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.h>
20 #include <vnet/tcp/tcp_inlines.h>
21 #include <vnet/session/session.h>
24 static vlib_error_desc_t tcp_input_error_counters[] = {
25 #define tcp_error(f, n, s, d) { #n, d, VL_COUNTER_SEVERITY_##s },
26 #include <vnet/tcp/tcp_error.def>
30 typedef enum _tcp_input_next
33 TCP_INPUT_NEXT_LISTEN,
34 TCP_INPUT_NEXT_RCV_PROCESS,
35 TCP_INPUT_NEXT_SYN_SENT,
36 TCP_INPUT_NEXT_ESTABLISHED,
43 * Validate segment sequence number. As per RFC793:
45 * Segment Receive Test
47 * ------- ------- -------------------------------------------
48 * 0 0 SEG.SEQ = RCV.NXT
49 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
51 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
52 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
54 * This ultimately consists in checking if segment falls within the window.
55 * The one important difference compared to RFC793 is that we use rcv_las,
56 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
57 * peer's reference when computing our receive window.
60 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
61 * however, is too strict when we have retransmits. Instead we just check that
62 * the seq is not beyond the right edge and that the end of the segment is not
63 * less than the left edge.
65 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
66 * use rcv_nxt in the right edge window test instead of rcv_las.
70 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
72 return (seq_geq (end_seq, tc->rcv_las)
73 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
77 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
78 * timestamp to echo and it's less than tsval_recent, drop segment
79 * but still send an ACK in order to retain TCP's mechanism for detecting
80 * and recovering from half-open connections
82 * Or at least that's what the theory says. It seems that this might not work
83 * very well with packet reordering and fast retransmit. XXX
86 tcp_segment_check_paws (tcp_connection_t * tc)
88 return tcp_opts_tstamp (&tc->rcv_opts)
89 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
96 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
99 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
100 * of an incoming segment:
101 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
102 * then the TSval from the segment is copied to TS.Recent;
103 * otherwise, the TSval is ignored.
105 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
106 && seq_leq (tc->rcv_las, seq_end))
108 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
109 tc->tsval_recent = tc->rcv_opts.tsval;
110 tc->tsval_recent_age = tcp_time_tstamp (tc->c_thread_index);
115 tcp_handle_rst (tcp_connection_t * tc)
117 switch (tc->rst_state)
119 case TCP_STATE_SYN_RCVD:
120 /* Cleanup everything. App wasn't notified yet */
121 session_transport_delete_notify (&tc->connection);
122 tcp_connection_cleanup (tc);
124 case TCP_STATE_SYN_SENT:
125 session_stream_connect_notify (&tc->connection, SESSION_E_REFUSED);
126 tcp_connection_cleanup (tc);
128 case TCP_STATE_ESTABLISHED:
129 session_transport_reset_notify (&tc->connection);
130 session_transport_closed_notify (&tc->connection);
132 case TCP_STATE_CLOSE_WAIT:
133 case TCP_STATE_FIN_WAIT_1:
134 case TCP_STATE_FIN_WAIT_2:
135 case TCP_STATE_CLOSING:
136 case TCP_STATE_LAST_ACK:
137 session_transport_closed_notify (&tc->connection);
139 case TCP_STATE_CLOSED:
140 case TCP_STATE_TIME_WAIT:
143 TCP_DBG ("reset state: %u", tc->state);
148 tcp_program_reset_ntf (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
150 if (!tcp_disconnect_pending (tc))
152 tc->rst_state = tc->state;
153 vec_add1 (wrk->pending_resets, tc->c_c_index);
154 tcp_disconnect_pending_on (tc);
159 * Handle reset packet
161 * Programs disconnect/reset notification that should be sent
162 * later by calling @ref tcp_handle_disconnects
165 tcp_rcv_rst (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
167 TCP_EVT (TCP_EVT_RST_RCVD, tc);
170 case TCP_STATE_SYN_RCVD:
171 tcp_program_reset_ntf (wrk, tc);
172 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
174 case TCP_STATE_SYN_SENT:
175 /* Do not program ntf because the connection is half-open */
176 tc->rst_state = tc->state;
179 case TCP_STATE_ESTABLISHED:
180 tcp_connection_timers_reset (tc);
181 tcp_cong_recovery_off (tc);
182 tcp_program_reset_ntf (wrk, tc);
183 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
184 tcp_program_cleanup (wrk, tc);
186 case TCP_STATE_CLOSE_WAIT:
187 case TCP_STATE_FIN_WAIT_1:
188 case TCP_STATE_FIN_WAIT_2:
189 case TCP_STATE_CLOSING:
190 case TCP_STATE_LAST_ACK:
191 tcp_connection_timers_reset (tc);
192 tcp_cong_recovery_off (tc);
193 tcp_program_reset_ntf (wrk, tc);
194 /* Make sure we mark the session as closed. In some states we may
195 * be still trying to send data */
196 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
197 tcp_program_cleanup (wrk, tc);
199 case TCP_STATE_CLOSED:
200 case TCP_STATE_TIME_WAIT:
203 TCP_DBG ("reset state: %u", tc->state);
208 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
210 * It first verifies if segment has a wrapped sequence number (PAWS) and then
211 * does the processing associated to the first four steps (ignoring security
212 * and precedence): sequence number, rst bit and syn bit checks.
214 * @return 0 if segments passes validation.
217 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
218 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
220 /* We could get a burst of RSTs interleaved with acks */
221 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
223 tcp_send_reset (tc0);
224 *error0 = TCP_ERROR_CONNECTION_CLOSED;
228 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
230 *error0 = TCP_ERROR_SEGMENT_INVALID;
234 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
236 *error0 = TCP_ERROR_OPTIONS;
240 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
242 *error0 = TCP_ERROR_PAWS;
243 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
244 vnet_buffer (b0)->tcp.seq_end);
246 /* If it just so happens that a segment updates tsval_recent for a
247 * segment over 24 days old, invalidate tsval_recent. */
248 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
249 tcp_time_tstamp (tc0->c_thread_index)))
251 tc0->tsval_recent = tc0->rcv_opts.tsval;
252 clib_warning ("paws failed: 24-day old segment");
254 /* Drop after ack if not rst. Resets can fail paws check as per
255 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
256 * be subjected to the PAWS check by verifying an acceptable value in
258 else if (!tcp_rst (th0))
260 tcp_program_ack (tc0);
261 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
266 /* 1st: check sequence number */
267 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
268 vnet_buffer (b0)->tcp.seq_end))
270 /* SYN/SYN-ACK retransmit */
272 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
274 tcp_options_parse (th0, &tc0->rcv_opts, 1);
275 if (tc0->state == TCP_STATE_SYN_RCVD)
277 tcp_send_synack (tc0);
278 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
279 *error0 = TCP_ERROR_SYNS_RCVD;
283 tcp_program_ack (tc0);
284 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
285 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
290 /* If our window is 0 and the packet is in sequence, let it pass
291 * through for ack processing. It should be dropped later. */
292 if (tc0->rcv_wnd < tc0->snd_mss
293 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
296 /* If we entered recovery and peer did so as well, there's a chance that
297 * dup acks won't be acceptable on either end because seq_end may be less
298 * than rcv_las. This can happen if acks are lost in both directions. */
299 if (tcp_in_recovery (tc0)
300 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
301 tc0->rcv_las - tc0->rcv_wnd)
302 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
303 tc0->rcv_nxt + tc0->rcv_wnd))
306 *error0 = TCP_ERROR_RCV_WND;
308 /* If we advertised a zero rcv_wnd and the segment is in the past or the
309 * next one that we expect, it is probably a window probe */
310 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
311 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
312 tc0->rcv_las + tc0->rcv_opts.mss))
313 *error0 = TCP_ERROR_ZERO_RWND;
315 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
318 /* If not RST, send dup ack */
321 tcp_program_dupack (tc0);
322 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
330 /* 2nd: check the RST bit */
331 if (PREDICT_FALSE (tcp_rst (th0)))
333 tcp_rcv_rst (wrk, tc0);
334 *error0 = TCP_ERROR_RST_RCVD;
338 /* 3rd: check security and precedence (skip) */
340 /* 4th: check the SYN bit (in window) */
341 if (PREDICT_FALSE (tcp_syn (th0)))
343 /* As per RFC5961 send challenge ack instead of reset */
344 tcp_program_ack (tc0);
345 *error0 = TCP_ERROR_SPURIOUS_SYN;
349 /* If segment in window, save timestamp */
350 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
351 vnet_buffer (b0)->tcp.seq_end);
359 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
361 /* SND.UNA =< SEG.ACK =< SND.NXT */
362 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
363 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
365 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
366 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
368 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
371 *error = TCP_ERROR_ACK_INVALID;
376 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
377 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
378 *error = TCP_ERROR_ACK_OK;
383 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
385 * Note that although in the original article srtt and rttvar are scaled
386 * to minimize round-off errors, here we don't. Instead, we rely on
387 * better precision time measurements.
