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 *error = TCP_ERROR_ACK_INVALID;
369 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
370 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
371 *error = TCP_ERROR_ACK_OK;
376 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
378 * Note that although in the original article srtt and rttvar are scaled
379 * to minimize round-off errors, here we don't. Instead, we rely on
380 * better precision time measurements.
382 * A known limitation of the algorithm is that a drop in rtt results in a
383 * rttvar increase and bigger RTO.
385 * mrtt must be provided in @ref TCP_TICK multiples, i.e., in us. Note that
386 * timestamps are measured as ms ticks so they must be converted before
387 * calling this function.
390 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
394 err = mrtt - tc->srtt;
395 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
396 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
397 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
401 tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
403 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
407 * Update rtt estimate
409 * We have potentially three sources of rtt measurements:
411 * TSOPT difference between current and echoed timestamp. It has ms
412 * precision and can be computed per ack
413 * ACK timing one sequence number is tracked per rtt with us (micro second)
415 * rate sample if enabled, all outstanding bytes are tracked with us
416 * precision. Every ack and sack are a rtt sample
418 * Middle boxes are known to fiddle with TCP options so we give higher
419 * priority to ACK timing.
421 * For now, rate sample rtts are only used under congestion.
424 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
428 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
429 * RTT because they're ambiguous. */
430 if (tcp_in_cong_recovery (tc))
432 /* Accept rtt estimates for samples that have not been retransmitted */
433 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
434 || (rs->flags & TCP_BTS_IS_RXT))
437 tcp_estimate_rtt_us (tc, rs->rtt_time);
438 mrtt = rs->rtt_time * THZ;
442 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
444 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
445 tcp_estimate_rtt_us (tc, sample);
446 mrtt = clib_max ((u32) (sample * THZ), 1);
447 /* Allow measuring of a new RTT */
450 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
451 * snd_una, i.e., the left side of the send window:
452 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
453 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
455 mrtt = clib_max (tcp_tstamp (tc) - tc->rcv_opts.tsecr, 1);
456 mrtt *= TCP_TSTP_TO_HZ;
461 /* Ignore dubious measurements */
462 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
465 tcp_estimate_rtt (tc, mrtt);
469 /* If we got here something must've been ACKed so make sure boff is 0,
470 * even if mrtt is not valid since we update the rto lower */
478 tcp_estimate_initial_rtt (tcp_connection_t * tc)
480 u8 thread_index = vlib_num_workers ()? 1 : 0;
485 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
486 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
487 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
492 mrtt = tcp_tstamp (tc) - tc->rcv_opts.tsecr;
493 mrtt = clib_max (mrtt, 1) * TCP_TSTP_TO_HZ;
494 /* Due to retransmits we don't know the initial mrtt */
495 if (tc->rto_boff && mrtt > 1 * THZ)
497 tc->mrtt_us = (f64) mrtt *TCP_TICK;
500 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
502 /* First measurement as per RFC 6298 */
504 tc->rttvar = mrtt >> 1;
510 * Dequeue bytes for connections that have received acks in last burst
513 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
515 u32 thread_index = wrk->vm->thread_index;
516 u32 *pending_deq_acked;
517 tcp_connection_t *tc;
520 if (!vec_len (wrk->pending_deq_acked))
523 pending_deq_acked = wrk->pending_deq_acked;
524 for (i = 0; i < vec_len (pending_deq_acked); i++)
526 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
527 tc->flags &= ~TCP_CONN_DEQ_PENDING;
529 if (PREDICT_FALSE (!tc->burst_acked))
532 /* Dequeue the newly ACKed bytes */
533 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
534 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
536 if (tcp_is_descheduled (tc))
539 /* If everything has been acked, stop retransmit timer
540 * otherwise update. */
541 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
543 /* Update pacer based on our new cwnd estimate */
544 tcp_connection_tx_pacer_update (tc);
548 vec_set_len (wrk->pending_deq_acked, 0);
552 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
554 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
556 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
557 tc->flags |= TCP_CONN_DEQ_PENDING;
559 tc->burst_acked += tc->bytes_acked;
563 * Try to update snd_wnd based on feedback received from peer.
565 * If successful, and new window is 'effectively' 0, activate persist
569 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
571 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
572 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
573 if (seq_lt (tc->snd_wl1, seq)
574 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
576 tc->snd_wnd = snd_wnd;
579 TCP_EVT (TCP_EVT_SND_WND, tc);
581 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
583 if (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
585 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
587 /* Set persist timer if we just got 0 wnd. If already set,
588 * update it because some data sent with snd_wnd < snd_mss was
590 if (tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
591 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
592 tcp_persist_timer_set (&wrk->timer_wheel, tc);
597 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
599 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
600 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
603 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
606 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
616 * Init loss recovery/fast recovery.
618 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
619 * updated in @ref tcp_cc_handle_event after fast retransmit
622 tcp_cc_init_congestion (tcp_connection_t * tc)
624 tcp_fastrecovery_on (tc);
625 tc->snd_congestion = tc->snd_nxt;
626 tc->cwnd_acc_bytes = 0;
627 tc->snd_rxt_bytes = 0;
628 tc->rxt_delivered = 0;
629 tc->prr_delivered = 0;
630 tc->prr_start = tc->snd_una;
631 tc->prev_ssthresh = tc->ssthresh;
632 tc->prev_cwnd = tc->cwnd;
634 tc->snd_rxt_ts = tcp_tstamp (tc);
635 tcp_cc_congestion (tc);
637 /* Post retransmit update cwnd to ssthresh and account for the
638 * three segments that have left the network and should've been
639 * buffered at the receiver XXX */
640 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
641 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
643 tc->fr_occurences += 1;
644 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
648 tcp_cc_congestion_undo (tcp_connection_t * tc)
650 tc->cwnd = tc->prev_cwnd;
651 tc->ssthresh = tc->prev_ssthresh;
652 tcp_cc_undo_recovery (tc);
653 ASSERT (tc->rto_boff == 0);
654 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
658 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
660 return (tcp_in_recovery (tc) && tc->rto_boff == 1
662 && tcp_opts_tstamp (&tc->rcv_opts)
663 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
667 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
669 return (tcp_cc_is_spurious_timeout_rxt (tc));
673 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
677 /* If of of the two conditions lower hold, reset dupacks because
678 * we're probably after timeout (RFC6582 heuristics).
