP_ERROR_SYNS_RCVD;
2611 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2612 tcp_check_tx_offload (new_tc0, is_ip4);
2614 /* Read data, if any */
2615 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2617 clib_warning ("rcvd data in syn-sent");
2618 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2619 if (error0 == TCP_ERROR_ACK_OK)
2620 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2624 /* Send ack now instead of programming it because connection was
2625 * just established and it's not optional. */
2626 tcp_send_ack (new_tc0);
2631 tcp_inc_counter (syn_sent, error0, 1);
2632 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2634 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2635 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2636 clib_memcpy_fast (&t0->tcp_connection, tc0,
2637 sizeof (t0->tcp_connection));
2641 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2643 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2644 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2646 return from_frame->n_vectors;
2649 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2650 vlib_node_runtime_t * node,
2651 vlib_frame_t * from_frame)
2653 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2656 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2657 vlib_node_runtime_t * node,
2658 vlib_frame_t * from_frame)
2660 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2664 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2666 .name = "tcp4-syn-sent",
2667 /* Takes a vector of packets. */
2668 .vector_size = sizeof (u32),
2669 .n_errors = TCP_N_ERROR,
2670 .error_strings = tcp_error_strings,
2671 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2674 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2675 foreach_tcp_state_next
2678 .format_trace = format_tcp_rx_trace_short,
2683 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2685 .name = "tcp6-syn-sent",
2686 /* Takes a vector of packets. */
2687 .vector_size = sizeof (u32),
2688 .n_errors = TCP_N_ERROR,
2689 .error_strings = tcp_error_strings,
2690 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2693 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2694 foreach_tcp_state_next
2697 .format_trace = format_tcp_rx_trace_short,
2702 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2703 * as per RFC793 p. 64
2706 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2707 vlib_frame_t * from_frame, int is_ip4)
2709 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2710 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2711 u32 n_left_from, *from, max_dequeue;
2713 from = first_buffer = vlib_frame_vector_args (from_frame);
2714 n_left_from = from_frame->n_vectors;
2716 while (n_left_from > 0)
2718 u32 bi0, error0 = TCP_ERROR_NONE;
2719 tcp_header_t *tcp0 = 0;
2720 tcp_connection_t *tc0;
2728 b0 = vlib_get_buffer (vm, bi0);
2729 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2731 if (PREDICT_FALSE (tc0 == 0))
2733 error0 = TCP_ERROR_INVALID_CONNECTION;
2737 tcp0 = tcp_buffer_hdr (b0);
2738 is_fin0 = tcp_is_fin (tcp0);
2742 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2744 tcp_connection_t *tmp;
2745 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2747 if (tmp->state != tc0->state)
2749 if (tc0->state != TCP_STATE_CLOSED)
2750 clib_warning ("state changed");
2757 * Special treatment for CLOSED
2759 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2761 error0 = TCP_ERROR_CONNECTION_CLOSED;
2766 * For all other states (except LISTEN)
2769 /* 1-4: check SEQ, RST, SYN */
2770 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2773 /* 5: check the ACK field */
2776 case TCP_STATE_SYN_RCVD:
2778 /* Make sure the segment is exactly right */
2779 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2781 tcp_connection_reset (tc0);
2782 error0 = TCP_ERROR_SEGMENT_INVALID;
2787 * If the segment acknowledgment is not acceptable, form a
2789 * <SEQ=SEG.ACK><CTL=RST>
2792 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2794 tcp_connection_reset (tc0);
2798 /* Update rtt and rto */
2799 tcp_estimate_initial_rtt (tc0);
2800 tcp_connection_tx_pacer_update (tc0);
2802 /* Switch state to ESTABLISHED */
2803 tc0->state = TCP_STATE_ESTABLISHED;
2804 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2806 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2807 tcp_check_tx_offload (tc0, is_ip4);
2809 /* Initialize session variables */
2810 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2811 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2812 << tc0->rcv_opts.wscale;
2813 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2814 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2816 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2817 tcp_retransmit_timer_reset (tc0);
2818 if (session_stream_accept_notify (&tc0->connection))
2820 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2821 tcp_connection_reset (tc0);
2824 error0 = TCP_ERROR_ACK_OK;
2826 case TCP_STATE_ESTABLISHED:
2827 /* We can get packets in established state here because they
2828 * were enqueued before state change */
2829 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2833 case TCP_STATE_FIN_WAIT_1:
2834 /* In addition to the processing for the ESTABLISHED state, if
2835 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2836 * continue processing in that state. */
2837 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2840 /* Still have to send the FIN */