389 * A known limitation of the algorithm is that a drop in rtt results in a
390 * rttvar increase and bigger RTO.
392 * mrtt must be provided in @ref TCP_TICK multiples, i.e., in us. Note that
393 * timestamps are measured as ms ticks so they must be converted before
394 * calling this function.
397 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
401 err = mrtt - tc->srtt;
402 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
403 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
404 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
408 tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
410 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
414 * Update rtt estimate
416 * We have potentially three sources of rtt measurements:
418 * TSOPT difference between current and echoed timestamp. It has ms
419 * precision and can be computed per ack
420 * ACK timing one sequence number is tracked per rtt with us (micro second)
422 * rate sample if enabled, all outstanding bytes are tracked with us
423 * precision. Every ack and sack are a rtt sample
425 * Middle boxes are known to fiddle with TCP options so we give higher
426 * priority to ACK timing.
428 * For now, rate sample rtts are only used under congestion.
431 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
435 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
436 * RTT because they're ambiguous. */
437 if (tcp_in_cong_recovery (tc))
439 /* Accept rtt estimates for samples that have not been retransmitted */
440 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
441 || (rs->flags & TCP_BTS_IS_RXT))
444 tcp_estimate_rtt_us (tc, rs->rtt_time);
445 mrtt = rs->rtt_time * THZ;
449 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
451 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
452 tcp_estimate_rtt_us (tc, sample);
453 mrtt = clib_max ((u32) (sample * THZ), 1);
454 /* Allow measuring of a new RTT */
457 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
458 * snd_una, i.e., the left side of the send window:
459 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
460 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
462 mrtt = clib_max (tcp_tstamp (tc) - tc->rcv_opts.tsecr, 1);
463 mrtt *= TCP_TSTP_TO_HZ;
468 /* Ignore dubious measurements */
469 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
472 tcp_estimate_rtt (tc, mrtt);
476 /* If we got here something must've been ACKed so make sure boff is 0,
477 * even if mrtt is not valid since we update the rto lower */
485 tcp_estimate_initial_rtt (tcp_connection_t * tc)
487 u8 thread_index = vlib_num_workers ()? 1 : 0;
492 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
493 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
494 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
499 mrtt = tcp_tstamp (tc) - tc->rcv_opts.tsecr;
500 mrtt = clib_max (mrtt, 1) * TCP_TSTP_TO_HZ;
501 /* Due to retransmits we don't know the initial mrtt */
502 if (tc->rto_boff && mrtt > 1 * THZ)
504 tc->mrtt_us = (f64) mrtt *TCP_TICK;
507 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
509 /* First measurement as per RFC 6298 */
511 tc->rttvar = mrtt >> 1;
517 * Dequeue bytes for connections that have received acks in last burst
520 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
522 u32 thread_index = wrk->vm->thread_index;
523 u32 *pending_deq_acked;
524 tcp_connection_t *tc;
527 if (!vec_len (wrk->pending_deq_acked))
530 pending_deq_acked = wrk->pending_deq_acked;
531 for (i = 0; i < vec_len (pending_deq_acked); i++)
533 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
534 tc->flags &= ~TCP_CONN_DEQ_PENDING;
536 if (PREDICT_FALSE (!tc->burst_acked))
539 /* Dequeue the newly ACKed bytes */
540 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
541 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
543 if (tcp_is_descheduled (tc))
546 /* If everything has been acked, stop retransmit timer
547 * otherwise update. */
548 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
550 /* Update pacer based on our new cwnd estimate */
551 tcp_connection_tx_pacer_update (tc);
555 vec_set_len (wrk->pending_deq_acked, 0);
559 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
561 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
563 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
564 tc->flags |= TCP_CONN_DEQ_PENDING;
566 tc->burst_acked += tc->bytes_acked;
570 * Try to update snd_wnd based on feedback received from peer.
572 * If successful, and new window is 'effectively' 0, activate persist
576 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
578 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
579 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
580 if (seq_lt (tc->snd_wl1, seq)
581 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
583 tc->snd_wnd = snd_wnd;
586 TCP_EVT (TCP_EVT_SND_WND, tc);
588 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
590 if (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
592 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
594 /* Set persist timer if we just got 0 wnd. If already set,
595 * update it because some data sent with snd_wnd < snd_mss was
597 if (tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
598 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
599 tcp_persist_timer_set (&wrk->timer_wheel, tc);
604 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
606 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
607 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
610 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
613 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
623 * Init loss recovery/fast recovery.
625 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
626 * updated in @ref tcp_cc_handle_event after fast retransmit
629 tcp_cc_init_congestion (tcp_connection_t * tc)
631 tcp_fastrecovery_on (tc);
632 tc->snd_congestion = tc->snd_nxt;
633 tc->cwnd_acc_bytes = 0;
634 tc->snd_rxt_bytes = 0;
635 tc->rxt_delivered = 0;
636 tc->prr_delivered = 0;
637 tc->prr_start = tc->snd_una;
638 tc->prev_ssthresh = tc->ssthresh;
639 tc->prev_cwnd = tc->cwnd;
641 tc->snd_rxt_ts = tcp_tstamp (tc);
642 tcp_cc_congestion (tc);
644 /* Post retransmit update cwnd to ssthresh and account for the
645 * three segments that have left the network and should've been
646 * buffered at the receiver XXX */
647 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
648 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
650 tc->fr_occurences += 1;
651 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
655 tcp_cc_congestion_undo (tcp_connection_t * tc)
657 tc->cwnd = tc->prev_cwnd;
658 tc->ssthresh = tc->prev_ssthresh;
659 tcp_cc_undo_recovery (tc);
660 ASSERT (tc->rto_boff == 0);
661 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
665 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
667 return (tcp_in_recovery (tc) && tc->rto_boff == 1
669 && tcp_opts_tstamp (&tc->rcv_opts)
670 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
674 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
676 return (tcp_cc_is_spurious_timeout_rxt (tc));
680 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
684 /* If of of the two conditions lower hold, reset dupacks because
685 * we're probably after timeout (RFC6582 heuristics).
686 * If Cumulative ack does not cover more than congestion threshold,
688 * 1) The following doesn't hold: The congestion window is greater
689 * than SMSS bytes and the difference between highest_ack
690 * and prev_highest_ack is at most 4*SMSS bytes
691 * 2) Echoed timestamp in the last non-dup ack does not equal the
694 if (seq_leq (tc->snd_una, tc->snd_congestion)
695 && ((!(tc->cwnd > tc->snd_mss
696 && tc->bytes_acked <= 4 * tc->snd_mss))
697 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
703 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
707 tcp_cc_try_recover (tcp_connection_t *tc)
709 sack_scoreboard_hole_t *hole;
712 ASSERT (tcp_in_cong_recovery (tc));
714 if (tcp_cc_is_spurious_retransmit (tc))
716 tcp_cc_congestion_undo (tc);
720 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
722 tcp_recovery_off (tc);
724 /* Previous recovery left us congested. Continue sending as part
725 * of the current recovery event with an updated snd_congestion */
726 if (tc->sack_sb.sacked_bytes && tcp_in_fastrecovery (tc))
728 tc->snd_congestion = tc->snd_nxt;
732 tc->rxt_delivered = 0;
733 tc->snd_rxt_bytes = 0;
735 tc->prr_delivered = 0;
737 tc->flags &= ~TCP_CONN_RXT_PENDING;
739 hole = scoreboard_first_hole (&tc->sack_sb);
740 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
741 scoreboard_clear (&tc->sack_sb);
743 if (tcp_in_fastrecovery (tc) && !is_spurious)
744 tcp_cc_recovered (tc);
746 tcp_fastrecovery_off (tc);
747 tcp_fastrecovery_first_off (tc);
748 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
750 ASSERT (tc->rto_boff == 0);
751 ASSERT (!tcp_in_cong_recovery (tc));
752 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
758 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
760 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
762 /* Congestion avoidance */
763 tcp_cc_rcv_ack (tc, rs);
765 /* If a cumulative ack, make sure dupacks is 0 */
770 * One function to rule them all ... and in the darkness bind them
773 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
776 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
778 /* If reneging, wait for timer based retransmits */
779 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
783 * If not in recovery, figure out if we should enter
785 if (!tcp_in_cong_recovery (tc))
790 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
791 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
793 if (tcp_should_fastrecover (tc, has_sack))
795 tcp_cc_init_congestion (tc);
798 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
800 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
801 tcp_program_retransmit (tc);
808 * Already in recovery
812 * See if we can exit and stop retransmitting
814 if (seq_geq (tc->snd_una, tc->snd_congestion))
816 /* If successfully recovered, treat ack as congestion avoidance ack
817 * and return. Otherwise, we're still congested so process feedback */
818 if (!tcp_cc_try_recover (tc))
820 tcp_cc_rcv_ack (tc, rs);
826 * Process (re)transmit feedback. Output path uses this to decide how much
827 * more data to release into the network
831 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
832 tcp_fastrecovery_first_on (tc);
834 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
835 tc->prr_delivered += rs->delivered;
841 tc->rcv_dupacks += 1;
842 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
844 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
847 tc->prr_delivered += clib_min (tc->snd_mss,
848 tc->snd_nxt - tc->snd_una);
850 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
854 /* If partial ack, assume that the first un-acked segment was lost */
855 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
856 tcp_fastrecovery_first_on (tc);
859 tcp_program_retransmit (tc);
862 * Notify cc of the event
865 if (!tc->bytes_acked)
867 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
871 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
872 * reset dupacks to 0. Also needed if in congestion recovery */
875 if (tcp_in_recovery (tc))
876 tcp_cc_rcv_ack (tc, rs);
878 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
882 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
884 if (!tcp_in_cong_recovery (tc))
887 if (tcp_opts_sack_permitted (&tc->rcv_opts))
888 tcp_rcv_sacks (tc, tc->snd_una);
892 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
893 tcp_bt_sample_delivery_rate (tc, rs);
895 tcp_cc_handle_event (tc, rs, 1);
899 * Check if duplicate ack as per RFC5681 Sec. 2
902 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
905 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
906 && seq_gt (tc->snd_nxt, tc->snd_una)
907 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
908 && (prev_snd_wnd == tc->snd_wnd));
912 * Checks if ack is a congestion control event.