679 * If Cumulative ack does not cover more than congestion threshold,
681 * 1) The following doesn't hold: The congestion window is greater
682 * than SMSS bytes and the difference between highest_ack
683 * and prev_highest_ack is at most 4*SMSS bytes
684 * 2) Echoed timestamp in the last non-dup ack does not equal the
687 if (seq_leq (tc->snd_una, tc->snd_congestion)
688 && ((!(tc->cwnd > tc->snd_mss
689 && tc->bytes_acked <= 4 * tc->snd_mss))
690 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
696 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
700 tcp_cc_try_recover (tcp_connection_t *tc)
702 sack_scoreboard_hole_t *hole;
705 ASSERT (tcp_in_cong_recovery (tc));
707 if (tcp_cc_is_spurious_retransmit (tc))
709 tcp_cc_congestion_undo (tc);
713 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
715 tcp_recovery_off (tc);
717 /* Previous recovery left us congested. Continue sending as part
718 * of the current recovery event with an updated snd_congestion */
719 if (tc->sack_sb.sacked_bytes && tcp_in_fastrecovery (tc))
721 tc->snd_congestion = tc->snd_nxt;
725 tc->rxt_delivered = 0;
726 tc->snd_rxt_bytes = 0;
728 tc->prr_delivered = 0;
730 tc->flags &= ~TCP_CONN_RXT_PENDING;
732 hole = scoreboard_first_hole (&tc->sack_sb);
733 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
734 scoreboard_clear (&tc->sack_sb);
736 if (tcp_in_fastrecovery (tc) && !is_spurious)
737 tcp_cc_recovered (tc);
739 tcp_fastrecovery_off (tc);
740 tcp_fastrecovery_first_off (tc);
741 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
743 ASSERT (tc->rto_boff == 0);
744 ASSERT (!tcp_in_cong_recovery (tc));
745 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
751 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
753 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
755 /* Congestion avoidance */
756 tcp_cc_rcv_ack (tc, rs);
758 /* If a cumulative ack, make sure dupacks is 0 */
763 * One function to rule them all ... and in the darkness bind them
766 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
769 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
771 /* If reneging, wait for timer based retransmits */
772 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
776 * If not in recovery, figure out if we should enter
778 if (!tcp_in_cong_recovery (tc))
783 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
784 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
786 if (tcp_should_fastrecover (tc, has_sack))
788 tcp_cc_init_congestion (tc);
791 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
793 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
794 tcp_program_retransmit (tc);
801 * Already in recovery
805 * See if we can exit and stop retransmitting
807 if (seq_geq (tc->snd_una, tc->snd_congestion))
809 /* If successfully recovered, treat ack as congestion avoidance ack
810 * and return. Otherwise, we're still congested so process feedback */
811 if (!tcp_cc_try_recover (tc))
813 tcp_cc_rcv_ack (tc, rs);
819 * Process (re)transmit feedback. Output path uses this to decide how much
820 * more data to release into the network
824 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
825 tcp_fastrecovery_first_on (tc);
827 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
828 tc->prr_delivered += rs->delivered;
834 tc->rcv_dupacks += 1;
835 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
837 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
840 tc->prr_delivered += clib_min (tc->snd_mss,
841 tc->snd_nxt - tc->snd_una);
843 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
847 /* If partial ack, assume that the first un-acked segment was lost */
848 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
849 tcp_fastrecovery_first_on (tc);
852 tcp_program_retransmit (tc);
855 * Notify cc of the event
858 if (!tc->bytes_acked)
860 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
864 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
865 * reset dupacks to 0. Also needed if in congestion recovery */
868 if (tcp_in_recovery (tc))
869 tcp_cc_rcv_ack (tc, rs);
871 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
875 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
877 if (!tcp_in_cong_recovery (tc))
880 if (tcp_opts_sack_permitted (&tc->rcv_opts))
881 tcp_rcv_sacks (tc, tc->snd_una);
885 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
886 tcp_bt_sample_delivery_rate (tc, rs);
888 tcp_cc_handle_event (tc, rs, 1);
892 * Check if duplicate ack as per RFC5681 Sec. 2
895 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
898 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
899 && seq_gt (tc->snd_nxt, tc->snd_una)
900 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
901 && (prev_snd_wnd == tc->snd_wnd));
905 * Checks if ack is a congestion control event.
908 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
909 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
911 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
912 * defined to be 'duplicate' as well */
913 *is_dack = tc->sack_sb.last_sacked_bytes
914 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
916 return (*is_dack || tcp_in_cong_recovery (tc));
920 * Process incoming ACK
923 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
924 tcp_header_t * th, u32 * error)
926 u32 prev_snd_wnd, prev_snd_una;
927 tcp_rate_sample_t rs = { 0 };
930 TCP_EVT (TCP_EVT_CC_STAT, tc);
932 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
933 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
935 tc->errors.above_ack_wnd += 1;
936 *error = TCP_ERROR_ACK_FUTURE;
937 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
941 /* If old ACK, probably it's an old dupack */
942 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
944 tc->errors.below_ack_wnd += 1;
945 *error = TCP_ERROR_ACK_OLD;
946 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
948 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
951 tcp_handle_old_ack (tc, &rs);
958 * Looks okay, process feedback
961 if (tcp_opts_sack_permitted (&tc->rcv_opts))
962 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
964 prev_snd_wnd = tc->snd_wnd;
965 prev_snd_una = tc->snd_una;
966 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
967 vnet_buffer (b)->tcp.ack_number,
968 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
969 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
970 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
971 tcp_validate_txf_size (tc, tc->bytes_acked);
973 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
974 tcp_bt_sample_delivery_rate (tc, &rs);
976 rs.delivered = tc->bytes_acked + tc->sack_sb.last_sacked_bytes -
977 tc->sack_sb.last_bytes_delivered;
979 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
981 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
983 tcp_program_dequeue (wrk, tc);
986 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
989 * Check if we have congestion event
992 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
994 tcp_cc_handle_event (tc, &rs, is_dack);
995 tc->dupacks_in += is_dack;
996 if (!tcp_in_cong_recovery (tc))
998 *error = TCP_ERROR_ACK_OK;
1001 *error = TCP_ERROR_ACK_DUP;
1002 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1008 * Update congestion control (slow start/congestion avoidance)
1010 tcp_cc_update (tc, &rs);
1011 *error = TCP_ERROR_ACK_OK;
1016 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1018 if (!tcp_disconnect_pending (tc))
1020 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1021 tcp_disconnect_pending_on (tc);
1026 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1028 u32 thread_index, *pending_disconnects, *pending_resets;
1029 tcp_connection_t *tc;
1032 if (vec_len (wrk->pending_disconnects))
1034 thread_index = wrk->vm->thread_index;
1035 pending_disconnects = wrk->pending_disconnects;
1036 for (i = 0; i < vec_len (pending_disconnects); i++)
1038 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1039 tcp_disconnect_pending_off (tc);
1040 session_transport_closing_notify (&tc->connection);
1042 vec_set_len (wrk->pending_disconnects, 0);
1045 if (vec_len (wrk->pending_resets))
1047 thread_index = wrk->vm->thread_index;
1048 pending_resets = wrk->pending_resets;
1049 for (i = 0; i < vec_len (pending_resets); i++)
1051 tc = tcp_connection_get (pending_resets[i], thread_index);
1052 tcp_disconnect_pending_off (tc);
1053 tcp_handle_rst (tc);
1055 vec_set_len (wrk->pending_resets, 0);
1060 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1063 /* Reject out-of-order fins */
1064 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1067 /* Account for the FIN and send ack */
1069 tc->flags |= TCP_CONN_FINRCVD;
1070 tcp_program_ack (tc);
1071 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1072 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1073 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1074 tcp_program_disconnect (wrk, tc);
1075 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1076 tcp_cfg.closewait_time);
1077 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1078 *error = TCP_ERROR_FIN_RCVD;
1081 /** Enqueue data for delivery to application */
1083 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1086 int written, error = TCP_ERROR_ENQUEUED;
1088 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1090 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1091 1 /* queue event */ , 1);
1093 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1095 /* Update rcv_nxt */
1096 if (PREDICT_TRUE (written == data_len))
1098 tc->rcv_nxt += written;
1099 tc->bytes_in += written;
1101 /* If more data written than expected, account for out-of-order bytes. */
1102 else if (written > data_len)
1104 tc->rcv_nxt += written;
1105 tc->bytes_in += data_len;
1106 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1108 else if (written > 0)
1110 /* We've written something but FIFO is probably full now */
1111 tc->rcv_nxt += written;
1112 tc->bytes_in += written;
1113 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1117 /* Packet made it through for ack processing */
1118 if (tc->rcv_wnd < tc->snd_mss)
1119 return TCP_ERROR_ZERO_RWND;
1121 return TCP_ERROR_FIFO_FULL;
1124 /* Update SACK list if need be */
1125 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
1127 /* Remove SACK blocks that have been delivered */
1128 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1134 /** Enqueue out-of-order data */
1136 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1142 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1145 /* Enqueue out-of-order data with relative offset */
1146 rv = session_enqueue_stream_connection (&tc->connection, b,
1147 vnet_buffer (b)->tcp.seq_number -
1148 tc->rcv_nxt, 0 /* queue event */ ,
1151 /* Nothing written */
1154 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1155 return TCP_ERROR_FIFO_FULL;
1158 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1159 tc->bytes_in += data_len;
1161 /* Update SACK list if in use */
1162 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1164 ooo_segment_t *newest;
1167 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1169 /* Get the newest segment from the fifo */
1170 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1173 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1174 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1175 start = tc->rcv_nxt + offset;
1176 end = start + ooo_segment_length (s0->rx_fifo, newest);
1177 tcp_update_sack_list (tc, start, end);
1178 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1179 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1183 return TCP_ERROR_ENQUEUED_OOO;
1187 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1189 u32 discard, first = b->current_length;
1190 vlib_main_t *vm = vlib_get_main ();
1192 /* Handle multi-buffer segments */
1193 if (n_bytes_to_drop > b->current_length)
1195 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1199 discard = clib_min (n_bytes_to_drop, b->current_length);
1200 vlib_buffer_advance (b, discard);
1201 b = vlib_get_buffer (vm, b->next_buffer);
1202 n_bytes_to_drop -= discard;
1204 while (n_bytes_to_drop);
1205 if (n_bytes_to_drop > first)
1206 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1209 vlib_buffer_advance (b, n_bytes_to_drop);
1210 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1215 * Receive buffer for connection and handle acks
1217 * It handles both in order or out-of-order data.