2841 if (tc0->flags & TCP_CONN_FINPNDG)
2843 /* TX fifo finally drained */
2844 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2845 if (max_dequeue <= tc0->burst_acked)
2847 /* If a fin was received and data was acked extend wait */
2848 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2849 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2850 tcp_cfg.closewait_time);
2852 /* If FIN is ACKed */
2853 else if (tc0->snd_una == tc0->snd_nxt)
2855 /* Stop all retransmit timers because we have nothing more
2857 tcp_connection_timers_reset (tc0);
2859 /* We already have a FIN but didn't transition to CLOSING
2860 * because of outstanding tx data. Close the connection. */
2861 if (tc0->flags & TCP_CONN_FINRCVD)
2863 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2864 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE,
2865 tcp_cfg.cleanup_time);
2866 session_transport_closed_notify (&tc0->connection);
2870 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2871 /* Enable waitclose because we're willing to wait for peer's
2872 * FIN but not indefinitely. */
2873 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2875 /* Don't try to deq the FIN acked */
2876 if (tc0->burst_acked > 1)
2877 session_tx_fifo_dequeue_drop (&tc0->connection,
2878 tc0->burst_acked - 1);
2879 tc0->burst_acked = 0;
2882 case TCP_STATE_FIN_WAIT_2:
2883 /* In addition to the processing for the ESTABLISHED state, if
2884 * the retransmission queue is empty, the user's CLOSE can be
2885 * acknowledged ("ok") but do not delete the TCB. */
2886 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2888 tc0->burst_acked = 0;
2890 case TCP_STATE_CLOSE_WAIT:
2891 /* Do the same processing as for the ESTABLISHED state. */
2892 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2895 if (!(tc0->flags & TCP_CONN_FINPNDG))
2898 /* Still have outstanding tx data */
2899 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2900 if (max_dequeue > tc0->burst_acked)
2904 tcp_connection_timers_reset (tc0);
2905 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2906 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2908 case TCP_STATE_CLOSING:
2909 /* In addition to the processing for the ESTABLISHED state, if
2910 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2911 * otherwise ignore the segment. */
2912 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2915 if (tc0->snd_una != tc0->snd_nxt)
2918 tcp_connection_timers_reset (tc0);
2919 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2920 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2921 session_transport_closed_notify (&tc0->connection);
2925 case TCP_STATE_LAST_ACK:
2926 /* The only thing that [should] arrive in this state is an
2927 * acknowledgment of our FIN. If our FIN is now acknowledged,
2928 * delete the TCB, enter the CLOSED state, and return. */
2930 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2933 /* Apparently our ACK for the peer's FIN was lost */
2934 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2940 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2941 session_transport_closed_notify (&tc0->connection);
2943 /* Don't free the connection from the data path since
2944 * we can't ensure that we have no packets already enqueued
2945 * to output. Rely instead on the waitclose timer */
2946 tcp_connection_timers_reset (tc0);
2947 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
2952 case TCP_STATE_TIME_WAIT:
2953 /* The only thing that can arrive in this state is a
2954 * retransmission of the remote FIN. Acknowledge it, and restart
2955 * the 2 MSL timeout. */
2957 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2963 tcp_program_ack (tc0);
2964 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2972 /* 6: check the URG bit TODO */
2974 /* 7: process the segment text */
2977 case TCP_STATE_ESTABLISHED:
2978 case TCP_STATE_FIN_WAIT_1:
2979 case TCP_STATE_FIN_WAIT_2:
2980 if (vnet_buffer (b0)->tcp.data_len)
2981 error0 = tcp_segment_rcv (wrk, tc0, b0);
2983 case TCP_STATE_CLOSE_WAIT:
2984 case TCP_STATE_CLOSING:
2985 case TCP_STATE_LAST_ACK:
2986 case TCP_STATE_TIME_WAIT:
2987 /* This should not occur, since a FIN has been received from the
2988 * remote side. Ignore the segment text. */
2992 /* 8: check the FIN bit */
2996 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
3000 case TCP_STATE_ESTABLISHED:
3001 /* Account for the FIN and send ack */
3003 tcp_program_ack (tc0);
3004 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
3005 tcp_program_disconnect (wrk, tc0);
3006 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
3008 case TCP_STATE_SYN_RCVD:
3009 /* Send FIN-ACK, enter LAST-ACK and because the app was not
3010 * notified yet, set a cleanup timer instead of relying on
3011 * disconnect notify and the implicit close call. */
3012 tcp_connection_timers_reset (tc0);
3015 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3016 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3018 case TCP_STATE_CLOSE_WAIT:
3019 case TCP_STATE_CLOSING:
3020 case TCP_STATE_LAST_ACK:
3023 case TCP_STATE_FIN_WAIT_1:
3026 if (tc0->flags & TCP_CONN_FINPNDG)
3028 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
3029 * sending it. Since we already received a fin, do not wait
3031 tc0->flags |= TCP_CONN_FINRCVD;
3032 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3033 tcp_cfg.closewait_time);
3037 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
3038 tcp_program_ack (tc0);