915 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
916 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
918 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
919 * defined to be 'duplicate' as well */
920 *is_dack = tc->sack_sb.last_sacked_bytes
921 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
923 return (*is_dack || tcp_in_cong_recovery (tc));
927 * Process incoming ACK
930 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
931 tcp_header_t * th, u32 * error)
933 u32 prev_snd_wnd, prev_snd_una;
934 tcp_rate_sample_t rs = { 0 };
937 TCP_EVT (TCP_EVT_CC_STAT, tc);
939 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
940 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
942 /* We've probably entered recovery and the peer still has some
943 * of the data we've sent. Update snd_nxt and accept the ack */
944 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
945 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
947 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
951 tc->errors.above_ack_wnd += 1;
952 *error = TCP_ERROR_ACK_FUTURE;
953 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
957 /* If old ACK, probably it's an old dupack */
958 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
960 tc->errors.below_ack_wnd += 1;
961 *error = TCP_ERROR_ACK_OLD;
962 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
964 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
967 tcp_handle_old_ack (tc, &rs);
976 * Looks okay, process feedback
979 if (tcp_opts_sack_permitted (&tc->rcv_opts))
980 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
982 prev_snd_wnd = tc->snd_wnd;
983 prev_snd_una = tc->snd_una;
984 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
985 vnet_buffer (b)->tcp.ack_number,
986 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
987 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
988 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
989 tcp_validate_txf_size (tc, tc->bytes_acked);
991 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
992 tcp_bt_sample_delivery_rate (tc, &rs);
994 rs.delivered = tc->bytes_acked + tc->sack_sb.last_sacked_bytes -
995 tc->sack_sb.last_bytes_delivered;
997 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
999 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1000 if (tc->bytes_acked)
1001 tcp_program_dequeue (wrk, tc);
1004 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1007 * Check if we have congestion event
1010 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1012 tcp_cc_handle_event (tc, &rs, is_dack);
1013 tc->dupacks_in += is_dack;
1014 if (!tcp_in_cong_recovery (tc))
1016 *error = TCP_ERROR_ACK_OK;
1019 *error = TCP_ERROR_ACK_DUP;
1020 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1026 * Update congestion control (slow start/congestion avoidance)
1028 tcp_cc_update (tc, &rs);
1029 *error = TCP_ERROR_ACK_OK;
1034 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1036 if (!tcp_disconnect_pending (tc))
1038 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1039 tcp_disconnect_pending_on (tc);
1044 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1046 u32 thread_index, *pending_disconnects, *pending_resets;
1047 tcp_connection_t *tc;
1050 if (vec_len (wrk->pending_disconnects))
1052 thread_index = wrk->vm->thread_index;
1053 pending_disconnects = wrk->pending_disconnects;
1054 for (i = 0; i < vec_len (pending_disconnects); i++)
1056 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1057 tcp_disconnect_pending_off (tc);
1058 session_transport_closing_notify (&tc->connection);
1060 vec_set_len (wrk->pending_disconnects, 0);
1063 if (vec_len (wrk->pending_resets))
1065 thread_index = wrk->vm->thread_index;
1066 pending_resets = wrk->pending_resets;
1067 for (i = 0; i < vec_len (pending_resets); i++)
1069 tc = tcp_connection_get (pending_resets[i], thread_index);
1070 tcp_disconnect_pending_off (tc);
1071 tcp_handle_rst (tc);
1073 vec_set_len (wrk->pending_resets, 0);
1078 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1081 /* Reject out-of-order fins */
1082 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1085 /* Account for the FIN and send ack */
1087 tc->flags |= TCP_CONN_FINRCVD;
1088 tcp_program_ack (tc);
1089 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1090 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1091 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1092 tcp_program_disconnect (wrk, tc);
1093 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1094 tcp_cfg.closewait_time);
1095 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1096 *error = TCP_ERROR_FIN_RCVD;
1099 /** Enqueue data for delivery to application */
1101 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1104 int written, error = TCP_ERROR_ENQUEUED;
1106 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1108 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1109 1 /* queue event */ , 1);
1111 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1113 /* Update rcv_nxt */
1114 if (PREDICT_TRUE (written == data_len))
1116 tc->rcv_nxt += written;
1117 tc->bytes_in += written;
1119 /* If more data written than expected, account for out-of-order bytes. */
1120 else if (written > data_len)
1122 tc->rcv_nxt += written;
1123 tc->bytes_in += data_len;
1124 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1126 else if (written > 0)
1128 /* We've written something but FIFO is probably full now */
1129 tc->rcv_nxt += written;
1130 tc->bytes_in += written;
1131 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1135 /* Packet made it through for ack processing */
1136 if (tc->rcv_wnd < tc->snd_mss)
1137 return TCP_ERROR_ZERO_RWND;
1139 return TCP_ERROR_FIFO_FULL;
1142 /* Update SACK list if need be */
1143 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
1145 /* Remove SACK blocks that have been delivered */
1146 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1152 /** Enqueue out-of-order data */
1154 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1160 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1163 /* Enqueue out-of-order data with relative offset */
1164 rv = session_enqueue_stream_connection (&tc->connection, b,
1165 vnet_buffer (b)->tcp.seq_number -
1166 tc->rcv_nxt, 0 /* queue event */ ,
1169 /* Nothing written */
1172 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1173 return TCP_ERROR_FIFO_FULL;
1176 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1177 tc->bytes_in += data_len;
1179 /* Update SACK list if in use */
1180 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1182 ooo_segment_t *newest;
1185 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1187 /* Get the newest segment from the fifo */
1188 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1191 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1192 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1193 start = tc->rcv_nxt + offset;
1194 end = start + ooo_segment_length (s0->rx_fifo, newest);
1195 tcp_update_sack_list (tc, start, end);
1196 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1197 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1201 return TCP_ERROR_ENQUEUED_OOO;
1205 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1207 u32 discard, first = b->current_length;
1208 vlib_main_t *vm = vlib_get_main ();
1210 /* Handle multi-buffer segments */
1211 if (n_bytes_to_drop > b->current_length)
1213 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1217 discard = clib_min (n_bytes_to_drop, b->current_length);
1218 vlib_buffer_advance (b, discard);
1219 b = vlib_get_buffer (vm, b->next_buffer);
1220 n_bytes_to_drop -= discard;
1222 while (n_bytes_to_drop);
1223 if (n_bytes_to_drop > first)
1224 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1227 vlib_buffer_advance (b, n_bytes_to_drop);
1228 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1233 * Receive buffer for connection and handle acks
1235 * It handles both in order or out-of-order data.
