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, errors = 0;
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 };
1401 u32 n_left_from, *from;
1403 if (node->flags & VLIB_NODE_FLAG_TRACE)
1404 tcp_established_trace_frame (vm, node, frame, is_ip4);
1406 from = vlib_frame_vector_args (frame);
1407 n_left_from = frame->n_vectors;
1409 vlib_get_buffers (vm, from, bufs, n_left_from);
1412 while (n_left_from > 0)
1414 u32 error = TCP_ERROR_ACK_OK;
1415 tcp_connection_t *tc;
1418 if (n_left_from > 1)
1420 vlib_prefetch_buffer_header (b[1], LOAD);
1421 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1424 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1427 if (PREDICT_FALSE (tc == 0))
1429 error = TCP_ERROR_INVALID_CONNECTION;
1433 th = tcp_buffer_hdr (b[0]);
1435 /* TODO header prediction fast path */
1437 /* 1-4: check SEQ, RST, SYN */
1438 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1440 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1444 /* 5: check the ACK field */
1445 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1448 /* 6: check the URG bit TODO */
1450 /* 7: process the segment text */
1451 if (vnet_buffer (b[0])->tcp.data_len)
1452 error = tcp_segment_rcv (wrk, tc, b[0]);
1454 /* 8: check the FIN bit */
1455 if (PREDICT_FALSE (tcp_is_fin (th)))
1456 tcp_rcv_fin (wrk, tc, b[0], &error);
1459 tcp_inc_err_counter (err_counters, error, 1);
1465 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1467 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1468 tcp_store_err_counters (established, err_counters);
1469 tcp_handle_postponed_dequeues (wrk);
1470 tcp_handle_disconnects (wrk);
1471 vlib_buffer_free (vm, from, frame->n_vectors);
1473 return frame->n_vectors;
1476 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1477 vlib_node_runtime_t * node,
1478 vlib_frame_t * from_frame)
1480 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1483 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1484 vlib_node_runtime_t * node,
1485 vlib_frame_t * from_frame)
1487 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1491 VLIB_REGISTER_NODE (tcp4_established_node) = {
1492 .name = "tcp4-established",
1493 /* Takes a vector of packets. */
1494 .vector_size = sizeof (u32),
1495 .n_errors = TCP_N_ERROR,
1496 .error_counters = tcp_input_error_counters,
1497 .format_trace = format_tcp_rx_trace_short,
1502 VLIB_REGISTER_NODE (tcp6_established_node) = {
1503 .name = "tcp6-established",
1504 /* Takes a vector of packets. */
1505 .vector_size = sizeof (u32),
1506 .n_errors = TCP_N_ERROR,
1507 .error_counters = tcp_input_error_counters,
1508 .format_trace = format_tcp_rx_trace_short,
1514 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1517 transport_connection_t *tmp = 0;
1524 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1527 u8 is_ip_valid = 0, val_l, val_r;
1529 if (tc->connection.is_ip4)
1531 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1533 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1534 &tc->connection.lcl_ip.ip4);
1535 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1536 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1537 &tc->connection.rmt_ip.ip4);
1538 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1539 is_ip_valid = val_l && val_r;
1543 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1545 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1546 &tc->connection.lcl_ip.ip6);
1547 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1548 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1549 &tc->connection.rmt_ip.ip6);
1550 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1551 is_ip_valid = val_l && val_r;
1554 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1555 && (tc->state == TCP_STATE_LISTEN
1556 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1560 handle = session_lookup_half_open_handle (&tc->connection);
1561 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1562 tc->c_proto, tc->c_is_ip4);
1566 if (tmp->lcl_port == hdr->dst_port
1567 && tmp->rmt_port == hdr->src_port)
1569 TCP_DBG ("half-open is valid!");
1578 * Lookup transport connection
1580 static tcp_connection_t *
1581 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1585 transport_connection_t *tconn;
1586 tcp_connection_t *tc;
1591 ip4 = vlib_buffer_get_current (b);
1592 tcp = ip4_next_header (ip4);
1593 tconn = session_lookup_connection_wt4 (fib_index,
1598 TRANSPORT_PROTO_TCP,
1599 thread_index, &is_filtered);
1600 tc = tcp_get_connection_from_transport (tconn);
1601 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1606 ip6 = vlib_buffer_get_current (b);
1607 tcp = ip6_next_header (ip6);
1608 tconn = session_lookup_connection_wt6 (fib_index,
1613 TRANSPORT_PROTO_TCP,
1614 thread_index, &is_filtered);