1220 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1223 u32 error, n_bytes_to_drop, n_data_bytes;
1225 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1226 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1227 ASSERT (n_data_bytes);
1228 tc->data_segs_in += 1;
1230 /* Make sure we don't consume trailing bytes */
1231 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1232 b->current_length = n_data_bytes;
1234 /* Handle out-of-order data */
1235 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1237 /* Old sequence numbers allowed through because they overlapped
1239 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1241 /* Completely in the past (possible retransmit). Ack
1242 * retransmissions since we may not have any data to send */
1243 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1245 tcp_program_dupack (tc);
1246 tc->errors.below_data_wnd++;
1247 error = TCP_ERROR_SEGMENT_OLD;
1251 /* Chop off the bytes in the past and see if what is left
1252 * can be enqueued in order */
1253 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1254 n_data_bytes -= n_bytes_to_drop;
1255 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1256 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1258 error = TCP_ERROR_SEGMENT_OLD;
1264 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1265 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1266 tcp_program_dupack (tc);
1267 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1268 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1269 tc->rcv_las + tc->rcv_wnd);
1275 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1276 * segments can be enqueued after fifo tail offset changes. */
1277 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1278 tcp_program_ack (tc);
1286 tcp_header_t tcp_header;
1287 tcp_connection_t tcp_connection;
1291 format_tcp_rx_trace (u8 * s, va_list * args)
1293 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1294 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1295 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1296 tcp_connection_t *tc = &t->tcp_connection;
1297 u32 indent = format_get_indent (s);
1299 if (!tc->c_lcl_port)
1300 s = format (s, "no tcp connection\n%U%U", format_white_space, indent,
1301 format_tcp_header, &t->tcp_header, 128);
1303 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1304 format_tcp_state, tc->state, format_white_space, indent,
1305 format_tcp_header, &t->tcp_header, 128);
1311 format_tcp_rx_trace_short (u8 * s, va_list * args)
1313 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1314 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1315 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1317 s = format (s, "%d -> %d (%U)",
1318 clib_net_to_host_u16 (t->tcp_header.dst_port),
1319 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1320 t->tcp_connection.state);
1326 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1327 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1331 clib_memcpy_fast (&t0->tcp_connection, tc0,
1332 sizeof (t0->tcp_connection));
1336 th0 = tcp_buffer_hdr (b0);
1338 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1342 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1343 vlib_frame_t * frame, u8 is_ip4)
1347 n_left = frame->n_vectors;
1348 from = vlib_frame_vector_args (frame);
1352 tcp_connection_t *tc0;
1359 b0 = vlib_get_buffer (vm, bi0);
1361 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1363 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1364 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1366 th0 = tcp_buffer_hdr (b0);
1367 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1376 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1377 vlib_frame_t * frame, int is_ip4)
1379 u32 thread_index = vm->thread_index, n_left_from, *from;
1380 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1381 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1382 u16 err_counters[TCP_N_ERROR] = { 0 };
1384 if (node->flags & VLIB_NODE_FLAG_TRACE)
1385 tcp_established_trace_frame (vm, node, frame, is_ip4);
1387 from = vlib_frame_vector_args (frame);
1388 n_left_from = frame->n_vectors;
1390 vlib_get_buffers (vm, from, bufs, n_left_from);
1393 while (n_left_from > 0)
1395 u32 error = TCP_ERROR_ACK_OK;
1396 tcp_connection_t *tc;
1399 if (n_left_from > 1)
1401 vlib_prefetch_buffer_header (b[1], LOAD);
1402 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1405 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1408 if (PREDICT_FALSE (tc == 0))
1410 error = TCP_ERROR_INVALID_CONNECTION;
1414 th = tcp_buffer_hdr (b[0]);
1416 /* TODO header prediction fast path */
1418 /* 1-4: check SEQ, RST, SYN */
1419 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1421 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1425 /* 5: check the ACK field */
1426 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1429 /* 6: check the URG bit TODO */
1431 /* 7: process the segment text */
1432 if (vnet_buffer (b[0])->tcp.data_len)
1433 error = tcp_segment_rcv (wrk, tc, b[0]);
1435 /* 8: check the FIN bit */
1436 if (PREDICT_FALSE (tcp_is_fin (th)))
1437 tcp_rcv_fin (wrk, tc, b[0], &error);
1440 tcp_inc_err_counter (err_counters, error, 1);
1446 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
1447 tcp_store_err_counters (established, err_counters);
1448 tcp_handle_postponed_dequeues (wrk);
1449 tcp_handle_disconnects (wrk);
1450 vlib_buffer_free (vm, from, frame->n_vectors);
1452 return frame->n_vectors;
1455 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1456 vlib_node_runtime_t * node,
1457 vlib_frame_t * from_frame)
1459 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1462 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1463 vlib_node_runtime_t * node,
1464 vlib_frame_t * from_frame)
1466 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1469 VLIB_REGISTER_NODE (tcp4_established_node) = {
1470 .name = "tcp4-established",
1471 /* Takes a vector of packets. */
1472 .vector_size = sizeof (u32),
1473 .n_errors = TCP_N_ERROR,
1474 .error_counters = tcp_input_error_counters,
1475 .format_trace = format_tcp_rx_trace_short,
1478 VLIB_REGISTER_NODE (tcp6_established_node) = {
1479 .name = "tcp6-established",
1480 /* Takes a vector of packets. */
1481 .vector_size = sizeof (u32),
1482 .n_errors = TCP_N_ERROR,
1483 .error_counters = tcp_input_error_counters,
1484 .format_trace = format_tcp_rx_trace_short,
1489 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1492 transport_connection_t *tmp = 0;
1499 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1502 u8 is_ip_valid = 0, val_l, val_r;