1238 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1241 u32 error, n_bytes_to_drop, n_data_bytes;
1243 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1244 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1245 ASSERT (n_data_bytes);
1246 tc->data_segs_in += 1;
1248 /* Make sure we don't consume trailing bytes */
1249 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1250 b->current_length = n_data_bytes;
1252 /* Handle out-of-order data */
1253 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1255 /* Old sequence numbers allowed through because they overlapped
1257 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1259 /* Completely in the past (possible retransmit). Ack
1260 * retransmissions since we may not have any data to send */
1261 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1263 tcp_program_dupack (tc);
1264 tc->errors.below_data_wnd++;
1265 error = TCP_ERROR_SEGMENT_OLD;
1269 /* Chop off the bytes in the past and see if what is left
1270 * can be enqueued in order */
1271 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1272 n_data_bytes -= n_bytes_to_drop;
1273 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1274 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1276 error = TCP_ERROR_SEGMENT_OLD;
1282 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1283 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1284 tcp_program_dupack (tc);
1285 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1286 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1287 tc->rcv_las + tc->rcv_wnd);
1293 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1294 * segments can be enqueued after fifo tail offset changes. */
1295 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1296 tcp_program_ack (tc);
1304 tcp_header_t tcp_header;
1305 tcp_connection_t tcp_connection;
1309 format_tcp_rx_trace (u8 * s, va_list * args)
1311 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1312 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1313 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1314 tcp_connection_t *tc = &t->tcp_connection;
1315 u32 indent = format_get_indent (s);
1317 if (!tc->c_lcl_port)
1318 s = format (s, "no tcp connection\n%U%U", format_white_space, indent,
1319 format_tcp_header, &t->tcp_header, 128);
1321 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1322 format_tcp_state, tc->state, format_white_space, indent,
1323 format_tcp_header, &t->tcp_header, 128);
1329 format_tcp_rx_trace_short (u8 * s, va_list * args)
1331 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1332 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1333 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1335 s = format (s, "%d -> %d (%U)",
1336 clib_net_to_host_u16 (t->tcp_header.dst_port),
1337 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1338 t->tcp_connection.state);
1344 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1345 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1349 clib_memcpy_fast (&t0->tcp_connection, tc0,
1350 sizeof (t0->tcp_connection));
1354 th0 = tcp_buffer_hdr (b0);
1356 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1360 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1361 vlib_frame_t * frame, u8 is_ip4)
1365 n_left = frame->n_vectors;
1366 from = vlib_frame_vector_args (frame);
1370 tcp_connection_t *tc0;
1377 b0 = vlib_get_buffer (vm, bi0);
1379 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1381 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1382 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1384 th0 = tcp_buffer_hdr (b0);
1385 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1394 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1395 vlib_frame_t * frame, int is_ip4)
1397 u32 thread_index = vm->thread_index, n_left_from, *from;
1398 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1399 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1400 u16 err_counters[TCP_N_ERROR] = { 0 };
1402 if (node->flags & VLIB_NODE_FLAG_TRACE)
1403 tcp_established_trace_frame (vm, node, frame, is_ip4);
1405 from = vlib_frame_vector_args (frame);
1406 n_left_from = frame->n_vectors;
1408 vlib_get_buffers (vm, from, bufs, n_left_from);
1411 while (n_left_from > 0)
1413 u32 error = TCP_ERROR_ACK_OK;
1414 tcp_connection_t *tc;
1417 if (n_left_from > 1)
1419 vlib_prefetch_buffer_header (b[1], LOAD);
1420 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1423 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1426 if (PREDICT_FALSE (tc == 0))
1428 error = TCP_ERROR_INVALID_CONNECTION;
1432 th = tcp_buffer_hdr (b[0]);
1434 /* TODO header prediction fast path */
1436 /* 1-4: check SEQ, RST, SYN */
1437 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1439 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1443 /* 5: check the ACK field */
1444 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1447 /* 6: check the URG bit TODO */
1449 /* 7: process the segment text */
1450 if (vnet_buffer (b[0])->tcp.data_len)
1451 error = tcp_segment_rcv (wrk, tc, b[0]);
1453 /* 8: check the FIN bit */
1454 if (PREDICT_FALSE (tcp_is_fin (th)))
1455 tcp_rcv_fin (wrk, tc, b[0], &error);
1458 tcp_inc_err_counter (err_counters, error, 1);
1464 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
1465 tcp_store_err_counters (established, err_counters);
1466 tcp_handle_postponed_dequeues (wrk);
1467 tcp_handle_disconnects (wrk);
1468 vlib_buffer_free (vm, from, frame->n_vectors);
1470 return frame->n_vectors;
1473 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1474 vlib_node_runtime_t * node,
1475 vlib_frame_t * from_frame)
1477 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1480 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1481 vlib_node_runtime_t * node,
1482 vlib_frame_t * from_frame)
1484 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1488 VLIB_REGISTER_NODE (tcp4_established_node) = {
1489 .name = "tcp4-established",
1490 /* Takes a vector of packets. */
1491 .vector_size = sizeof (u32),
1492 .n_errors = TCP_N_ERROR,
1493 .error_counters = tcp_input_error_counters,
1494 .format_trace = format_tcp_rx_trace_short,
1499 VLIB_REGISTER_NODE (tcp6_established_node) = {
1500 .name = "tcp6-established",
1501 /* Takes a vector of packets. */
1502 .vector_size = sizeof (u32),
1503 .n_errors = TCP_N_ERROR,
1504 .error_counters = tcp_input_error_counters,
1505 .format_trace = format_tcp_rx_trace_short,
1511 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1514 transport_connection_t *tmp = 0;
1521 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1524 u8 is_ip_valid = 0, val_l, val_r;
1526 if (tc->connection.is_ip4)
1528 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1530 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1531 &tc->connection.lcl_ip.ip4);
1532 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1533 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1534 &tc->connection.rmt_ip.ip4);
1535 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1536 is_ip_valid = val_l && val_r;
1540 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1542 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1543 &tc->connection.lcl_ip.ip6);
1544 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1545 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1546 &tc->connection.rmt_ip.ip6);
1547 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1548 is_ip_valid = val_l && val_r;
1551 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1552 && (tc->state == TCP_STATE_LISTEN
1553 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1557 handle = session_lookup_half_open_handle (&tc->connection);
1558 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1559 tc->c_proto, tc->c_is_ip4);
1563 if (tmp->lcl_port == hdr->dst_port
1564 && tmp->rmt_port == hdr->src_port)
1566 TCP_DBG ("half-open is valid!");
1575 * Lookup transport connection
1577 static tcp_connection_t *
1578 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1582 transport_connection_t *tconn;
1583 tcp_connection_t *tc;
1588 ip4 = vlib_buffer_get_current (b);
1589 tcp = ip4_next_header (ip4);
1590 tconn = session_lookup_connection_wt4 (fib_index,
1595 TRANSPORT_PROTO_TCP,
1596 thread_index, &is_filtered);
1597 tc = tcp_get_connection_from_transport (tconn);
1598 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1603 ip6 = vlib_buffer_get_current (b);
1604 tcp = ip6_next_header (ip6);
1605 tconn = session_lookup_connection_wt6 (fib_index,
1610 TRANSPORT_PROTO_TCP,
1611 thread_index, &is_filtered);
1612 tc = tcp_get_connection_from_transport (tconn);
1613 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1618 static tcp_connection_t *
1619 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1625 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1626 tcp_header_t *tcp = tcp_buffer_hdr (b);
1627 s = session_lookup_listener4 (fib_index,
1629 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1633 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1634 tcp_header_t *tcp = tcp_buffer_hdr (b);
1635 s = session_lookup_listener6 (fib_index,
1637 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1640 if (PREDICT_TRUE (s != 0))
1641 return tcp_get_connection_from_transport (transport_get_listener
1642 (TRANSPORT_PROTO_TCP,
1643 s->connection_index));
1649 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1650 u32 *from, u32 n_bufs)
1652 tcp_connection_t *tc = 0;
1657 for (i = 0; i < n_bufs; i++)
1659 b = vlib_get_buffer (vm, from[i]);
1660 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1663 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1664 t = vlib_add_trace (vm, node, b, sizeof (*t));
1665 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1670 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1672 vnet_main_t *vnm = vnet_get_main ();
1673 const dpo_id_t *dpo;
1674 const load_balance_t *lb;
1675 vnet_hw_interface_t *hw_if;
1676 u32 sw_if_idx, lb_idx;
1680 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1681 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1685 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1686 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1689 lb = load_balance_get (lb_idx);