1615 tc = tcp_get_connection_from_transport (tconn);
1616 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1621 static tcp_connection_t *
1622 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1628 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1629 tcp_header_t *tcp = tcp_buffer_hdr (b);
1630 s = session_lookup_listener4 (fib_index,
1632 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1636 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1637 tcp_header_t *tcp = tcp_buffer_hdr (b);
1638 s = session_lookup_listener6 (fib_index,
1640 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1643 if (PREDICT_TRUE (s != 0))
1644 return tcp_get_connection_from_transport (transport_get_listener
1645 (TRANSPORT_PROTO_TCP,
1646 s->connection_index));
1652 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1653 u32 *from, u32 n_bufs)
1655 tcp_connection_t *tc = 0;
1660 for (i = 0; i < n_bufs; i++)
1662 b = vlib_get_buffer (vm, from[i]);
1663 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1666 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1667 t = vlib_add_trace (vm, node, b, sizeof (*t));
1668 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1673 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1675 vnet_main_t *vnm = vnet_get_main ();
1676 const dpo_id_t *dpo;
1677 const load_balance_t *lb;
1678 vnet_hw_interface_t *hw_if;
1679 u32 sw_if_idx, lb_idx;
1683 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1684 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1688 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1689 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1692 lb = load_balance_get (lb_idx);
1693 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1695 dpo = load_balance_get_bucket_i (lb, 0);
1697 sw_if_idx = dpo_get_urpf (dpo);
1698 if (PREDICT_FALSE (sw_if_idx == ~0))
1701 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1702 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1703 tc->cfg_flags |= TCP_CFG_F_TSO;
1707 tcp_input_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1708 vlib_buffer_t **bs, u16 *nexts, u32 n_bufs, u8 is_ip4)
1710 tcp_connection_t *tc;
1716 for (i = 0; i < n_bufs; i++)
1718 if (!(bs[i]->flags & VLIB_BUFFER_IS_TRACED))
1721 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
1722 if (nexts[i] == TCP_INPUT_NEXT_DROP || nexts[i] == TCP_INPUT_NEXT_PUNT ||
1723 nexts[i] == TCP_INPUT_NEXT_RESET)
1729 flags = vnet_buffer (bs[i])->tcp.flags;
1731 if (flags == TCP_STATE_LISTEN)
1732 tc = tcp_listener_get (vnet_buffer (bs[i])->tcp.connection_index);
1733 else if (flags == TCP_STATE_SYN_SENT)
1734 tc = tcp_half_open_connection_get (
1735 vnet_buffer (bs[i])->tcp.connection_index);
1737 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
1740 tcp = tcp_buffer_hdr (bs[i]);
1741 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
1746 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1747 vlib_frame_t *frame, int is_ip4)
1749 u32 n_left_from, *from, thread_index = vm->thread_index, errors = 0;
1750 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1751 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1753 from = vlib_frame_vector_args (frame);
1754 n_left_from = frame->n_vectors;
1756 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1757 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1759 vlib_get_buffers (vm, from, bufs, n_left_from);
1762 while (n_left_from > 0)
1764 u32 ack, seq, error = TCP_ERROR_NONE;
1765 tcp_connection_t *tc, *new_tc;
1768 tc = tcp_half_open_connection_get (
1769 vnet_buffer (b[0])->tcp.connection_index);
1770 if (PREDICT_FALSE (tc == 0))
1772 error = TCP_ERROR_INVALID_CONNECTION;
1776 /* Half-open completed or cancelled recently but the connection
1777 * was't removed yet by the owning thread */
1778 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1780 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1784 ack = vnet_buffer (b[0])->tcp.ack_number;
1785 seq = vnet_buffer (b[0])->tcp.seq_number;
1786 tcp = tcp_buffer_hdr (b[0]);
1788 /* Crude check to see if the connection handle does not match
1789 * the packet. Probably connection just switched to established */
1790 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1791 tcp->src_port != tc->c_rmt_port))
1793 error = TCP_ERROR_INVALID_CONNECTION;
1797 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1799 error = TCP_ERROR_SEGMENT_INVALID;
1803 /* SYNs consume sequence numbers */
1804 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1807 * 1. check the ACK bit
1811 * If the ACK bit is set
1812 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1813 * the RST bit is set, if so drop the segment and return)
1814 * <SEQ=SEG.ACK><CTL=RST>
1815 * and discard the segment. Return.