3039 /* Wait for ACK for our FIN but not forever */
3040 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3041 tcp_cfg.closing_time);
3044 case TCP_STATE_FIN_WAIT_2:
3045 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
3047 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3048 tcp_connection_timers_reset (tc0);
3049 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3050 tcp_program_ack (tc0);
3051 session_transport_closed_notify (&tc0->connection);
3053 case TCP_STATE_TIME_WAIT:
3054 /* Remain in the TIME-WAIT state. Restart the time-wait
3057 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3060 error0 = TCP_ERROR_FIN_RCVD;
3064 tcp_inc_counter (rcv_process, error0, 1);
3065 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3067 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3068 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
3072 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
3074 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
3075 tcp_handle_postponed_dequeues (wrk);
3076 tcp_handle_disconnects (wrk);
3077 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3079 return from_frame->n_vectors;
3082 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
3083 vlib_node_runtime_t * node,
3084 vlib_frame_t * from_frame)
3086 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3089 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
3090 vlib_node_runtime_t * node,
3091 vlib_frame_t * from_frame)
3093 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3097 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
3099 .name = "tcp4-rcv-process",
3100 /* Takes a vector of packets. */
3101 .vector_size = sizeof (u32),
3102 .n_errors = TCP_N_ERROR,
3103 .error_strings = tcp_error_strings,
3104 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3107 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3108 foreach_tcp_state_next
3111 .format_trace = format_tcp_rx_trace_short,
3116 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3118 .name = "tcp6-rcv-process",
3119 /* Takes a vector of packets. */
3120 .vector_size = sizeof (u32),
3121 .n_errors = TCP_N_ERROR,
3122 .error_strings = tcp_error_strings,
3123 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3126 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3127 foreach_tcp_state_next
3130 .format_trace = format_tcp_rx_trace_short,
3135 * LISTEN state processing as per RFC 793 p. 65
3138 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3139 vlib_frame_t * from_frame, int is_ip4)
3141 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3142 u32 my_thread_index = vm->thread_index;
3144 from = first_buffer = vlib_frame_vector_args (from_frame);
3145 n_left_from = from_frame->n_vectors;
3147 while (n_left_from > 0)
3152 tcp_header_t *th0 = 0;
3153 tcp_connection_t *lc0;
3156 tcp_connection_t *child0;
3157 u32 error0 = TCP_ERROR_NONE;
3163 b0 = vlib_get_buffer (vm, bi0);
3164 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3168 ip40 = vlib_buffer_get_current (b0);
3169 th0 = ip4_next_header (ip40);
3173 ip60 = vlib_buffer_get_current (b0);
3174 th0 = ip6_next_header (ip60);
3177 /* Create child session. For syn-flood protection use filter */
3179 /* 1. first check for an RST: handled in dispatch */
3180 /* if (tcp_rst (th0))
3184 /* 2. second check for an ACK: handled in dispatch */
3185 /* if (tcp_ack (th0))
3187 tcp_send_reset (b0, is_ip4);
3192 /* 3. check for a SYN (did that already) */
3194 /* Make sure connection wasn't just created */
3195 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3197 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3199 error0 = TCP_ERROR_CREATE_EXISTS;
3203 /* Create child session and send SYN-ACK */
3204 child0 = tcp_connection_alloc (my_thread_index);
3205 child0->c_lcl_port = th0->dst_port;
3206 child0->c_rmt_port = th0->src_port;
3207 child0->c_is_ip4 = is_ip4;
3208 child0->state = TCP_STATE_SYN_RCVD;
3209 child0->c_fib_index = lc0->c_fib_index;
3210 child0->cc_algo = lc0->cc_algo;
3214 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3215 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3219 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3220 sizeof (ip6_address_t));
3221 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3222 sizeof (ip6_address_t));
3225 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3227 error0 = TCP_ERROR_OPTIONS;
3228 tcp_connection_free (child0);
3232 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3233 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3234 child0->rcv_las = child0->rcv_nxt;
3235 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3237 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3238 * segments are used to initialize PAWS. */
3239 if (tcp_opts_tstamp (&child0->rcv_opts))
3241 child0->tsval_recent = child0->rcv_opts.tsval;
3242 child0->tsval_recent_age = tcp_time_now ();
3245 if (tcp_opts_wscale (&child0->rcv_opts))
3246 child0->snd_wscale = child0->rcv_opts.wscale;
3248 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3249 << child0->snd_wscale;
3250 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3251 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3253 tcp_connection_init_vars (child0);
3254 child0->rto = TCP_RTO_MIN;
3256 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3257 lc0->c_thread_index, 0 /* notify */ ))
3259 tcp_connection_cleanup (child0);