1690 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1692 dpo = load_balance_get_bucket_i (lb, 0);
1694 sw_if_idx = dpo_get_urpf (dpo);
1695 if (PREDICT_FALSE (sw_if_idx == ~0))
1698 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1699 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1700 tc->cfg_flags |= TCP_CFG_F_TSO;
1704 tcp_input_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1705 vlib_buffer_t **bs, u16 *nexts, u32 n_bufs, u8 is_ip4)
1707 tcp_connection_t *tc;
1713 for (i = 0; i < n_bufs; i++)
1715 if (!(bs[i]->flags & VLIB_BUFFER_IS_TRACED))
1718 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
1719 if (nexts[i] == TCP_INPUT_NEXT_DROP || nexts[i] == TCP_INPUT_NEXT_PUNT ||
1720 nexts[i] == TCP_INPUT_NEXT_RESET)
1726 flags = vnet_buffer (bs[i])->tcp.flags;
1728 if (flags == TCP_STATE_LISTEN)
1729 tc = tcp_listener_get (vnet_buffer (bs[i])->tcp.connection_index);
1730 else if (flags == TCP_STATE_SYN_SENT)
1731 tc = tcp_half_open_connection_get (
1732 vnet_buffer (bs[i])->tcp.connection_index);
1734 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
1737 tcp = tcp_buffer_hdr (bs[i]);
1738 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
1743 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1744 vlib_frame_t *frame, int is_ip4)
1746 u32 n_left_from, *from, thread_index = vm->thread_index;
1747 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1748 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1750 from = vlib_frame_vector_args (frame);
1751 n_left_from = frame->n_vectors;
1753 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1754 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1756 vlib_get_buffers (vm, from, bufs, n_left_from);
1759 while (n_left_from > 0)
1761 u32 ack, seq, error = TCP_ERROR_NONE;
1762 tcp_connection_t *tc, *new_tc;
1765 tc = tcp_half_open_connection_get (
1766 vnet_buffer (b[0])->tcp.connection_index);
1767 if (PREDICT_FALSE (tc == 0))
1769 error = TCP_ERROR_INVALID_CONNECTION;
1773 /* Half-open completed or cancelled recently but the connection
1774 * was't removed yet by the owning thread */
1775 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1777 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1781 ack = vnet_buffer (b[0])->tcp.ack_number;
1782 seq = vnet_buffer (b[0])->tcp.seq_number;
1783 tcp = tcp_buffer_hdr (b[0]);
1785 /* Crude check to see if the connection handle does not match
1786 * the packet. Probably connection just switched to established */
1787 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1788 tcp->src_port != tc->c_rmt_port))
1790 error = TCP_ERROR_INVALID_CONNECTION;
1794 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1796 error = TCP_ERROR_SEGMENT_INVALID;
1800 /* SYNs consume sequence numbers */
1801 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1804 * 1. check the ACK bit
1808 * If the ACK bit is set
1809 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1810 * the RST bit is set, if so drop the segment and return)
1811 * <SEQ=SEG.ACK><CTL=RST>
1812 * and discard the segment. Return.
1813 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1817 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1820 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1821 error = TCP_ERROR_RCV_WND;
1825 /* Make sure ACK is valid */
1826 if (seq_gt (tc->snd_una, ack))
1828 error = TCP_ERROR_ACK_INVALID;
1834 * 2. check the RST bit
1839 /* If ACK is acceptable, signal client that peer is not
1840 * willing to accept connection and drop connection*/
1842 tcp_rcv_rst (wrk, tc);
1843 error = TCP_ERROR_RST_RCVD;
1848 * 3. check the security and precedence (skipped)
1852 * 4. check the SYN bit
1855 /* No SYN flag. Drop. */
1858 error = TCP_ERROR_SEGMENT_INVALID;
1863 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1865 error = TCP_ERROR_OPTIONS;
1869 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1870 * current thread pool. */
1871 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1872 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1874 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1876 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1878 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1879 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1882 if (tcp_opts_wscale (&new_tc->rcv_opts))
1883 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1885 new_tc->rcv_wscale = 0;
1887 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1888 << new_tc->snd_wscale;
1889 new_tc->snd_wl1 = seq;
1890 new_tc->snd_wl2 = ack;
1892 tcp_connection_init_vars (new_tc);
1894 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1895 if (PREDICT_TRUE (tcp_ack (tcp)))
1897 /* Our SYN is ACKed: we have iss < ack = snd_una */
1899 /* TODO Dequeue acknowledged segments if we support Fast Open */
1900 new_tc->snd_una = ack;
1901 new_tc->state = TCP_STATE_ESTABLISHED;
1903 /* Make sure las is initialized for the wnd computation */
1904 new_tc->rcv_las = new_tc->rcv_nxt;
1906 /* Notify app that we have connection. If session layer can't
1907 * allocate session send reset */
1908 if (session_stream_connect_notify (&new_tc->connection,
1911 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1912 tcp_connection_cleanup (new_tc);
1913 error = TCP_ERROR_CREATE_SESSION_FAIL;
1917 transport_fifos_init_ooo (&new_tc->connection);
1918 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1919 /* Update rtt with the syn-ack sample */
1920 tcp_estimate_initial_rtt (new_tc);
1921 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1922 error = TCP_ERROR_SYN_ACKS_RCVD;
1924 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1927 new_tc->state = TCP_STATE_SYN_RCVD;
1929 /* Notify app that we have connection */
1930 if (session_stream_connect_notify (&new_tc->connection,
1933 tcp_connection_cleanup (new_tc);
1934 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1935 TCP_EVT (TCP_EVT_RST_SENT, tc);
1936 error = TCP_ERROR_CREATE_SESSION_FAIL;
1940 transport_fifos_init_ooo (&new_tc->connection);
1941 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1943 tcp_init_snd_vars (new_tc);
1944 tcp_send_synack (new_tc);
1945 error = TCP_ERROR_SYNS_RCVD;
1949 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
1950 tcp_check_tx_offload (new_tc, is_ip4);
1952 /* Read data, if any */
1953 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
1955 clib_warning ("rcvd data in syn-sent");
1956 error = tcp_segment_rcv (wrk, new_tc, b[0]);
1957 if (error == TCP_ERROR_ACK_OK)
1958 error = TCP_ERROR_SYN_ACKS_RCVD;
1962 /* Send ack now instead of programming it because connection was
1963 * just established and it's not optional. */
1964 tcp_send_ack (new_tc);
1969 /* If this is not the owning thread, wait for syn retransmit to
1970 * expire and cleanup then */
1971 if (tcp_half_open_connection_cleanup (tc))
1972 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
1978 tcp_inc_counter (syn_sent, error, 1);
1981 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
1982 vlib_buffer_free (vm, from, frame->n_vectors);
1983 tcp_handle_disconnects (wrk);
1985 return frame->n_vectors;
1988 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
1989 vlib_node_runtime_t * node,
1990 vlib_frame_t * from_frame)
1992 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1995 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
1996 vlib_node_runtime_t * node,
1997 vlib_frame_t * from_frame)
1999 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2003 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2005 .name = "tcp4-syn-sent",
2006 /* Takes a vector of packets. */
2007 .vector_size = sizeof (u32),
2008 .n_errors = TCP_N_ERROR,
2009 .error_counters = tcp_input_error_counters,
2010 .format_trace = format_tcp_rx_trace_short,
2015 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2017 .name = "tcp6-syn-sent",
2018 /* Takes a vector of packets. */
2019 .vector_size = sizeof (u32),
2020 .n_errors = TCP_N_ERROR,
2021 .error_counters = tcp_input_error_counters,
2022 .format_trace = format_tcp_rx_trace_short,
2027 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2028 u32 *from, u32 n_bufs)
2030 u32 thread_index = vm->thread_index;
2031 tcp_connection_t *tc = 0;
2036 for (i = 0; i < n_bufs; i++)
2038 b = vlib_get_buffer (vm, from[i]);
2039 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2041 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2043 t = vlib_add_trace (vm, node, b, sizeof (*t));
2044 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2049 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2050 * as per RFC793 p. 64
2053 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2054 vlib_frame_t *frame, int is_ip4)
2056 u32 thread_index = vm->thread_index, n_left_from, *from, max_deq;
2057 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2058 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2060 from = vlib_frame_vector_args (frame);
2061 n_left_from = frame->n_vectors;
2063 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2064 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2066 vlib_get_buffers (vm, from, bufs, n_left_from);
2069 while (n_left_from > 0)
2071 u32 error = TCP_ERROR_NONE;
2072 tcp_header_t *tcp = 0;
2073 tcp_connection_t *tc;
2076 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2078 if (PREDICT_FALSE (tc == 0))
2080 error = TCP_ERROR_INVALID_CONNECTION;
2084 tcp = tcp_buffer_hdr (b[0]);
2085 is_fin = tcp_is_fin (tcp);
2089 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2091 tcp_connection_t *tmp;
2092 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2094 if (tmp->state != tc->state)
2096 if (tc->state != TCP_STATE_CLOSED)
2097 clib_warning ("state changed");
2104 * Special treatment for CLOSED
2106 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2108 error = TCP_ERROR_CONNECTION_CLOSED;
2113 * For all other states (except LISTEN)
2116 /* 1-4: check SEQ, RST, SYN */
2117 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2120 /* 5: check the ACK field */
2123 case TCP_STATE_SYN_RCVD:
2125 /* Make sure the segment is exactly right */
2126 if (tc->rcv_nxt != vnet_buffer (b[0])->tcp.seq_number)
2128 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2129 error = TCP_ERROR_SEGMENT_INVALID;
2134 * If the segment acknowledgment is not acceptable, form a
2136 * <SEQ=SEG.ACK><CTL=RST>
2139 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2141 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2142 error = TCP_ERROR_SEGMENT_INVALID;
2146 /* Avoid notifying app if connection is about to be closed */
2147 if (PREDICT_FALSE (is_fin))
2150 /* Update rtt and rto */
2151 tcp_estimate_initial_rtt (tc);
2152 tcp_connection_tx_pacer_update (tc);
2154 /* Switch state to ESTABLISHED */
2155 tc->state = TCP_STATE_ESTABLISHED;
2156 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2158 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2159 tcp_check_tx_offload (tc, is_ip4);
2161 /* Initialize session variables */
2162 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2163 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2164 << tc->rcv_opts.wscale;
2165 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2166 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2168 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2169 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2170 if (session_stream_accept_notify (&tc->connection))
2172 error = TCP_ERROR_MSG_QUEUE_FULL;
2173 tcp_send_reset (tc);
2174 session_transport_delete_notify (&tc->connection);
2175 tcp_connection_cleanup (tc);
2178 error = TCP_ERROR_ACK_OK;
2180 case TCP_STATE_ESTABLISHED:
2181 /* We can get packets in established state here because they
2182 * were enqueued before state change */
2183 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2187 case TCP_STATE_FIN_WAIT_1:
2188 /* In addition to the processing for the ESTABLISHED state, if
2189 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2190 * continue processing in that state. */
2191 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2194 /* Still have to send the FIN */
2195 if (tc->flags & TCP_CONN_FINPNDG)
2197 /* TX fifo finally drained */
2198 max_deq = transport_max_tx_dequeue (&tc->connection);
2199 if (max_deq <= tc->burst_acked)
2201 /* If a fin was received and data was acked extend wait */
2202 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2203 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2204 tcp_cfg.closewait_time);
2206 /* If FIN is ACKed */
2207 else if (tc->snd_una == tc->snd_nxt)
2209 /* Stop all retransmit timers because we have nothing more
2211 tcp_connection_timers_reset (tc);
2213 /* We already have a FIN but didn't transition to CLOSING
2214 * because of outstanding tx data. Close the connection. */
2215 if (tc->flags & TCP_CONN_FINRCVD)
2217 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2218 session_transport_closed_notify (&tc->connection);
2219 tcp_program_cleanup (wrk, tc);
2223 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2224 /* Enable waitclose because we're willing to wait for peer's
2225 * FIN but not indefinitely. */
2226 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2227 tcp_cfg.finwait2_time);
2229 /* Don't try to deq the FIN acked */
2230 if (tc->burst_acked > 1)
2231 session_tx_fifo_dequeue_drop (&tc->connection,
2232 tc->burst_acked - 1);
2233 tc->burst_acked = 0;
2236 case TCP_STATE_FIN_WAIT_2:
2237 /* In addition to the processing for the ESTABLISHED state, if
2238 * the retransmission queue is empty, the user's CLOSE can be
2239 * acknowledged ("ok") but do not delete the TCB. */
2240 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2242 tc->burst_acked = 0;
2244 case TCP_STATE_CLOSE_WAIT:
2245 /* Do the same processing as for the ESTABLISHED state. */
2246 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2249 if (!(tc->flags & TCP_CONN_FINPNDG))
2252 /* Still have outstanding tx data */
2253 max_deq = transport_max_tx_dequeue (&tc->connection);
2254 if (max_deq > tc->burst_acked)
2258 tcp_connection_timers_reset (tc);
2259 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2260 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2261 tcp_cfg.lastack_time);
2263 case TCP_STATE_CLOSING:
2264 /* In addition to the processing for the ESTABLISHED state, if
2265 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2266 * otherwise ignore the segment. */
2267 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2270 if (tc->snd_una != tc->snd_nxt)
2273 tcp_connection_timers_reset (tc);
2274 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2275 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2276 tcp_cfg.timewait_time);
2277 session_transport_closed_notify (&tc->connection);
2281 case TCP_STATE_LAST_ACK:
2282 /* The only thing that [should] arrive in this state is an
2283 * acknowledgment of our FIN. If our FIN is now acknowledged,
2284 * delete the TCB, enter the CLOSED state, and return. */
2286 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2289 /* Apparently our ACK for the peer's FIN was lost */
2290 if (is_fin && tc->snd_una != tc->snd_nxt)
2296 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2297 session_transport_closed_notify (&tc->connection);
2299 /* Don't free the connection from the data path since
2300 * we can't ensure that we have no packets already enqueued
2301 * to output. Rely instead on the waitclose timer */
2302 tcp_connection_timers_reset (tc);
2303 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2308 case TCP_STATE_TIME_WAIT:
2309 /* The only thing that can arrive in this state is a
2310 * retransmission of the remote FIN. Acknowledge it, and restart
2311 * the 2 MSL timeout. */
2313 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2319 tcp_program_ack (tc);
2320 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2321 tcp_cfg.timewait_time);
2329 /* 6: check the URG bit TODO */
2331 /* 7: process the segment text */
2334 case TCP_STATE_ESTABLISHED:
2335 case TCP_STATE_FIN_WAIT_1:
2336 case TCP_STATE_FIN_WAIT_2:
2337 if (vnet_buffer (b[0])->tcp.data_len)
2338 error = tcp_segment_rcv (wrk, tc, b[0]);
2339 /* Don't accept out of order fins lower */
2340 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2343 case TCP_STATE_CLOSE_WAIT:
2344 case TCP_STATE_CLOSING:
2345 case TCP_STATE_LAST_ACK:
2346 case TCP_STATE_TIME_WAIT:
2347 /* This should not occur, since a FIN has been received from the
2348 * remote side. Ignore the segment text. */
2352 /* 8: check the FIN bit */
2356 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2360 case TCP_STATE_ESTABLISHED:
2361 /* Account for the FIN and send ack */
2363 tcp_program_ack (tc);
2364 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2365 tcp_program_disconnect (wrk, tc);
2366 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2367 tcp_cfg.closewait_time);
2369 case TCP_STATE_SYN_RCVD:
2370 /* Send FIN-ACK and enter TIME-WAIT, as opposed to LAST-ACK,
2371 * because the app was not notified yet and we want to avoid
2372 * session state transitions to ensure cleanup does not
2373 * propagate to app. */
2374 tcp_connection_timers_reset (tc);
2377 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2378 tcp_program_cleanup (wrk, tc);
2380 case TCP_STATE_CLOSE_WAIT:
2381 case TCP_STATE_CLOSING:
2382 case TCP_STATE_LAST_ACK:
2385 case TCP_STATE_FIN_WAIT_1:
2388 if (tc->flags & TCP_CONN_FINPNDG)
2390 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2391 * sending it. Since we already received a fin, do not wait
2393 tc->flags |= TCP_CONN_FINRCVD;
2394 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2395 tcp_cfg.closewait_time);
2399 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2400 tcp_program_ack (tc);
2401 /* Wait for ACK for our FIN but not forever */
2402 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2403 tcp_cfg.closing_time);
2406 case TCP_STATE_FIN_WAIT_2:
2407 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2409 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2410 tcp_connection_timers_reset (tc);
2411 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2412 tcp_cfg.timewait_time);
2413 tcp_program_ack (tc);
2414 session_transport_closed_notify (&tc->connection);
2416 case TCP_STATE_TIME_WAIT:
2417 /* Remain in the TIME-WAIT state. Restart the time-wait
2420 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2421 tcp_cfg.timewait_time);
2424 error = TCP_ERROR_FIN_RCVD;
2430 tcp_inc_counter (rcv_process, error, 1);
2433 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2434 tcp_handle_postponed_dequeues (wrk);
2435 tcp_handle_disconnects (wrk);
2436 vlib_buffer_free (vm, from, frame->n_vectors);
2438 return frame->n_vectors;
2441 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2442 vlib_node_runtime_t * node,
2443 vlib_frame_t * from_frame)
2445 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2448 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2449 vlib_node_runtime_t * node,
2450 vlib_frame_t * from_frame)
2452 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2456 VLIB_REGISTER_NODE (tcp4_rcv_process_node) = {
2457 .name = "tcp4-rcv-process",
2458 /* Takes a vector of packets. */
2459 .vector_size = sizeof (u32),
2460 .n_errors = TCP_N_ERROR,
2461 .error_counters = tcp_input_error_counters,
2462 .format_trace = format_tcp_rx_trace_short,
2467 VLIB_REGISTER_NODE (tcp6_rcv_process_node) = {
2468 .name = "tcp6-rcv-process",
2469 /* Takes a vector of packets. */
2470 .vector_size = sizeof (u32),
2471 .n_errors = TCP_N_ERROR,
2472 .error_counters = tcp_input_error_counters,
2473 .format_trace = format_tcp_rx_trace_short,
2478 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2479 u32 *to_next, u32 n_bufs)
2481 tcp_connection_t *tc = 0;
2486 for (i = 0; i < n_bufs; i++)
2488 b = vlib_get_buffer (vm, to_next[i]);
2489 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2491 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2492 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2493 t = vlib_add_trace (vm, node, b, sizeof (*t));
2494 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2499 * SYN received in TIME-WAIT state.