1816 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1820 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1823 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1824 error = TCP_ERROR_RCV_WND;
1828 /* Make sure ACK is valid */
1829 if (seq_gt (tc->snd_una, ack))
1831 error = TCP_ERROR_ACK_INVALID;
1837 * 2. check the RST bit
1842 /* If ACK is acceptable, signal client that peer is not
1843 * willing to accept connection and drop connection*/
1845 tcp_rcv_rst (wrk, tc);
1846 error = TCP_ERROR_RST_RCVD;
1851 * 3. check the security and precedence (skipped)
1855 * 4. check the SYN bit
1858 /* No SYN flag. Drop. */
1861 error = TCP_ERROR_SEGMENT_INVALID;
1866 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1868 error = TCP_ERROR_OPTIONS;
1872 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1873 * current thread pool. */
1874 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1875 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1877 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1879 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1881 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1882 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1885 if (tcp_opts_wscale (&new_tc->rcv_opts))
1886 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1888 new_tc->rcv_wscale = 0;
1890 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1891 << new_tc->snd_wscale;
1892 new_tc->snd_wl1 = seq;
1893 new_tc->snd_wl2 = ack;
1895 tcp_connection_init_vars (new_tc);
1897 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1898 if (PREDICT_TRUE (tcp_ack (tcp)))
1900 /* Our SYN is ACKed: we have iss < ack = snd_una */
1902 /* TODO Dequeue acknowledged segments if we support Fast Open */
1903 new_tc->snd_una = ack;
1904 new_tc->state = TCP_STATE_ESTABLISHED;
1906 /* Make sure las is initialized for the wnd computation */
1907 new_tc->rcv_las = new_tc->rcv_nxt;
1909 /* Notify app that we have connection. If session layer can't
1910 * allocate session send reset */
1911 if (session_stream_connect_notify (&new_tc->connection,
1914 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1915 tcp_connection_cleanup (new_tc);
1916 error = TCP_ERROR_CREATE_SESSION_FAIL;
1920 transport_fifos_init_ooo (&new_tc->connection);
1921 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1922 /* Update rtt with the syn-ack sample */
1923 tcp_estimate_initial_rtt (new_tc);
1924 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1925 error = TCP_ERROR_SYN_ACKS_RCVD;
1927 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1930 new_tc->state = TCP_STATE_SYN_RCVD;
1932 /* Notify app that we have connection */
1933 if (session_stream_connect_notify (&new_tc->connection,
1936 tcp_connection_cleanup (new_tc);
1937 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1938 TCP_EVT (TCP_EVT_RST_SENT, tc);
1939 error = TCP_ERROR_CREATE_SESSION_FAIL;
1943 transport_fifos_init_ooo (&new_tc->connection);
1944 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1946 tcp_init_snd_vars (new_tc);
1947 tcp_send_synack (new_tc);
1948 error = TCP_ERROR_SYNS_RCVD;
1952 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
1953 tcp_check_tx_offload (new_tc, is_ip4);
1955 /* Read data, if any */
1956 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
1958 clib_warning ("rcvd data in syn-sent");
1959 error = tcp_segment_rcv (wrk, new_tc, b[0]);
1960 if (error == TCP_ERROR_ACK_OK)
1961 error = TCP_ERROR_SYN_ACKS_RCVD;
1965 /* Send ack now instead of programming it because connection was
1966 * just established and it's not optional. */
1967 tcp_send_ack (new_tc);
1972 /* If this is not the owning thread, wait for syn retransmit to
1973 * expire and cleanup then */
1974 if (tcp_half_open_connection_cleanup (tc))
1975 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
1981 tcp_inc_counter (syn_sent, error, 1);
1985 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
1986 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
1987 vlib_buffer_free (vm, from, frame->n_vectors);
1988 tcp_handle_disconnects (wrk);
1990 return frame->n_vectors;
1993 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
1994 vlib_node_runtime_t * node,
1995 vlib_frame_t * from_frame)
1997 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2000 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2001 vlib_node_runtime_t * node,
2002 vlib_frame_t * from_frame)
2004 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2008 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2010 .name = "tcp4-syn-sent",
2011 /* Takes a vector of packets. */
2012 .vector_size = sizeof (u32),
2013 .n_errors = TCP_N_ERROR,
2014 .error_counters = tcp_input_error_counters,
2015 .format_trace = format_tcp_rx_trace_short,
2020 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2022 .name = "tcp6-syn-sent",
2023 /* Takes a vector of packets. */
2024 .vector_size = sizeof (u32),
2025 .n_errors = TCP_N_ERROR,
2026 .error_counters = tcp_input_error_counters,
2027 .format_trace = format_tcp_rx_trace_short,
2032 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2033 u32 *from, u32 n_bufs)
2035 u32 thread_index = vm->thread_index;
2036 tcp_connection_t *tc = 0;
2041 for (i = 0; i < n_bufs; i++)
2043 b = vlib_get_buffer (vm, from[i]);
2044 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2046 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2048 t = vlib_add_trace (vm, node, b, sizeof (*t));
2049 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2054 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2055 * as per RFC793 p. 64
2058 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2059 vlib_frame_t *frame, int is_ip4)
2061 u32 thread_index = vm->thread_index, errors, n_left_from, *from, max_deq;
2062 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2063 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2065 from = vlib_frame_vector_args (frame);