1504 if (tc->connection.is_ip4)
1506 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1508 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1509 &tc->connection.lcl_ip.ip4);
1510 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1511 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1512 &tc->connection.rmt_ip.ip4);
1513 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1514 is_ip_valid = val_l && val_r;
1518 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1520 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1521 &tc->connection.lcl_ip.ip6);
1522 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1523 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1524 &tc->connection.rmt_ip.ip6);
1525 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1526 is_ip_valid = val_l && val_r;
1529 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1530 && (tc->state == TCP_STATE_LISTEN
1531 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1535 handle = session_lookup_half_open_handle (&tc->connection);
1536 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1537 tc->c_proto, tc->c_is_ip4);
1541 if (tmp->lcl_port == hdr->dst_port
1542 && tmp->rmt_port == hdr->src_port)
1544 TCP_DBG ("half-open is valid!");
1553 * Lookup transport connection
1555 static tcp_connection_t *
1556 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1560 transport_connection_t *tconn;
1561 tcp_connection_t *tc;
1566 ip4 = vlib_buffer_get_current (b);
1567 tcp = ip4_next_header (ip4);
1568 tconn = session_lookup_connection_wt4 (fib_index,
1573 TRANSPORT_PROTO_TCP,
1574 thread_index, &is_filtered);
1575 tc = tcp_get_connection_from_transport (tconn);
1576 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1581 ip6 = vlib_buffer_get_current (b);
1582 tcp = ip6_next_header (ip6);
1583 tconn = session_lookup_connection_wt6 (fib_index,
1588 TRANSPORT_PROTO_TCP,
1589 thread_index, &is_filtered);
1590 tc = tcp_get_connection_from_transport (tconn);
1591 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1596 static tcp_connection_t *
1597 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1603 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1604 tcp_header_t *tcp = tcp_buffer_hdr (b);
1605 s = session_lookup_listener4 (fib_index,
1607 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1611 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1612 tcp_header_t *tcp = tcp_buffer_hdr (b);
1613 s = session_lookup_listener6 (fib_index,
1615 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1618 if (PREDICT_TRUE (s != 0))
1619 return tcp_get_connection_from_transport (transport_get_listener
1620 (TRANSPORT_PROTO_TCP,
1621 s->connection_index));
1627 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1628 u32 *from, u32 n_bufs)
1630 tcp_connection_t *tc = 0;
1635 for (i = 0; i < n_bufs; i++)
1637 b = vlib_get_buffer (vm, from[i]);
1638 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1641 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1642 t = vlib_add_trace (vm, node, b, sizeof (*t));
1643 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1648 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1650 vnet_main_t *vnm = vnet_get_main ();
1651 const dpo_id_t *dpo;
1652 const load_balance_t *lb;
1653 vnet_hw_interface_t *hw_if;
1654 u32 sw_if_idx, lb_idx;
1658 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1659 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1663 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1664 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1667 lb = load_balance_get (lb_idx);
1668 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1670 dpo = load_balance_get_bucket_i (lb, 0);
1672 sw_if_idx = dpo_get_urpf (dpo);
1673 if (PREDICT_FALSE (sw_if_idx == ~0))
1676 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1677 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1678 tc->cfg_flags |= TCP_CFG_F_TSO;
1682 tcp_input_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1683 vlib_buffer_t **bs, u16 *nexts, u32 n_bufs, u8 is_ip4)
1685 tcp_connection_t *tc;
1691 for (i = 0; i < n_bufs; i++)
1693 if (!(bs[i]->flags & VLIB_BUFFER_IS_TRACED))
1696 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
1697 if (nexts[i] == TCP_INPUT_NEXT_DROP || nexts[i] == TCP_INPUT_NEXT_PUNT ||
1698 nexts[i] == TCP_INPUT_NEXT_RESET)
1704 flags = vnet_buffer (bs[i])->tcp.flags;
1706 if (flags == TCP_STATE_LISTEN)
1707 tc = tcp_listener_get (vnet_buffer (bs[i])->tcp.connection_index);
1708 else if (flags == TCP_STATE_SYN_SENT)
1709 tc = tcp_half_open_connection_get (
1710 vnet_buffer (bs[i])->tcp.connection_index);
1712 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
1715 tcp = tcp_buffer_hdr (bs[i]);
1716 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
1721 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1722 vlib_frame_t *frame, int is_ip4)
1724 u32 n_left_from, *from, thread_index = vm->thread_index;
1725 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1726 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1728 from = vlib_frame_vector_args (frame);
1729 n_left_from = frame->n_vectors;
1731 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1732 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1734 vlib_get_buffers (vm, from, bufs, n_left_from);
1737 while (n_left_from > 0)
1739 u32 ack, seq, error = TCP_ERROR_NONE;
1740 tcp_connection_t *tc, *new_tc;
1743 tc = tcp_half_open_connection_get (
1744 vnet_buffer (b[0])->tcp.connection_index);
1745 if (PREDICT_FALSE (tc == 0))
1747 error = TCP_ERROR_INVALID_CONNECTION;
1751 /* Half-open completed or cancelled recently but the connection
1752 * was't removed yet by the owning thread */
1753 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1755 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1759 ack = vnet_buffer (b[0])->tcp.ack_number;
1760 seq = vnet_buffer (b[0])->tcp.seq_number;
1761 tcp = tcp_buffer_hdr (b[0]);
1763 /* Crude check to see if the connection handle does not match
1764 * the packet. Probably connection just switched to established */
1765 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1766 tcp->src_port != tc->c_rmt_port))
1768 error = TCP_ERROR_INVALID_CONNECTION;
1772 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1774 error = TCP_ERROR_SEGMENT_INVALID;
1778 /* SYNs consume sequence numbers */
1779 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1782 * 1. check the ACK bit
1786 * If the ACK bit is set
1787 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1788 * the RST bit is set, if so drop the segment and return)
1789 * <SEQ=SEG.ACK><CTL=RST>
1790 * and discard the segment. Return.