2502 * "When a connection is [...] on TIME-WAIT state [...]
2503 * [a TCP] MAY accept a new SYN from the remote TCP to
2504 * reopen the connection directly, if it:
2506 * (1) assigns its initial sequence number for the new
2507 * connection to be larger than the largest sequence
2508 * number it used on the previous connection incarnation,
2511 * (2) returns to TIME-WAIT state if the SYN turns out
2512 * to be an old duplicate".
2514 * The function returns true if the syn can be accepted during
2515 * connection time-wait (port reuse). In this case the function
2516 * also calculates what the iss should be for the new connection.
2519 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2521 int paws_reject = tcp_segment_check_paws (tc);
2525 /* Check that the SYN arrived out of window. We accept it */
2527 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2528 (tcp_opts_tstamp (&tc->rcv_opts) &&
2529 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2531 /* Set the iss of the new connection to be the largest sequence number
2532 * the old peer would have accepted and add some random number
2534 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2535 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2545 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2546 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2547 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2548 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2554 * LISTEN state processing as per RFC 793 p. 65
2557 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2558 vlib_frame_t *frame, int is_ip4)
2560 u32 n_left_from, *from, n_syns = 0;
2561 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2562 u32 thread_index = vm->thread_index;
2565 from = vlib_frame_vector_args (frame);
2566 n_left_from = frame->n_vectors;
2568 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2569 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2571 vlib_get_buffers (vm, from, bufs, n_left_from);
2574 while (n_left_from > 0)
2576 tcp_connection_t *lc, *child;
2578 /* Flags initialized with connection state after lookup */
2579 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2581 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2583 /* Probably we are in time-wait or closed state */
2586 tcp_connection_t *tc;
2587 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2589 if (tc->state != TCP_STATE_TIME_WAIT)
2591 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2595 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2597 /* This SYN can't be accepted */
2598 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2602 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2603 /* clean up the old session */
2604 tcp_connection_del (tc);
2605 /* listener was cleaned up */
2608 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
2613 /* Make sure connection wasn't just created */
2615 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2616 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2618 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2622 /* Create child session. For syn-flood protection use filter */
2624 /* 1. first check for an RST: handled by input dispatch */
2626 /* 2. second check for an ACK: handled by input dispatch */
2628 /* 3. check for a SYN (did that already) */
2630 /* Create child session and send SYN-ACK */
2631 child = tcp_connection_alloc (thread_index);
2633 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2635 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
2636 tcp_connection_free (child);
2640 tcp_init_w_buffer (child, b[0], is_ip4);
2642 child->state = TCP_STATE_SYN_RCVD;
2643 child->c_fib_index = lc->c_fib_index;
2644 child->cc_algo = lc->cc_algo;
2646 /* In the regular case, the tw_iss will be zero, but
2647 * in the special case of syn arriving in time_wait state, the value
2648 * will be set according to rfc 1122
2650 child->iss = tw_iss;
2651 tcp_connection_init_vars (child);
2652 child->rto = TCP_RTO_MIN;
2655 * This initializes elog track, must be done before synack.
2656 * We also do it before possible tcp_connection_cleanup() as it
2657 * generates TCP_EVT_DELETE event.
2659 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2661 if (session_stream_accept (&child->connection, lc->c_s_index,
2662 lc->c_thread_index, 0 /* notify */ ))
2664 tcp_connection_cleanup (child);
2665 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
2669 transport_fifos_init_ooo (&child->connection);
2670 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2672 tcp_send_synack (child);
2680 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2681 vlib_buffer_free (vm, from, frame->n_vectors);
2683 return frame->n_vectors;
2686 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2687 vlib_frame_t * from_frame)
2689 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2692 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2693 vlib_frame_t * from_frame)
2695 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2699 VLIB_REGISTER_NODE (tcp4_listen_node) = {
2700 .name = "tcp4-listen",
2701 /* Takes a vector of packets. */
2702 .vector_size = sizeof (u32),
2703 .n_errors = TCP_N_ERROR,
2704 .error_counters = tcp_input_error_counters,
2705 .format_trace = format_tcp_rx_trace_short,
2710 VLIB_REGISTER_NODE (tcp6_listen_node) = {
2711 .name = "tcp6-listen",
2712 /* Takes a vector of packets. */
2713 .vector_size = sizeof (u32),
2714 .n_errors = TCP_N_ERROR,
2715 .error_counters = tcp_input_error_counters,
2716 .format_trace = format_tcp_rx_trace_short,
2721 tcp46_drop_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2722 vlib_frame_t *frame, int is_ip4)
2724 u32 *from = vlib_frame_vector_args (frame);
2726 /* Error counters must be incremented by previous nodes */
2727 vlib_buffer_free (vm, from, frame->n_vectors);
2729 return frame->n_vectors;
2732 VLIB_NODE_FN (tcp4_drop_node)
2733 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2735 return tcp46_drop_inline (vm, node, from_frame, 1 /* is_ip4 */);
2738 VLIB_NODE_FN (tcp6_drop_node)
2739 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2741 return tcp46_drop_inline (vm, node, from_frame, 0 /* is_ip4 */);
2744 VLIB_REGISTER_NODE (tcp4_drop_node) = {
2745 .name = "tcp4-drop",
2746 .vector_size = sizeof (u32),
2747 .n_errors = TCP_N_ERROR,
2748 .error_counters = tcp_input_error_counters,
2751 VLIB_REGISTER_NODE (tcp6_drop_node) = {
2752 .name = "tcp6-drop",
2753 .vector_size = sizeof (u32),
2754 .n_errors = TCP_N_ERROR,
2755 .error_counters = tcp_input_error_counters,
2758 #define foreach_tcp4_input_next \
2759 _ (DROP, "tcp4-drop") \
2760 _ (LISTEN, "tcp4-listen") \
2761 _ (RCV_PROCESS, "tcp4-rcv-process") \
2762 _ (SYN_SENT, "tcp4-syn-sent") \
2763 _ (ESTABLISHED, "tcp4-established") \
2764 _ (RESET, "tcp4-reset") \
2765 _ (PUNT, "ip4-punt")
2767 #define foreach_tcp6_input_next \
2768 _ (DROP, "tcp6-drop") \
2769 _ (LISTEN, "tcp6-listen") \
2770 _ (RCV_PROCESS, "tcp6-rcv-process") \
2771 _ (SYN_SENT, "tcp6-syn-sent") \
2772 _ (ESTABLISHED, "tcp6-established") \
2773 _ (RESET, "tcp6-reset") \
2774 _ (PUNT, "ip6-punt")
2776 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2779 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2781 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2783 *next = TCP_INPUT_NEXT_DROP;
2785 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2787 *next = TCP_INPUT_NEXT_PUNT;
2788 *error = TCP_ERROR_PUNT;
2792 *next = TCP_INPUT_NEXT_RESET;
2793 *error = TCP_ERROR_NO_LISTENER;
2798 tcp_input_dispatch_buffer (tcp_main_t *tm, tcp_connection_t *tc,
2799 vlib_buffer_t *b, u16 *next, u16 *err_counters)
2805 tcp = tcp_buffer_hdr (b);
2806 flags = tcp->flags & filter_flags;
2807 *next = tm->dispatch_table[tc->state][flags].next;
2808 error = tm->dispatch_table[tc->state][flags].error;
2811 /* Track connection state when packet was received. It is required
2812 * for @ref tcp46_listen_inline to detect whether we reached
2813 * the node as a result of a SYN packet received while in time-wait
2814 * state. In this case the connection_index in vnet buffer will point
2815 * to the existing tcp connection and not the listener
2817 vnet_buffer (b)->tcp.flags = tc->state;
2819 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2821 tcp_inc_err_counter (err_counters, error, 1);
2822 if (error == TCP_ERROR_DISPATCH)
2823 clib_warning ("tcp conn %u disp error state %U flags %U",
2824 tc->c_c_index, format_tcp_state, tc->state,
2825 format_tcp_flags, (int) flags);
2830 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2831 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2833 u32 n_left_from, *from, thread_index = vm->thread_index;
2834 tcp_main_t *tm = vnet_get_tcp_main ();
2835 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2836 u16 nexts[VLIB_FRAME_SIZE], *next;
2837 u16 err_counters[TCP_N_ERROR] = { 0 };
2839 tcp_update_time_now (tcp_get_worker (thread_index));
2841 from = vlib_frame_vector_args (frame);
2842 n_left_from = frame->n_vectors;
2843 vlib_get_buffers (vm, from, bufs, n_left_from);
2848 while (n_left_from >= 4)
2850 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2851 tcp_connection_t *tc0, *tc1;
2854 vlib_prefetch_buffer_header (b[2], STORE);
2855 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2857 vlib_prefetch_buffer_header (b[3], STORE);
2858 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2861 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2863 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2865 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2868 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2870 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2871 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2873 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2874 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2876 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2877 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], err_counters);
2881 if (PREDICT_TRUE (tc0 != 0))
2883 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2884 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2885 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0],
2890 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2891 tcp_inc_err_counter (err_counters, error0, 1);
2894 if (PREDICT_TRUE (tc1 != 0))
2896 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2897 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2898 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1],
2903 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2904 tcp_inc_err_counter (err_counters, error1, 1);
2912 while (n_left_from > 0)
2914 tcp_connection_t *tc0;
2915 u32 error0 = TCP_ERROR_NO_LISTENER;
2917 if (n_left_from > 1)
2919 vlib_prefetch_buffer_header (b[1], STORE);
2920 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2923 next[0] = TCP_INPUT_NEXT_DROP;
2924 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2926 if (PREDICT_TRUE (tc0 != 0))
2928 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2929 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2930 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2934 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2935 tcp_inc_err_counter (err_counters, error0, 1);
2943 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2944 tcp_input_trace_frame (vm, node, bufs, nexts, frame->n_vectors, is_ip4);
2946 tcp_store_err_counters (input, err_counters);
2947 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2948 return frame->n_vectors;
2951 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2952 vlib_node_runtime_t * node,
2953 vlib_frame_t * from_frame)
2955 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2956 1 /* is_nolookup */ );
2959 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2960 vlib_node_runtime_t * node,
2961 vlib_frame_t * from_frame)
2963 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2964 1 /* is_nolookup */ );
2968 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2970 .name = "tcp4-input-nolookup",
2971 /* Takes a vector of packets. */
2972 .vector_size = sizeof (u32),
2973 .n_errors = TCP_N_ERROR,
2974 .error_counters = tcp_input_error_counters,
2975 .n_next_nodes = TCP_INPUT_N_NEXT,