3260 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3264 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3265 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3266 tcp_send_synack (child0);
3270 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3272 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3273 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3274 clib_memcpy_fast (&t0->tcp_connection, lc0,
3275 sizeof (t0->tcp_connection));
3278 n_syns += (error0 == TCP_ERROR_NONE);
3281 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3282 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3284 return from_frame->n_vectors;
3287 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3288 vlib_frame_t * from_frame)
3290 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3293 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3294 vlib_frame_t * from_frame)
3296 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3300 VLIB_REGISTER_NODE (tcp4_listen_node) =
3302 .name = "tcp4-listen",
3303 /* Takes a vector of packets. */
3304 .vector_size = sizeof (u32),
3305 .n_errors = TCP_N_ERROR,
3306 .error_strings = tcp_error_strings,
3307 .n_next_nodes = TCP_LISTEN_N_NEXT,
3310 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3311 foreach_tcp_state_next
3314 .format_trace = format_tcp_rx_trace_short,
3319 VLIB_REGISTER_NODE (tcp6_listen_node) =
3321 .name = "tcp6-listen",
3322 /* Takes a vector of packets. */
3323 .vector_size = sizeof (u32),
3324 .n_errors = TCP_N_ERROR,
3325 .error_strings = tcp_error_strings,
3326 .n_next_nodes = TCP_LISTEN_N_NEXT,
3329 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3330 foreach_tcp_state_next
3333 .format_trace = format_tcp_rx_trace_short,
3337 typedef enum _tcp_input_next
3339 TCP_INPUT_NEXT_DROP,
3340 TCP_INPUT_NEXT_LISTEN,
3341 TCP_INPUT_NEXT_RCV_PROCESS,
3342 TCP_INPUT_NEXT_SYN_SENT,
3343 TCP_INPUT_NEXT_ESTABLISHED,
3344 TCP_INPUT_NEXT_RESET,
3345 TCP_INPUT_NEXT_PUNT,
3349 #define foreach_tcp4_input_next \
3350 _ (DROP, "ip4-drop") \
3351 _ (LISTEN, "tcp4-listen") \
3352 _ (RCV_PROCESS, "tcp4-rcv-process") \
3353 _ (SYN_SENT, "tcp4-syn-sent") \
3354 _ (ESTABLISHED, "tcp4-established") \
3355 _ (RESET, "tcp4-reset") \
3356 _ (PUNT, "ip4-punt")
3358 #define foreach_tcp6_input_next \
3359 _ (DROP, "ip6-drop") \
3360 _ (LISTEN, "tcp6-listen") \
3361 _ (RCV_PROCESS, "tcp6-rcv-process") \
3362 _ (SYN_SENT, "tcp6-syn-sent") \
3363 _ (ESTABLISHED, "tcp6-established") \
3364 _ (RESET, "tcp6-reset") \
3365 _ (PUNT, "ip6-punt")
3367 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3370 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3371 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3373 tcp_connection_t *tc;
3378 for (i = 0; i < n_bufs; i++)
3380 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3382 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3383 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3385 tcp = vlib_buffer_get_current (bs[i]);
3386 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3392 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3394 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3396 *next = TCP_INPUT_NEXT_DROP;
3398 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3400 *next = TCP_INPUT_NEXT_PUNT;
3401 *error = TCP_ERROR_PUNT;
3405 *next = TCP_INPUT_NEXT_RESET;
3406 *error = TCP_ERROR_NO_LISTENER;
3410 always_inline tcp_connection_t *
3411 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3412 u8 is_ip4, u8 is_nolookup)
3414 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3415 int n_advance_bytes, n_data_bytes;
3416 transport_connection_t *tc;
3422 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3423 int ip_hdr_bytes = ip4_header_bytes (ip4);
3424 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3426 *error = TCP_ERROR_LENGTH;
3429 tcp = ip4_next_header (ip4);
3430 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3431 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3432 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3434 /* Length check. Checksum computed by ipx_local no need to compute again */
3435 if (PREDICT_FALSE (n_data_bytes < 0))
3437 *error = TCP_ERROR_LENGTH;
3442 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3443 &ip4->src_address, tcp->dst_port,
3445 TRANSPORT_PROTO_TCP, thread_index,
3450 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3451 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3453 *error = TCP_ERROR_LENGTH;
3456 tcp = ip6_next_header (ip6);
3457 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3458 n_advance_bytes = tcp_header_bytes (tcp);
3459 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3461 n_advance_bytes += sizeof (ip6[0]);
3463 if (PREDICT_FALSE (n_data_bytes < 0))
3465 *error = TCP_ERROR_LENGTH;
3472 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3474 ip4_main_t *im = &ip4_main;
3475 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3476 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3479 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3481 tcp->dst_port, tcp->src_port,
3482 TRANSPORT_PROTO_TCP,
3483 thread_index, &result);
3489 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3490 tcp.connection_index,
3493 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3494 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3495 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3496 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3497 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3499 vnet_buffer (b)->tcp.flags = 0;