1791 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1795 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1798 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1799 error = TCP_ERROR_RCV_WND;
1803 /* Make sure ACK is valid */
1804 if (seq_gt (tc->snd_una, ack))
1806 error = TCP_ERROR_ACK_INVALID;
1812 * 2. check the RST bit
1817 /* If ACK is acceptable, signal client that peer is not
1818 * willing to accept connection and drop connection*/
1820 tcp_rcv_rst (wrk, tc);
1821 error = TCP_ERROR_RST_RCVD;
1826 * 3. check the security and precedence (skipped)
1830 * 4. check the SYN bit
1833 /* No SYN flag. Drop. */
1836 error = TCP_ERROR_SEGMENT_INVALID;
1841 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1843 error = TCP_ERROR_OPTIONS;
1847 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1848 * current thread pool. */
1849 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1850 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1852 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1854 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1856 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1857 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1860 if (tcp_opts_wscale (&new_tc->rcv_opts))
1861 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1863 new_tc->rcv_wscale = 0;
1865 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1866 << new_tc->snd_wscale;
1867 new_tc->snd_wl1 = seq;
1868 new_tc->snd_wl2 = ack;
1870 tcp_connection_init_vars (new_tc);
1872 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1873 if (PREDICT_TRUE (tcp_ack (tcp)))
1875 /* Our SYN is ACKed: we have iss < ack = snd_una */
1877 /* TODO Dequeue acknowledged segments if we support Fast Open */
1878 new_tc->snd_una = ack;
1879 new_tc->state = TCP_STATE_ESTABLISHED;
1881 /* Make sure las is initialized for the wnd computation */
1882 new_tc->rcv_las = new_tc->rcv_nxt;
1884 /* Notify app that we have connection. If session layer can't
1885 * allocate session send reset */
1886 if (session_stream_connect_notify (&new_tc->connection,
1889 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1890 tcp_program_cleanup (wrk, new_tc);
1891 new_tc->state = TCP_STATE_CLOSED;
1892 new_tc->c_s_index = ~0;
1893 error = TCP_ERROR_CREATE_SESSION_FAIL;
1897 transport_fifos_init_ooo (&new_tc->connection);
1898 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1899 /* Update rtt with the syn-ack sample */
1900 tcp_estimate_initial_rtt (new_tc);
1901 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1902 error = TCP_ERROR_SYN_ACKS_RCVD;
1904 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1907 new_tc->state = TCP_STATE_SYN_RCVD;
1909 /* Notify app that we have connection */
1910 if (session_stream_connect_notify (&new_tc->connection,
1913 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1914 tcp_program_cleanup (wrk, new_tc);
1915 new_tc->state = TCP_STATE_CLOSED;
1916 new_tc->c_s_index = ~0;
1917 TCP_EVT (TCP_EVT_RST_SENT, tc);
1918 error = TCP_ERROR_CREATE_SESSION_FAIL;
1922 transport_fifos_init_ooo (&new_tc->connection);
1923 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1925 tcp_init_snd_vars (new_tc);
1926 tcp_send_synack (new_tc);
1927 error = TCP_ERROR_SYNS_RCVD;
1931 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
1932 tcp_check_tx_offload (new_tc, is_ip4);
1934 /* Read data, if any */
1935 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
1937 clib_warning ("rcvd data in syn-sent");
1938 error = tcp_segment_rcv (wrk, new_tc, b[0]);
1939 if (error == TCP_ERROR_ACK_OK)
1940 error = TCP_ERROR_SYN_ACKS_RCVD;
1944 /* Send ack now instead of programming it because connection was
1945 * just established and it's not optional. */
1946 tcp_send_ack (new_tc);
1951 /* If this is not the owning thread, wait for syn retransmit to
1952 * expire and cleanup then */
1953 if (tcp_half_open_connection_cleanup (tc))
1954 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
1960 tcp_inc_counter (syn_sent, error, 1);
1963 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
1964 vlib_buffer_free (vm, from, frame->n_vectors);
1965 tcp_handle_disconnects (wrk);
1967 return frame->n_vectors;
1970 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
1971 vlib_node_runtime_t * node,
1972 vlib_frame_t * from_frame)
1974 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1977 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
1978 vlib_node_runtime_t * node,
1979 vlib_frame_t * from_frame)
1981 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1984 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
1986 .name = "tcp4-syn-sent",
1987 /* Takes a vector of packets. */
1988 .vector_size = sizeof (u32),
1989 .n_errors = TCP_N_ERROR,
1990 .error_counters = tcp_input_error_counters,
1991 .format_trace = format_tcp_rx_trace_short,
1994 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
1996 .name = "tcp6-syn-sent",
1997 /* Takes a vector of packets. */
1998 .vector_size = sizeof (u32),
1999 .n_errors = TCP_N_ERROR,
2000 .error_counters = tcp_input_error_counters,
2001 .format_trace = format_tcp_rx_trace_short,
2005 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2006 u32 *from, u32 n_bufs)
2008 u32 thread_index = vm->thread_index;
2009 tcp_connection_t *tc = 0;
2014 for (i = 0; i < n_bufs; i++)
2016 b = vlib_get_buffer (vm, from[i]);
2017 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2019 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2021 t = vlib_add_trace (vm, node, b, sizeof (*t));
2022 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2027 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2028 * as per RFC793 p. 64
2031 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2032 vlib_frame_t *frame, int is_ip4)
2034 u32 thread_index = vm->thread_index, n_left_from, *from, max_deq;
2035 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2036 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2038 from = vlib_frame_vector_args (frame);
2039 n_left_from = frame->n_vectors;
2041 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2042 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2044 vlib_get_buffers (vm, from, bufs, n_left_from);
2047 while (n_left_from > 0)
2049 u32 error = TCP_ERROR_NONE;
2050 tcp_header_t *tcp = 0;
2051 tcp_connection_t *tc;
2054 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2056 if (PREDICT_FALSE (tc == 0))
2058 error = TCP_ERROR_INVALID_CONNECTION;
2062 tcp = tcp_buffer_hdr (b[0]);
2063 is_fin = tcp_is_fin (tcp);
2067 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2069 tcp_connection_t *tmp;
2070 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2072 if (tmp->state != tc->state)
2074 if (tc->state != TCP_STATE_CLOSED)
2075 clib_warning ("state changed");
2082 * Special treatment for CLOSED
2084 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2086 error = TCP_ERROR_CONNECTION_CLOSED;
2091 * For all other states (except LISTEN)
2094 /* 1-4: check SEQ, RST, SYN */
2095 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2098 /* 5: check the ACK field */
2101 case TCP_STATE_SYN_RCVD:
2103 * If the segment acknowledgment is not acceptable, form a
2105 * <SEQ=SEG.ACK><CTL=RST>
2108 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2110 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2111 error = TCP_ERROR_SEGMENT_INVALID;
2115 /* Avoid notifying app if connection is about to be closed */
2116 if (PREDICT_FALSE (is_fin))
2119 /* Update rtt and rto */
2120 tcp_estimate_initial_rtt (tc);
2121 tcp_connection_tx_pacer_update (tc);
2123 /* Switch state to ESTABLISHED */
2124 tc->state = TCP_STATE_ESTABLISHED;
2125 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2127 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2128 tcp_check_tx_offload (tc, is_ip4);
2130 /* Initialize session variables */
2131 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2132 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2133 << tc->rcv_opts.wscale;
2134 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2135 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2137 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2138 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2139 if (session_stream_accept_notify (&tc->connection))
2141 error = TCP_ERROR_MSG_QUEUE_FULL;
2142 tcp_send_reset (tc);
2143 session_transport_delete_notify (&tc->connection);
2144 tcp_connection_cleanup (tc);
2147 error = TCP_ERROR_CONN_ACCEPTED;
2149 case TCP_STATE_ESTABLISHED:
2150 /* We can get packets in established state here because they