2066 n_left_from = frame->n_vectors;
2068 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2069 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2071 vlib_get_buffers (vm, from, bufs, n_left_from);
2074 while (n_left_from > 0)
2076 u32 error = TCP_ERROR_NONE;
2077 tcp_header_t *tcp = 0;
2078 tcp_connection_t *tc;
2081 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2083 if (PREDICT_FALSE (tc == 0))
2085 error = TCP_ERROR_INVALID_CONNECTION;
2089 tcp = tcp_buffer_hdr (b[0]);
2090 is_fin = tcp_is_fin (tcp);
2094 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2096 tcp_connection_t *tmp;
2097 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2099 if (tmp->state != tc->state)
2101 if (tc->state != TCP_STATE_CLOSED)
2102 clib_warning ("state changed");
2109 * Special treatment for CLOSED
2111 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2113 error = TCP_ERROR_CONNECTION_CLOSED;
2118 * For all other states (except LISTEN)
2121 /* 1-4: check SEQ, RST, SYN */
2122 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2125 /* 5: check the ACK field */
2128 case TCP_STATE_SYN_RCVD:
2130 /* Make sure the segment is exactly right */
2131 if (tc->rcv_nxt != vnet_buffer (b[0])->tcp.seq_number || is_fin)
2133 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2134 error = TCP_ERROR_SEGMENT_INVALID;
2139 * If the segment acknowledgment is not acceptable, form a
2141 * <SEQ=SEG.ACK><CTL=RST>
2144 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2146 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2147 error = TCP_ERROR_SEGMENT_INVALID;
2151 /* Update rtt and rto */
2152 tcp_estimate_initial_rtt (tc);
2153 tcp_connection_tx_pacer_update (tc);
2155 /* Switch state to ESTABLISHED */
2156 tc->state = TCP_STATE_ESTABLISHED;
2157 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2159 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2160 tcp_check_tx_offload (tc, is_ip4);
2162 /* Initialize session variables */
2163 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2164 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2165 << tc->rcv_opts.wscale;
2166 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2167 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2169 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2170 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2171 if (session_stream_accept_notify (&tc->connection))
2173 error = TCP_ERROR_MSG_QUEUE_FULL;
2174 tcp_send_reset (tc);
2175 session_transport_delete_notify (&tc->connection);
2176 tcp_connection_cleanup (tc);
2179 error = TCP_ERROR_ACK_OK;
2181 case TCP_STATE_ESTABLISHED:
2182 /* We can get packets in established state here because they
2183 * were enqueued before state change */
2184 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2188 case TCP_STATE_FIN_WAIT_1:
2189 /* In addition to the processing for the ESTABLISHED state, if
2190 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2191 * continue processing in that state. */
2192 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2195 /* Still have to send the FIN */
2196 if (tc->flags & TCP_CONN_FINPNDG)
2198 /* TX fifo finally drained */
2199 max_deq = transport_max_tx_dequeue (&tc->connection);
2200 if (max_deq <= tc->burst_acked)
2202 /* If a fin was received and data was acked extend wait */
2203 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2204 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2205 tcp_cfg.closewait_time);
2207 /* If FIN is ACKed */
2208 else if (tc->snd_una == tc->snd_nxt)
2210 /* Stop all retransmit timers because we have nothing more
2212 tcp_connection_timers_reset (tc);
2214 /* We already have a FIN but didn't transition to CLOSING
2215 * because of outstanding tx data. Close the connection. */
2216 if (tc->flags & TCP_CONN_FINRCVD)
2218 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2219 session_transport_closed_notify (&tc->connection);
2220 tcp_program_cleanup (wrk, tc);
2224 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2225 /* Enable waitclose because we're willing to wait for peer's
2226 * FIN but not indefinitely. */
2227 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2228 tcp_cfg.finwait2_time);
2230 /* Don't try to deq the FIN acked */
2231 if (tc->burst_acked > 1)
2232 session_tx_fifo_dequeue_drop (&tc->connection,
2233 tc->burst_acked - 1);
2234 tc->burst_acked = 0;
2237 case TCP_STATE_FIN_WAIT_2:
2238 /* In addition to the processing for the ESTABLISHED state, if
2239 * the retransmission queue is empty, the user's CLOSE can be
2240 * acknowledged ("ok") but do not delete the TCB. */
2241 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2243 tc->burst_acked = 0;
2245 case TCP_STATE_CLOSE_WAIT:
2246 /* Do the same processing as for the ESTABLISHED state. */
2247 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2250 if (!(tc->flags & TCP_CONN_FINPNDG))
2253 /* Still have outstanding tx data */
2254 max_deq = transport_max_tx_dequeue (&tc->connection);
2255 if (max_deq > tc->burst_acked)
2259 tcp_connection_timers_reset (tc);
2260 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2261 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2262 tcp_cfg.lastack_time);
2264 case TCP_STATE_CLOSING:
2265 /* In addition to the processing for the ESTABLISHED state, if
2266 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2267 * otherwise ignore the segment. */
2268 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2271 if (tc->snd_una != tc->snd_nxt)
2274 tcp_connection_timers_reset (tc);
2275 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2276 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2277 tcp_cfg.timewait_time);
2278 session_transport_closed_notify (&tc->connection);
2282 case TCP_STATE_LAST_ACK:
2283 /* The only thing that [should] arrive in this state is an
2284 * acknowledgment of our FIN. If our FIN is now acknowledged,
2285 * delete the TCB, enter the CLOSED state, and return. */