3501 *error = result ? TCP_ERROR_NONE + result : *error;
3503 return tcp_get_connection_from_transport (tc);
3507 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3508 vlib_buffer_t * b, u16 * next, u32 * error)
3513 tcp = tcp_buffer_hdr (b);
3514 flags = tcp->flags & filter_flags;
3515 *next = tm->dispatch_table[tc->state][flags].next;
3516 *error = tm->dispatch_table[tc->state][flags].error;
3519 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3520 || *next == TCP_INPUT_NEXT_RESET))
3522 /* Overload tcp flags to store state */
3523 tcp_state_t state = tc->state;
3524 vnet_buffer (b)->tcp.flags = tc->state;
3526 if (*error == TCP_ERROR_DISPATCH)
3527 clib_warning ("tcp conn %u disp error state %U flags %U",
3528 tc->c_c_index, format_tcp_state, state,
3529 format_tcp_flags, (int) flags);
3534 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3535 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3537 u32 n_left_from, *from, thread_index = vm->thread_index;
3538 tcp_main_t *tm = vnet_get_tcp_main ();
3539 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3540 u16 nexts[VLIB_FRAME_SIZE], *next;
3542 tcp_set_time_now (tcp_get_worker (thread_index));
3544 from = vlib_frame_vector_args (frame);
3545 n_left_from = frame->n_vectors;
3546 vlib_get_buffers (vm, from, bufs, n_left_from);
3551 while (n_left_from >= 4)
3553 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3554 tcp_connection_t *tc0, *tc1;
3557 vlib_prefetch_buffer_header (b[2], STORE);
3558 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3560 vlib_prefetch_buffer_header (b[3], STORE);
3561 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3564 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3566 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3568 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3571 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3573 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3574 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3576 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3577 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3579 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3580 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3584 if (PREDICT_TRUE (tc0 != 0))
3586 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3587 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3588 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3591 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3593 if (PREDICT_TRUE (tc1 != 0))
3595 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3596 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3597 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3600 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3607 while (n_left_from > 0)
3609 tcp_connection_t *tc0;
3610 u32 error0 = TCP_ERROR_NO_LISTENER;
3612 if (n_left_from > 1)
3614 vlib_prefetch_buffer_header (b[1], STORE);
3615 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3618 next[0] = TCP_INPUT_NEXT_DROP;
3619 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3621 if (PREDICT_TRUE (tc0 != 0))
3623 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3624 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3625 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3628 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3635 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3636 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3638 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3639 return frame->n_vectors;
3642 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3643 vlib_node_runtime_t * node,
3644 vlib_frame_t * from_frame)
3646 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3647 1 /* is_nolookup */ );
3650 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3651 vlib_node_runtime_t * node,
3652 vlib_frame_t * from_frame)
3654 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3655 1 /* is_nolookup */ );
3659 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3661 .name = "tcp4-input-nolookup",
3662 /* Takes a vector of packets. */
3663 .vector_size = sizeof (u32),
3664 .n_errors = TCP_N_ERROR,
3665 .error_strings = tcp_error_strings,
3666 .n_next_nodes = TCP_INPUT_N_NEXT,
3669 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3670 foreach_tcp4_input_next
3673 .format_buffer = format_tcp_header,
3674 .format_trace = format_tcp_rx_trace,
3679 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3681 .name = "tcp6-input-nolookup",
3682 /* Takes a vector of packets. */
3683 .vector_size = sizeof (u32),
3684 .n_errors = TCP_N_ERROR,
3685 .error_strings = tcp_error_strings,
3686 .n_next_nodes = TCP_INPUT_N_NEXT,
3689 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3690 foreach_tcp6_input_next
3693 .format_buffer = format_tcp_header,
3694 .format_trace = format_tcp_rx_trace,
3698 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3699 vlib_frame_t * from_frame)
3701 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3702 0 /* is_nolookup */ );
3705 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3706 vlib_frame_t * from_frame)
3708 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3709 0 /* is_nolookup */ );
3713 VLIB_REGISTER_NODE (tcp4_input_node) =
3715 .name = "tcp4-input",
3716 /* Takes a vector of packets. */
3717 .vector_size = sizeof (u32),
3718 .n_errors = TCP_N_ERROR,
3719 .error_strings = tcp_error_strings,
3720 .n_next_nodes = TCP_INPUT_N_NEXT,