2151 * were enqueued before state change */
2152 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2156 case TCP_STATE_FIN_WAIT_1:
2157 /* In addition to the processing for the ESTABLISHED state, if
2158 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2159 * continue processing in that state. */
2160 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2163 /* Still have to send the FIN */
2164 if (tc->flags & TCP_CONN_FINPNDG)
2166 /* TX fifo finally drained */
2167 max_deq = transport_max_tx_dequeue (&tc->connection);
2168 if (max_deq <= tc->burst_acked)
2170 /* If a fin was received and data was acked extend wait */
2171 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2172 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2173 tcp_cfg.closewait_time);
2175 /* If FIN is ACKed */
2176 else if (tc->snd_una == tc->snd_nxt)
2178 /* Stop all retransmit timers because we have nothing more
2180 tcp_connection_timers_reset (tc);
2182 /* We already have a FIN but didn't transition to CLOSING
2183 * because of outstanding tx data. Close the connection. */
2184 if (tc->flags & TCP_CONN_FINRCVD)
2186 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2187 session_transport_closed_notify (&tc->connection);
2188 tcp_program_cleanup (wrk, tc);
2192 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2193 /* Enable waitclose because we're willing to wait for peer's
2194 * FIN but not indefinitely. */
2195 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2196 tcp_cfg.finwait2_time);
2198 /* Don't try to deq the FIN acked */
2199 if (tc->burst_acked > 1)
2200 session_tx_fifo_dequeue_drop (&tc->connection,
2201 tc->burst_acked - 1);
2202 tc->burst_acked = 0;
2205 case TCP_STATE_FIN_WAIT_2:
2206 /* In addition to the processing for the ESTABLISHED state, if
2207 * the retransmission queue is empty, the user's CLOSE can be
2208 * acknowledged ("ok") but do not delete the TCB. */
2209 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2211 tc->burst_acked = 0;
2213 case TCP_STATE_CLOSE_WAIT:
2214 /* Do the same processing as for the ESTABLISHED state. */
2215 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2218 if (!(tc->flags & TCP_CONN_FINPNDG))
2221 /* Still have outstanding tx data */
2222 max_deq = transport_max_tx_dequeue (&tc->connection);
2223 if (max_deq > tc->burst_acked)
2226 tcp_connection_timers_reset (tc);
2228 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2229 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2230 tcp_cfg.lastack_time);
2232 case TCP_STATE_CLOSING:
2233 /* In addition to the processing for the ESTABLISHED state, if
2234 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2235 * otherwise ignore the segment. */
2236 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2239 if (tc->snd_una != tc->snd_nxt)
2242 tcp_connection_timers_reset (tc);
2243 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2244 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2245 tcp_cfg.timewait_time);
2246 session_transport_closed_notify (&tc->connection);
2250 case TCP_STATE_LAST_ACK:
2251 /* The only thing that [should] arrive in this state is an
2252 * acknowledgment of our FIN. If our FIN is now acknowledged,
2253 * delete the TCB, enter the CLOSED state, and return. */
2255 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2258 /* Apparently our ACK for the peer's FIN was lost */
2259 if (is_fin && tc->snd_una != tc->snd_nxt)
2265 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2266 session_transport_closed_notify (&tc->connection);
2268 /* Don't free the connection from the data path since
2269 * we can't ensure that we have no packets already enqueued
2270 * to output. Rely instead on the waitclose timer */
2271 tcp_connection_timers_reset (tc);
2272 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2277 case TCP_STATE_TIME_WAIT:
2278 /* The only thing that can arrive in this state is a
2279 * retransmission of the remote FIN. Acknowledge it, and restart
2280 * the 2 MSL timeout. */
2282 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2288 tcp_program_ack (tc);
2289 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2290 tcp_cfg.timewait_time);
2298 /* 6: check the URG bit TODO */
2300 /* 7: process the segment text */
2303 case TCP_STATE_ESTABLISHED:
2304 case TCP_STATE_FIN_WAIT_1:
2305 case TCP_STATE_FIN_WAIT_2:
2306 if (vnet_buffer (b[0])->tcp.data_len)
2307 error = tcp_segment_rcv (wrk, tc, b[0]);
2308 /* Don't accept out of order fins lower */
2309 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2312 case TCP_STATE_CLOSE_WAIT:
2313 case TCP_STATE_CLOSING:
2314 case TCP_STATE_LAST_ACK:
2315 case TCP_STATE_TIME_WAIT:
2316 /* This should not occur, since a FIN has been received from the
2317 * remote side. Ignore the segment text. */
2321 /* 8: check the FIN bit */
2325 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2329 case TCP_STATE_ESTABLISHED:
2330 /* Account for the FIN and send ack */
2332 tcp_program_ack (tc);
2333 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2334 tcp_program_disconnect (wrk, tc);
2335 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2336 tcp_cfg.closewait_time);
2338 case TCP_STATE_SYN_RCVD:
2339 /* Send FIN-ACK and enter TIME-WAIT, as opposed to LAST-ACK,
2340 * because the app was not notified yet and we want to avoid
2341 * session state transitions to ensure cleanup does not
2342 * propagate to app. */
2343 tcp_connection_timers_reset (tc);
2346 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2347 tcp_program_cleanup (wrk, tc);
2349 case TCP_STATE_CLOSE_WAIT:
2350 case TCP_STATE_CLOSING:
2351 case TCP_STATE_LAST_ACK:
2354 case TCP_STATE_FIN_WAIT_1:
2357 if (tc->flags & TCP_CONN_FINPNDG)
2359 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2360 * sending it. Since we already received a fin, do not wait
2362 tc->flags |= TCP_CONN_FINRCVD;
2363 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2364 tcp_cfg.closewait_time);
2368 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2369 tcp_program_ack (tc);
2370 /* Wait for ACK for our FIN but not forever */
2371 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2372 tcp_cfg.closing_time);
2375 case TCP_STATE_FIN_WAIT_2:
2376 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2378 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2379 tcp_connection_timers_reset (tc);
2380 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2381 tcp_cfg.timewait_time);
2382 tcp_program_ack (tc);
2383 session_transport_closed_notify (&tc->connection);
2385 case TCP_STATE_TIME_WAIT:
2386 /* Remain in the TIME-WAIT state. Restart the time-wait
2389 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2390 tcp_cfg.timewait_time);
2393 error = TCP_ERROR_FIN_RCVD;
2399 tcp_inc_counter (rcv_process, error, 1);
2402 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2403 tcp_handle_postponed_dequeues (wrk);
2404 tcp_handle_disconnects (wrk);
2405 vlib_buffer_free (vm, from, frame->n_vectors);
2407 return frame->n_vectors;
2410 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2411 vlib_node_runtime_t * node,
2412 vlib_frame_t * from_frame)
2414 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2417 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2418 vlib_node_runtime_t * node,
2419 vlib_frame_t * from_frame)
2421 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2424 VLIB_REGISTER_NODE (tcp4_rcv_process_node) = {
2425 .name = "tcp4-rcv-process",
2426 /* Takes a vector of packets. */
2427 .vector_size = sizeof (u32),
2428 .n_errors = TCP_N_ERROR,
2429 .error_counters = tcp_input_error_counters,
2430 .format_trace = format_tcp_rx_trace_short,
2433 VLIB_REGISTER_NODE (tcp6_rcv_process_node) = {
2434 .name = "tcp6-rcv-process",
2435 /* Takes a vector of packets. */
2436 .vector_size = sizeof (u32),
2437 .n_errors = TCP_N_ERROR,
2438 .error_counters = tcp_input_error_counters,
2439 .format_trace = format_tcp_rx_trace_short,
2443 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2444 u32 *to_next, u32 n_bufs)
2446 tcp_connection_t *tc = 0;
2451 for (i = 0; i < n_bufs; i++)
2453 b = vlib_get_buffer (vm, to_next[i]);
2454 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2456 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2457 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2458 t = vlib_add_trace (vm, node, b, sizeof (*t));
2459 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2464 * SYN received in TIME-WAIT state.
2467 * "When a connection is [...] on TIME-WAIT state [...]