2287 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2290 /* Apparently our ACK for the peer's FIN was lost */
2291 if (is_fin && tc->snd_una != tc->snd_nxt)
2297 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2298 session_transport_closed_notify (&tc->connection);
2300 /* Don't free the connection from the data path since
2301 * we can't ensure that we have no packets already enqueued
2302 * to output. Rely instead on the waitclose timer */
2303 tcp_connection_timers_reset (tc);
2304 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2309 case TCP_STATE_TIME_WAIT:
2310 /* The only thing that can arrive in this state is a
2311 * retransmission of the remote FIN. Acknowledge it, and restart
2312 * the 2 MSL timeout. */
2314 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2320 tcp_program_ack (tc);
2321 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2322 tcp_cfg.timewait_time);
2330 /* 6: check the URG bit TODO */
2332 /* 7: process the segment text */
2335 case TCP_STATE_ESTABLISHED:
2336 case TCP_STATE_FIN_WAIT_1:
2337 case TCP_STATE_FIN_WAIT_2:
2338 if (vnet_buffer (b[0])->tcp.data_len)
2339 error = tcp_segment_rcv (wrk, tc, b[0]);
2340 /* Don't accept out of order fins lower */
2341 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2344 case TCP_STATE_CLOSE_WAIT:
2345 case TCP_STATE_CLOSING:
2346 case TCP_STATE_LAST_ACK:
2347 case TCP_STATE_TIME_WAIT:
2348 /* This should not occur, since a FIN has been received from the
2349 * remote side. Ignore the segment text. */
2353 /* 8: check the FIN bit */
2357 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2361 case TCP_STATE_ESTABLISHED:
2362 /* Account for the FIN and send ack */
2364 tcp_program_ack (tc);
2365 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2366 tcp_program_disconnect (wrk, tc);
2367 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2368 tcp_cfg.closewait_time);
2370 case TCP_STATE_SYN_RCVD:
2371 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2372 * notified yet, set a cleanup timer instead of relying on
2373 * disconnect notify and the implicit close call. */
2374 tcp_connection_timers_reset (tc);
2377 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2378 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2379 tcp_cfg.lastack_time);
2381 case TCP_STATE_CLOSE_WAIT:
2382 case TCP_STATE_CLOSING:
2383 case TCP_STATE_LAST_ACK:
2386 case TCP_STATE_FIN_WAIT_1:
2389 if (tc->flags & TCP_CONN_FINPNDG)
2391 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2392 * sending it. Since we already received a fin, do not wait
2394 tc->flags |= TCP_CONN_FINRCVD;
2395 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2396 tcp_cfg.closewait_time);
2400 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2401 tcp_program_ack (tc);
2402 /* Wait for ACK for our FIN but not forever */
2403 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2404 tcp_cfg.closing_time);
2407 case TCP_STATE_FIN_WAIT_2:
2408 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2410 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2411 tcp_connection_timers_reset (tc);
2412 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2413 tcp_cfg.timewait_time);
2414 tcp_program_ack (tc);
2415 session_transport_closed_notify (&tc->connection);
2417 case TCP_STATE_TIME_WAIT:
2418 /* Remain in the TIME-WAIT state. Restart the time-wait
2421 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2422 tcp_cfg.timewait_time);
2425 error = TCP_ERROR_FIN_RCVD;
2431 tcp_inc_counter (rcv_process, error, 1);
2434 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2436 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2437 tcp_handle_postponed_dequeues (wrk);
2438 tcp_handle_disconnects (wrk);
2439 vlib_buffer_free (vm, from, frame->n_vectors);
2441 return frame->n_vectors;
2444 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2445 vlib_node_runtime_t * node,
2446 vlib_frame_t * from_frame)
2448 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2451 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2452 vlib_node_runtime_t * node,
2453 vlib_frame_t * from_frame)
2455 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2459 VLIB_REGISTER_NODE (tcp4_rcv_process_node) = {
2460 .name = "tcp4-rcv-process",
2461 /* Takes a vector of packets. */
2462 .vector_size = sizeof (u32),
2463 .n_errors = TCP_N_ERROR,
2464 .error_counters = tcp_input_error_counters,
2465 .format_trace = format_tcp_rx_trace_short,
2470 VLIB_REGISTER_NODE (tcp6_rcv_process_node) = {
2471 .name = "tcp6-rcv-process",
2472 /* Takes a vector of packets. */
2473 .vector_size = sizeof (u32),
2474 .n_errors = TCP_N_ERROR,
2475 .error_counters = tcp_input_error_counters,
2476 .format_trace = format_tcp_rx_trace_short,
2481 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2482 u32 *to_next, u32 n_bufs)
2484 tcp_connection_t *tc = 0;
2489 for (i = 0; i < n_bufs; i++)
2491 b = vlib_get_buffer (vm, to_next[i]);
2492 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2494 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2495 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2496 t = vlib_add_trace (vm, node, b, sizeof (*t));
2497 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2502 * SYN received in TIME-WAIT state.
2505 * "When a connection is [...] on TIME-WAIT state [...]
2506 * [a TCP] MAY accept a new SYN from the remote TCP to
2507 * reopen the connection directly, if it:
2509 * (1) assigns its initial sequence number for the new
2510 * connection to be larger than the largest sequence
2511 * number it used on the previous connection incarnation,
2514 * (2) returns to TIME-WAIT state if the SYN turns out
2515 * to be an old duplicate".
2517 * The function returns true if the syn can be accepted during
2518 * connection time-wait (port reuse). In this case the function
2519 * also calculates what the iss should be for the new connection.