3723 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3724 foreach_tcp4_input_next
3727 .format_buffer = format_tcp_header,
3728 .format_trace = format_tcp_rx_trace,
3733 VLIB_REGISTER_NODE (tcp6_input_node) =
3735 .name = "tcp6-input",
3736 /* Takes a vector of packets. */
3737 .vector_size = sizeof (u32),
3738 .n_errors = TCP_N_ERROR,
3739 .error_strings = tcp_error_strings,
3740 .n_next_nodes = TCP_INPUT_N_NEXT,
3743 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3744 foreach_tcp6_input_next
3747 .format_buffer = format_tcp_header,
3748 .format_trace = format_tcp_rx_trace,
3752 #ifndef CLIB_MARCH_VARIANT
3754 tcp_dispatch_table_init (tcp_main_t * tm)
3757 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3758 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3760 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3761 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3764 #define _(t,f,n,e) \
3766 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3767 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3770 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3771 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3772 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3773 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3774 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3775 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3776 TCP_ERROR_ACK_INVALID);
3777 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3778 TCP_ERROR_SEGMENT_INVALID);
3779 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3780 TCP_ERROR_SEGMENT_INVALID);
3781 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3782 TCP_ERROR_INVALID_CONNECTION);
3783 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3784 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3785 TCP_ERROR_SEGMENT_INVALID);
3786 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3787 TCP_ERROR_SEGMENT_INVALID);
3788 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3790 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3791 TCP_ERROR_SEGMENT_INVALID);
3792 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3793 TCP_ERROR_SEGMENT_INVALID);
3794 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3795 TCP_ERROR_SEGMENT_INVALID);
3796 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3797 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3798 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3799 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3800 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3801 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3803 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3804 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3806 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3808 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3809 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3810 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3811 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3813 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3815 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3816 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3817 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3819 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3820 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3821 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3822 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3823 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3824 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3825 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3826 /* SYN-ACK for a SYN */
3827 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3829 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3830 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3831 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3833 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3834 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3836 /* ACK for for established connection -> tcp-established. */
3837 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3838 /* FIN for for established connection -> tcp-established. */
3839 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3840 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3842 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3844 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3845 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3846 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3848 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3849 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3850 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3851 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3852 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3853 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3854 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3855 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3857 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3858 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3860 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3862 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3863 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3864 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3865 /* ACK or FIN-ACK to our FIN */