2978 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2979 foreach_tcp4_input_next
2982 .format_buffer = format_tcp_header,
2983 .format_trace = format_tcp_rx_trace,
2988 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2990 .name = "tcp6-input-nolookup",
2991 /* Takes a vector of packets. */
2992 .vector_size = sizeof (u32),
2993 .n_errors = TCP_N_ERROR,
2994 .error_counters = tcp_input_error_counters,
2995 .n_next_nodes = TCP_INPUT_N_NEXT,
2998 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2999 foreach_tcp6_input_next
3002 .format_buffer = format_tcp_header,
3003 .format_trace = format_tcp_rx_trace,
3007 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3008 vlib_frame_t * from_frame)
3010 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3011 0 /* is_nolookup */ );
3014 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3015 vlib_frame_t * from_frame)
3017 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3018 0 /* is_nolookup */ );
3022 VLIB_REGISTER_NODE (tcp4_input_node) =
3024 .name = "tcp4-input",
3025 /* Takes a vector of packets. */
3026 .vector_size = sizeof (u32),
3027 .n_errors = TCP_N_ERROR,
3028 .error_counters = tcp_input_error_counters,
3029 .n_next_nodes = TCP_INPUT_N_NEXT,
3032 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3033 foreach_tcp4_input_next
3036 .format_buffer = format_tcp_header,
3037 .format_trace = format_tcp_rx_trace,
3042 VLIB_REGISTER_NODE (tcp6_input_node) =
3044 .name = "tcp6-input",
3045 /* Takes a vector of packets. */
3046 .vector_size = sizeof (u32),
3047 .n_errors = TCP_N_ERROR,
3048 .error_counters = tcp_input_error_counters,
3049 .n_next_nodes = TCP_INPUT_N_NEXT,
3052 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3053 foreach_tcp6_input_next
3056 .format_buffer = format_tcp_header,
3057 .format_trace = format_tcp_rx_trace,
3061 #ifndef CLIB_MARCH_VARIANT
3063 tcp_check_gso (tcp_connection_t *tc)
3065 tcp_check_tx_offload (tc, tc->c_is_ip4);
3069 tcp_dispatch_table_init (tcp_main_t * tm)
3072 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3073 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3075 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3076 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3079 #define _(t,f,n,e) \
3081 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3082 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3085 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3086 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3087 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3088 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3089 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3090 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3091 TCP_ERROR_ACK_INVALID);
3092 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3093 TCP_ERROR_SEGMENT_INVALID);
3094 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3095 TCP_ERROR_SEGMENT_INVALID);
3096 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3097 TCP_ERROR_INVALID_CONNECTION);
3098 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3099 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3100 TCP_ERROR_SEGMENT_INVALID);
3101 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3102 TCP_ERROR_SEGMENT_INVALID);
3103 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3104 TCP_ERROR_SEGMENT_INVALID);
3105 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3106 TCP_ERROR_SEGMENT_INVALID);
3107 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3108 TCP_ERROR_SEGMENT_INVALID);
3109 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3110 TCP_ERROR_SEGMENT_INVALID);
3111 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3112 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3113 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3114 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3115 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3116 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3118 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3119 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3121 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3123 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3124 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3125 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3126 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3128 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3130 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3131 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3132 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3134 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3135 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3136 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3137 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3138 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3139 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3140 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3141 /* SYN-ACK for a SYN */
3142 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3144 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3145 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3146 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3148 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3149 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3151 /* ACK for for established connection -> tcp-established. */
3152 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3153 /* FIN for for established connection -> tcp-established. */
3154 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3155 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3157 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3159 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3160 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3161 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3163 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3164 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3165 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3166 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3167 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3168 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3169 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3170 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3172 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3173 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3175 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3177 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3178 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3179 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3180 /* ACK or FIN-ACK to our FIN */
3181 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3182 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3184 /* FIN in reply to our FIN from the other side */
3185 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3186 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3187 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3189 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3190 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3191 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3192 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3193 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3194 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3195 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3197 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3198 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3199 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3200 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3202 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3204 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3205 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3206 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3207 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3209 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3210 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3211 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3212 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3214 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3216 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3217 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3218 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3221 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3226 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3227 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3230 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3231 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3232 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3233 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3235 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3236 /* FIN confirming that the peer (app) has closed */
3237 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3238 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3239 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3241 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3242 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3244 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3245 _ (FIN_WAIT_2, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3247 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3248 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3250 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3251 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3253 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3254 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3255 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3256 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3257 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3259 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3261 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3262 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3263 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3265 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3266 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3267 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3268 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3269 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3270 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3271 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3272 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3274 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3275 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3277 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3279 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3280 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3281 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3282 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3283 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3285 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3286 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3288 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3289 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3290 * incoming segment not containing a RST causes a RST to be sent in
3292 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3293 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3294 TCP_ERROR_CONNECTION_CLOSED);
3295 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3296 _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3297 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3298 TCP_ERROR_CONNECTION_CLOSED);
3302 static clib_error_t *
3303 tcp_input_init (vlib_main_t * vm)
3305 clib_error_t *error = 0;
3306 tcp_main_t *tm = vnet_get_tcp_main ();
3308 if ((error = vlib_call_init_function (vm, tcp_init)))
3311 /* Initialize dispatch table. */
3312 tcp_dispatch_table_init (tm);
3317 VLIB_INIT_FUNCTION (tcp_input_init);
3319 #endif /* CLIB_MARCH_VARIANT */
3322 * fd.io coding-style-patch-verification: ON
3325 * eval: (c-set-style "gnu")