2522 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2524 int paws_reject = tcp_segment_check_paws (tc);
2528 /* Check that the SYN arrived out of window. We accept it */
2530 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2531 (tcp_opts_tstamp (&tc->rcv_opts) &&
2532 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2534 /* Set the iss of the new connection to be the largest sequence number
2535 * the old peer would have accepted and add some random number
2537 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2538 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2548 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2549 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2550 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2551 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2557 * LISTEN state processing as per RFC 793 p. 65
2560 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2561 vlib_frame_t *frame, int is_ip4)
2563 u32 n_left_from, *from, n_syns = 0;
2564 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2565 u32 thread_index = vm->thread_index;
2568 from = vlib_frame_vector_args (frame);
2569 n_left_from = frame->n_vectors;
2571 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2572 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2574 vlib_get_buffers (vm, from, bufs, n_left_from);
2577 while (n_left_from > 0)
2579 tcp_connection_t *lc, *child;
2581 /* Flags initialized with connection state after lookup */
2582 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2584 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2586 /* Probably we are in time-wait or closed state */
2589 tcp_connection_t *tc;
2590 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2592 if (tc->state != TCP_STATE_TIME_WAIT)
2594 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2598 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2600 /* This SYN can't be accepted */
2601 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2605 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2606 /* clean up the old session */
2607 tcp_connection_del (tc);
2608 /* listener was cleaned up */
2611 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
2616 /* Make sure connection wasn't just created */
2618 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2619 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2621 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2625 /* Create child session. For syn-flood protection use filter */
2627 /* 1. first check for an RST: handled by input dispatch */
2629 /* 2. second check for an ACK: handled by input dispatch */
2631 /* 3. check for a SYN (did that already) */
2633 /* Create child session and send SYN-ACK */
2634 child = tcp_connection_alloc (thread_index);
2636 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2638 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
2639 tcp_connection_free (child);
2643 tcp_init_w_buffer (child, b[0], is_ip4);
2645 child->state = TCP_STATE_SYN_RCVD;
2646 child->c_fib_index = lc->c_fib_index;
2647 child->cc_algo = lc->cc_algo;
2649 /* In the regular case, the tw_iss will be zero, but
2650 * in the special case of syn arriving in time_wait state, the value
2651 * will be set according to rfc 1122
2653 child->iss = tw_iss;
2654 tcp_connection_init_vars (child);
2655 child->rto = TCP_RTO_MIN;
2658 * This initializes elog track, must be done before synack.
2659 * We also do it before possible tcp_connection_cleanup() as it
2660 * generates TCP_EVT_DELETE event.
2662 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2664 if (session_stream_accept (&child->connection, lc->c_s_index,
2665 lc->c_thread_index, 0 /* notify */ ))
2667 tcp_connection_cleanup (child);
2668 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
2672 transport_fifos_init_ooo (&child->connection);
2673 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2675 tcp_send_synack (child);
2683 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2684 vlib_buffer_free (vm, from, frame->n_vectors);
2686 return frame->n_vectors;
2689 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2690 vlib_frame_t * from_frame)
2692 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2695 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2696 vlib_frame_t * from_frame)
2698 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2702 VLIB_REGISTER_NODE (tcp4_listen_node) = {
2703 .name = "tcp4-listen",
2704 /* Takes a vector of packets. */
2705 .vector_size = sizeof (u32),
2706 .n_errors = TCP_N_ERROR,
2707 .error_counters = tcp_input_error_counters,
2708 .format_trace = format_tcp_rx_trace_short,
2713 VLIB_REGISTER_NODE (tcp6_listen_node) = {
2714 .name = "tcp6-listen",
2715 /* Takes a vector of packets. */
2716 .vector_size = sizeof (u32),
2717 .n_errors = TCP_N_ERROR,
2718 .error_counters = tcp_input_error_counters,
2719 .format_trace = format_tcp_rx_trace_short,
2724 tcp46_drop_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2725 vlib_frame_t *frame, int is_ip4)
2727 u32 *from = vlib_frame_vector_args (frame);
2729 /* Error counters must be incremented by previous nodes */
2730 vlib_buffer_free (vm, from, frame->n_vectors);
2732 return frame->n_vectors;
2735 VLIB_NODE_FN (tcp4_drop_node)
2736 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2738 return tcp46_drop_inline (vm, node, from_frame, 1 /* is_ip4 */);
2741 VLIB_NODE_FN (tcp6_drop_node)
2742 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2744 return tcp46_drop_inline (vm, node, from_frame, 0 /* is_ip4 */);
2747 VLIB_REGISTER_NODE (tcp4_drop_node) = {
2748 .name = "tcp4-drop",
2749 .vector_size = sizeof (u32),
2750 .n_errors = TCP_N_ERROR,
2751 .error_counters = tcp_input_error_counters,
2754 VLIB_REGISTER_NODE (tcp6_drop_node) = {
2755 .name = "tcp6-drop",
2756 .vector_size = sizeof (u32),
2757 .n_errors = TCP_N_ERROR,
2758 .error_counters = tcp_input_error_counters,
2761 #define foreach_tcp4_input_next \
2762 _ (DROP, "tcp4-drop") \
2763 _ (LISTEN, "tcp4-listen") \
2764 _ (RCV_PROCESS, "tcp4-rcv-process") \
2765 _ (SYN_SENT, "tcp4-syn-sent") \
2766 _ (ESTABLISHED, "tcp4-established") \
2767 _ (RESET, "tcp4-reset") \
2768 _ (PUNT, "ip4-punt")
2770 #define foreach_tcp6_input_next \
2771 _ (DROP, "tcp6-drop") \
2772 _ (LISTEN, "tcp6-listen") \
2773 _ (RCV_PROCESS, "tcp6-rcv-process") \
2774 _ (SYN_SENT, "tcp6-syn-sent") \
2775 _ (ESTABLISHED, "tcp6-established") \
2776 _ (RESET, "tcp6-reset") \
2777 _ (PUNT, "ip6-punt")
2779 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2782 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2784 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2786 *next = TCP_INPUT_NEXT_DROP;
2788 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2790 *next = TCP_INPUT_NEXT_PUNT;
2791 *error = TCP_ERROR_PUNT;
2795 *next = TCP_INPUT_NEXT_RESET;
2796 *error = TCP_ERROR_NO_LISTENER;
2801 tcp_input_dispatch_buffer (tcp_main_t *tm, tcp_connection_t *tc,
2802 vlib_buffer_t *b, u16 *next, u16 *err_counters)
2808 tcp = tcp_buffer_hdr (b);
2809 flags = tcp->flags & filter_flags;
2810 *next = tm->dispatch_table[tc->state][flags].next;
2811 error = tm->dispatch_table[tc->state][flags].error;
2814 /* Track connection state when packet was received. It is required
2815 * for @ref tcp46_listen_inline to detect whether we reached
2816 * the node as a result of a SYN packet received while in time-wait
2817 * state. In this case the connection_index in vnet buffer will point
2818 * to the existing tcp connection and not the listener
2820 vnet_buffer (b)->tcp.flags = tc->state;
2822 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2824 tcp_inc_err_counter (err_counters, error, 1);
2825 if (error == TCP_ERROR_DISPATCH)
2826 clib_warning ("tcp conn %u disp error state %U flags %U",
2827 tc->c_c_index, format_tcp_state, tc->state,
2828 format_tcp_flags, (int) flags);
2833 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2834 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2836 u32 n_left_from, *from, thread_index = vm->thread_index;