3866 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3867 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3869 /* FIN in reply to our FIN from the other side */
3870 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3871 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3872 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3874 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3875 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3876 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3877 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3878 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3879 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3880 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3882 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3883 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3884 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3885 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3887 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3889 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3890 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3891 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3892 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3894 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3895 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3896 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3897 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3899 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3901 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3902 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3903 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3904 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3906 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3907 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3909 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3911 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3912 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3913 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3915 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3916 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3917 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3918 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3919 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3920 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3921 /* FIN confirming that the peer (app) has closed */
3922 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3923 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3924 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3926 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3927 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3929 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3930 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3932 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3933 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3935 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3936 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3937 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3938 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3940 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3942 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3943 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3944 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3946 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3947 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3948 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3949 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3950 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3951 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3952 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3953 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3955 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3956 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3958 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3960 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3961 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3962 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3963 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3964 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3966 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3967 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3969 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3970 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3971 * incoming segment not containing a RST causes a RST to be sent in
3973 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3974 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3975 TCP_ERROR_CONNECTION_CLOSED);
3976 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3977 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3978 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3983 static clib_error_t *
3984 tcp_input_init (vlib_main_t * vm)
3986 clib_error_t *error = 0;
3987 tcp_main_t *tm = vnet_get_tcp_main ();
3989 if ((error = vlib_call_init_function (vm, tcp_init)))
3992 /* Initialize dispatch table. */
3993 tcp_dispatch_table_init (tm);
3998 VLIB_INIT_FUNCTION (tcp_input_init);
4000 #endif /* CLIB_MARCH_VARIANT */
4003 * fd.io coding-style-patch-verification: ON
4006 * eval: (c-set-style "gnu")