2468 * [a TCP] MAY accept a new SYN from the remote TCP to
2469 * reopen the connection directly, if it:
2471 * (1) assigns its initial sequence number for the new
2472 * connection to be larger than the largest sequence
2473 * number it used on the previous connection incarnation,
2476 * (2) returns to TIME-WAIT state if the SYN turns out
2477 * to be an old duplicate".
2479 * The function returns true if the syn can be accepted during
2480 * connection time-wait (port reuse). In this case the function
2481 * also calculates what the iss should be for the new connection.
2484 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2486 int paws_reject = tcp_segment_check_paws (tc);
2490 /* Check that the SYN arrived out of window. We accept it */
2492 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2493 (tcp_opts_tstamp (&tc->rcv_opts) &&
2494 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2496 /* Set the iss of the new connection to be the largest sequence number
2497 * the old peer would have accepted and add some random number
2499 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2500 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2510 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2511 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2512 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2513 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2519 * LISTEN state processing as per RFC 793 p. 65
2522 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2523 vlib_frame_t *frame, int is_ip4)
2525 u32 n_left_from, *from, n_syns = 0;
2526 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2527 u32 thread_index = vm->thread_index;
2530 from = vlib_frame_vector_args (frame);
2531 n_left_from = frame->n_vectors;
2533 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2534 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2536 vlib_get_buffers (vm, from, bufs, n_left_from);
2539 while (n_left_from > 0)
2541 tcp_connection_t *lc, *child;
2543 /* Flags initialized with connection state after lookup */
2544 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2546 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2548 /* Probably we are in time-wait or closed state */
2551 tcp_connection_t *tc;
2552 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2554 if (tc->state != TCP_STATE_TIME_WAIT)
2556 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2560 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2562 /* This SYN can't be accepted */
2563 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2567 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2568 /* clean up the old session */
2569 tcp_connection_del (tc);
2570 /* listener was cleaned up */
2573 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
2578 /* Make sure connection wasn't just created */
2580 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2581 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2583 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2587 /* Create child session. For syn-flood protection use filter */
2589 /* 1. first check for an RST: handled by input dispatch */
2591 /* 2. second check for an ACK: handled by input dispatch */
2593 /* 3. check for a SYN (did that already) */
2595 /* Create child session and send SYN-ACK */
2596 child = tcp_connection_alloc (thread_index);
2598 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2600 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
2601 tcp_connection_free (child);
2605 tcp_init_w_buffer (child, b[0], is_ip4);
2607 child->state = TCP_STATE_SYN_RCVD;
2608 child->c_fib_index = lc->c_fib_index;
2609 child->cc_algo = lc->cc_algo;
2611 /* In the regular case, the tw_iss will be zero, but
2612 * in the special case of syn arriving in time_wait state, the value
2613 * will be set according to rfc 1122
2615 child->iss = tw_iss;
2616 tcp_connection_init_vars (child);
2617 child->rto = TCP_RTO_MIN;
2620 * This initializes elog track, must be done before synack.
2621 * We also do it before possible tcp_connection_cleanup() as it
2622 * generates TCP_EVT_DELETE event.
2624 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2626 if (session_stream_accept (&child->connection, lc->c_s_index,
2627 lc->c_thread_index, 0 /* notify */ ))
2629 tcp_connection_cleanup (child);
2630 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
2634 transport_fifos_init_ooo (&child->connection);
2635 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2637 tcp_send_synack (child);
2645 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2646 vlib_buffer_free (vm, from, frame->n_vectors);
2648 return frame->n_vectors;
2651 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2652 vlib_frame_t * from_frame)
2654 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2657 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2658 vlib_frame_t * from_frame)
2660 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2663 VLIB_REGISTER_NODE (tcp4_listen_node) = {
2664 .name = "tcp4-listen",
2665 /* Takes a vector of packets. */
2666 .vector_size = sizeof (u32),
2667 .n_errors = TCP_N_ERROR,
2668 .error_counters = tcp_input_error_counters,
2669 .format_trace = format_tcp_rx_trace_short,
2672 VLIB_REGISTER_NODE (tcp6_listen_node) = {
2673 .name = "tcp6-listen",
2674 /* Takes a vector of packets. */
2675 .vector_size = sizeof (u32),
2676 .n_errors = TCP_N_ERROR,
2677 .error_counters = tcp_input_error_counters,
2678 .format_trace = format_tcp_rx_trace_short,
2682 tcp46_drop_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2683 vlib_frame_t *frame, int is_ip4)
2685 u32 *from = vlib_frame_vector_args (frame);
2687 /* Error counters must be incremented by previous nodes */
2688 vlib_buffer_free (vm, from, frame->n_vectors);
2690 return frame->n_vectors;
2693 VLIB_NODE_FN (tcp4_drop_node)
2694 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2696 return tcp46_drop_inline (vm, node, from_frame, 1 /* is_ip4 */);
2699 VLIB_NODE_FN (tcp6_drop_node)
2700 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2702 return tcp46_drop_inline (vm, node, from_frame, 0 /* is_ip4 */);
2705 VLIB_REGISTER_NODE (tcp4_drop_node) = {
2706 .name = "tcp4-drop",
2707 .vector_size = sizeof (u32),
2708 .n_errors = TCP_N_ERROR,
2709 .error_counters = tcp_input_error_counters,
2712 VLIB_REGISTER_NODE (tcp6_drop_node) = {
2713 .name = "tcp6-drop",
2714 .vector_size = sizeof (u32),
2715 .n_errors = TCP_N_ERROR,
2716 .error_counters = tcp_input_error_counters,
2719 #define foreach_tcp4_input_next \
2720 _ (DROP, "tcp4-drop") \
2721 _ (LISTEN, "tcp4-listen") \
2722 _ (RCV_PROCESS, "tcp4-rcv-process") \
2723 _ (SYN_SENT, "tcp4-syn-sent") \
2724 _ (ESTABLISHED, "tcp4-established") \
2725 _ (RESET, "tcp4-reset") \
2726 _ (PUNT, "ip4-punt")
2728 #define foreach_tcp6_input_next \
2729 _ (DROP, "tcp6-drop") \
2730 _ (LISTEN, "tcp6-listen") \
2731 _ (RCV_PROCESS, "tcp6-rcv-process") \
2732 _ (SYN_SENT, "tcp6-syn-sent") \
2733 _ (ESTABLISHED, "tcp6-established") \
2734 _ (RESET, "tcp6-reset") \
2735 _ (PUNT, "ip6-punt")
2737 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2740 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2742 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2744 *next = TCP_INPUT_NEXT_DROP;
2746 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2748 *next = TCP_INPUT_NEXT_PUNT;
2749 *error = TCP_ERROR_PUNT;
2753 *next = TCP_INPUT_NEXT_RESET;
2754 *error = TCP_ERROR_NO_LISTENER;
2759 tcp_input_dispatch_buffer (tcp_main_t *tm, tcp_connection_t *tc,
2760 vlib_buffer_t *b, u16 *next, u16 *err_counters)
2766 tcp = tcp_buffer_hdr (b);
2767 flags = tcp->flags & filter_flags;
2768 *next = tm->dispatch_table[tc->state][flags].next;
2769 error = tm->dispatch_table[tc->state][flags].error;
2772 /* Track connection state when packet was received. It is required
2773 * for @ref tcp46_listen_inline to detect whether we reached
2774 * the node as a result of a SYN packet received while in time-wait
2775 * state. In this case the connection_index in vnet buffer will point
2776 * to the existing tcp connection and not the listener
2778 vnet_buffer (b)->tcp.flags = tc->state;
2780 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2782 tcp_inc_err_counter (err_counters, error, 1);
2783 if (error == TCP_ERROR_DISPATCH)
2784 clib_warning ("tcp conn %u disp error state %U flags %U",
2785 tc->c_c_index, format_tcp_state, tc->state,
2786 format_tcp_flags, (int) flags);
2791 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2792 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2794 u32 n_left_from, *from, thread_index = vm->thread_index;
2795 tcp_main_t *tm = vnet_get_tcp_main ();
2796 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2797 u16 nexts[VLIB_FRAME_SIZE], *next;
2798 u16 err_counters[TCP_N_ERROR] = { 0 };
2800 tcp_update_time_now (tcp_get_worker (thread_index));
2802 from = vlib_frame_vector_args (frame);
2803 n_left_from = frame->n_vectors;
2804 vlib_get_buffers (vm, from, bufs, n_left_from);
2809 while (n_left_from >= 4)
2811 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2812 tcp_connection_t *tc0, *tc1;
2815 vlib_prefetch_buffer_header (b[2], STORE);
2816 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2818 vlib_prefetch_buffer_header (b[3], STORE);
2819 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2822 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2824 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2826 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2829 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2831 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2832 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2834 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2835 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2837 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2838 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], err_counters);
2842 if (PREDICT_TRUE (tc0 != 0))
2844 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2845 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2846 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0],
2851 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2852 tcp_inc_err_counter (err_counters, error0, 1);
2855 if (PREDICT_TRUE (tc1 != 0))
2857 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2858 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2859 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1],
2864 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2865 tcp_inc_err_counter (err_counters, error1, 1);
2873 while (n_left_from > 0)
2875 tcp_connection_t *tc0;
2876 u32 error0 = TCP_ERROR_NO_LISTENER;
2878 if (n_left_from > 1)
2880 vlib_prefetch_buffer_header (b[1], STORE);