2837 tcp_main_t *tm = vnet_get_tcp_main ();
2838 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2839 u16 nexts[VLIB_FRAME_SIZE], *next;
2840 u16 err_counters[TCP_N_ERROR] = { 0 };
2842 tcp_update_time_now (tcp_get_worker (thread_index));
2844 from = vlib_frame_vector_args (frame);
2845 n_left_from = frame->n_vectors;
2846 vlib_get_buffers (vm, from, bufs, n_left_from);
2851 while (n_left_from >= 4)
2853 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2854 tcp_connection_t *tc0, *tc1;
2857 vlib_prefetch_buffer_header (b[2], STORE);
2858 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2860 vlib_prefetch_buffer_header (b[3], STORE);
2861 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2864 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2866 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2868 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2871 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2873 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2874 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2876 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2877 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2879 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2880 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], err_counters);
2884 if (PREDICT_TRUE (tc0 != 0))
2886 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2887 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2888 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0],
2893 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2894 tcp_inc_err_counter (err_counters, error0, 1);
2897 if (PREDICT_TRUE (tc1 != 0))
2899 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2900 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2901 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1],
2906 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2907 tcp_inc_err_counter (err_counters, error1, 1);
2915 while (n_left_from > 0)
2917 tcp_connection_t *tc0;
2918 u32 error0 = TCP_ERROR_NO_LISTENER;
2920 if (n_left_from > 1)
2922 vlib_prefetch_buffer_header (b[1], STORE);
2923 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2926 next[0] = TCP_INPUT_NEXT_DROP;
2927 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2929 if (PREDICT_TRUE (tc0 != 0))
2931 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2932 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2933 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2937 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2938 tcp_inc_err_counter (err_counters, error0, 1);
2946 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2947 tcp_input_trace_frame (vm, node, bufs, nexts, frame->n_vectors, is_ip4);
2949 tcp_store_err_counters (input, err_counters);
2950 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2951 return frame->n_vectors;
2954 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2955 vlib_node_runtime_t * node,
2956 vlib_frame_t * from_frame)
2958 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2959 1 /* is_nolookup */ );
2962 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2963 vlib_node_runtime_t * node,
2964 vlib_frame_t * from_frame)
2966 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2967 1 /* is_nolookup */ );
2971 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2973 .name = "tcp4-input-nolookup",
2974 /* Takes a vector of packets. */
2975 .vector_size = sizeof (u32),
2976 .n_errors = TCP_N_ERROR,
2977 .error_counters = tcp_input_error_counters,
2978 .n_next_nodes = TCP_INPUT_N_NEXT,
2981 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2982 foreach_tcp4_input_next
2985 .format_buffer = format_tcp_header,
2986 .format_trace = format_tcp_rx_trace,
2991 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2993 .name = "tcp6-input-nolookup",
2994 /* Takes a vector of packets. */
2995 .vector_size = sizeof (u32),
2996 .n_errors = TCP_N_ERROR,
2997 .error_counters = tcp_input_error_counters,
2998 .n_next_nodes = TCP_INPUT_N_NEXT,
3001 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3002 foreach_tcp6_input_next
3005 .format_buffer = format_tcp_header,
3006 .format_trace = format_tcp_rx_trace,
3010 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3011 vlib_frame_t * from_frame)
3013 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3014 0 /* is_nolookup */ );
3017 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3018 vlib_frame_t * from_frame)
3020 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3021 0 /* is_nolookup */ );
3025 VLIB_REGISTER_NODE (tcp4_input_node) =
3027 .name = "tcp4-input",
3028 /* Takes a vector of packets. */
3029 .vector_size = sizeof (u32),
3030 .n_errors = TCP_N_ERROR,
3031 .error_counters = tcp_input_error_counters,
3032 .n_next_nodes = TCP_INPUT_N_NEXT,
3035 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3036 foreach_tcp4_input_next
3039 .format_buffer = format_tcp_header,
3040 .format_trace = format_tcp_rx_trace,
3045 VLIB_REGISTER_NODE (tcp6_input_node) =
3047 .name = "tcp6-input",
3048 /* Takes a vector of packets. */
3049 .vector_size = sizeof (u32),
3050 .n_errors = TCP_N_ERROR,
3051 .error_counters = tcp_input_error_counters,
3052 .n_next_nodes = TCP_INPUT_N_NEXT,
3055 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3056 foreach_tcp6_input_next
3059 .format_buffer = format_tcp_header,
3060 .format_trace = format_tcp_rx_trace,
3064 #ifndef CLIB_MARCH_VARIANT
3066 tcp_check_gso (tcp_connection_t *tc)
3068 tcp_check_tx_offload (tc, tc->c_is_ip4);
3072 tcp_dispatch_table_init (tcp_main_t * tm)
3075 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3076 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3078 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3079 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3082 #define _(t,f,n,e) \
3084 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3085 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3088 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3089 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3090 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3091 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3092 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3093 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3094 TCP_ERROR_ACK_INVALID);
3095 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3096 TCP_ERROR_SEGMENT_INVALID);
3097 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3098 TCP_ERROR_SEGMENT_INVALID);
3099 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3100 TCP_ERROR_INVALID_CONNECTION);
3101 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3102 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3103 TCP_ERROR_SEGMENT_INVALID);
3104 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3105 TCP_ERROR_SEGMENT_INVALID);
3106 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3107 TCP_ERROR_SEGMENT_INVALID);
3108 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3109 TCP_ERROR_SEGMENT_INVALID);
3110 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3111 TCP_ERROR_SEGMENT_INVALID);
3112 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3113 TCP_ERROR_SEGMENT_INVALID);
3114 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3115 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3116 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3117 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3118 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3119 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3121 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3122 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3124 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3126 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3127 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3128 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3129 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3131 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3133 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3134 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3135 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3137 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3138 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3139 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3140 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3141 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3142 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3143 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3144 /* SYN-ACK for a SYN */
3145 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3147 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3148 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3149 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3151 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3152 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3154 /* ACK for for established connection -> tcp-established. */
3155 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3156 /* FIN for for established connection -> tcp-established. */
3157 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3158 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3160 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3162 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3163 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3164 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3166 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3167 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3168 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3169 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3170 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3171 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3172 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3173 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3175 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3176 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3178 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3180 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3181 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3182 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3183 /* ACK or FIN-ACK to our FIN */
3184 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3185 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3187 /* FIN in reply to our FIN from the other side */
3188 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3189 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3190 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3192 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3193 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3194 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3195 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3196 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3197 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3198 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3200 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3201 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3202 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3203 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3205 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3207 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3208 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3209 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3210 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3212 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3213 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3214 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3215 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3217 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3219 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3220 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3221 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3227 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3229 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3230 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3231 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3233 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3234 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3235 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3236 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3237 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3238 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3239 /* FIN confirming that the peer (app) has closed */
3240 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3241 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3242 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3244 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3245 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3247 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3248 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3249 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3251 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3252 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3254 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3255 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3256 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3257 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3258 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3260 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3262 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3263 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3264 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3266 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3267 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3268 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3269 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3270 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3271 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3272 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3273 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3275 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3276 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3278 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3280 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3281 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3282 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3283 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3284 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3286 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3287 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3289 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3290 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3291 * incoming segment not containing a RST causes a RST to be sent in
3293 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3294 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3295 TCP_ERROR_CONNECTION_CLOSED);
3296 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3297 _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3298 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3299 TCP_ERROR_CONNECTION_CLOSED);
3303 static clib_error_t *
3304 tcp_input_init (vlib_main_t * vm)
3306 clib_error_t *error = 0;
3307 tcp_main_t *tm = vnet_get_tcp_main ();
3309 if ((error = vlib_call_init_function (vm, tcp_init)))
3312 /* Initialize dispatch table. */
3313 tcp_dispatch_table_init (tm);
3318 VLIB_INIT_FUNCTION (tcp_input_init);
3320 #endif /* CLIB_MARCH_VARIANT */
3323 * fd.io coding-style-patch-verification: ON
3326 * eval: (c-set-style "gnu")