2881 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2884 next[0] = TCP_INPUT_NEXT_DROP;
2885 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2887 if (PREDICT_TRUE (tc0 != 0))
2889 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2890 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2891 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2895 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2896 tcp_inc_err_counter (err_counters, error0, 1);
2904 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2905 tcp_input_trace_frame (vm, node, bufs, nexts, frame->n_vectors, is_ip4);
2907 tcp_store_err_counters (input, err_counters);
2908 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2909 return frame->n_vectors;
2912 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2913 vlib_node_runtime_t * node,
2914 vlib_frame_t * from_frame)
2916 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2917 1 /* is_nolookup */ );
2920 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2921 vlib_node_runtime_t * node,
2922 vlib_frame_t * from_frame)
2924 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2925 1 /* is_nolookup */ );
2928 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2930 .name = "tcp4-input-nolookup",
2931 /* Takes a vector of packets. */
2932 .vector_size = sizeof (u32),
2933 .n_errors = TCP_N_ERROR,
2934 .error_counters = tcp_input_error_counters,
2935 .n_next_nodes = TCP_INPUT_N_NEXT,
2938 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2939 foreach_tcp4_input_next
2942 .format_buffer = format_tcp_header,
2943 .format_trace = format_tcp_rx_trace,
2946 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2948 .name = "tcp6-input-nolookup",
2949 /* Takes a vector of packets. */
2950 .vector_size = sizeof (u32),
2951 .n_errors = TCP_N_ERROR,
2952 .error_counters = tcp_input_error_counters,
2953 .n_next_nodes = TCP_INPUT_N_NEXT,
2956 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2957 foreach_tcp6_input_next
2960 .format_buffer = format_tcp_header,
2961 .format_trace = format_tcp_rx_trace,
2964 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2965 vlib_frame_t * from_frame)
2967 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2968 0 /* is_nolookup */ );
2971 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2972 vlib_frame_t * from_frame)
2974 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2975 0 /* is_nolookup */ );
2978 VLIB_REGISTER_NODE (tcp4_input_node) =
2980 .name = "tcp4-input",
2981 /* Takes a vector of packets. */
2982 .vector_size = sizeof (u32),
2983 .n_errors = TCP_N_ERROR,
2984 .error_counters = tcp_input_error_counters,
2985 .n_next_nodes = TCP_INPUT_N_NEXT,
2988 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2989 foreach_tcp4_input_next
2992 .format_buffer = format_tcp_header,
2993 .format_trace = format_tcp_rx_trace,
2996 VLIB_REGISTER_NODE (tcp6_input_node) =
2998 .name = "tcp6-input",
2999 /* Takes a vector of packets. */
3000 .vector_size = sizeof (u32),
3001 .n_errors = TCP_N_ERROR,
3002 .error_counters = tcp_input_error_counters,
3003 .n_next_nodes = TCP_INPUT_N_NEXT,
3006 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3007 foreach_tcp6_input_next
3010 .format_buffer = format_tcp_header,
3011 .format_trace = format_tcp_rx_trace,
3014 #ifndef CLIB_MARCH_VARIANT
3016 tcp_check_gso (tcp_connection_t *tc)
3018 tcp_check_tx_offload (tc, tc->c_is_ip4);
3022 tcp_dispatch_table_init (tcp_main_t * tm)
3025 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3026 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3028 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3029 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3032 #define _(t,f,n,e) \
3034 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3035 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3038 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3039 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3040 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3041 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3042 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3043 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3044 TCP_ERROR_ACK_INVALID);
3045 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3046 TCP_ERROR_SEGMENT_INVALID);
3047 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3048 TCP_ERROR_SEGMENT_INVALID);
3049 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3050 TCP_ERROR_INVALID_CONNECTION);
3051 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3052 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3053 TCP_ERROR_SEGMENT_INVALID);
3054 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3055 TCP_ERROR_SEGMENT_INVALID);
3056 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3057 TCP_ERROR_SEGMENT_INVALID);
3058 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3059 TCP_ERROR_SEGMENT_INVALID);
3060 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3061 TCP_ERROR_SEGMENT_INVALID);
3062 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3063 TCP_ERROR_SEGMENT_INVALID);
3064 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3065 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3066 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3067 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3068 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3069 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3071 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3072 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3074 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3076 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3077 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3078 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3079 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3081 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3083 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3084 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3085 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3087 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3088 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3089 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3090 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3091 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3092 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3093 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3094 /* SYN-ACK for a SYN */
3095 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3097 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3098 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3099 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3101 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3102 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3104 /* ACK for for established connection -> tcp-established. */
3105 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3106 /* FIN for for established connection -> tcp-established. */
3107 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3108 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3110 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3112 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3113 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3114 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3116 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3117 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3118 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3119 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3120 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3121 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3122 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3123 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3125 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3126 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3128 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3130 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3131 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3132 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3133 /* ACK or FIN-ACK to our FIN */
3134 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3135 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3137 /* FIN in reply to our FIN from the other side */
3138 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3139 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3140 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3142 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3143 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3144 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3145 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3146 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3147 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3148 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3150 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3151 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3152 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3153 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3155 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3157 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3158 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3159 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3160 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3162 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3163 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3164 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3165 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3167 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3169 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3170 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3171 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3172 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3174 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3175 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3177 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3179 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3180 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3181 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3183 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3184 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3185 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3186 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3187 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3188 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3189 /* FIN confirming that the peer (app) has closed */
3190 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3191 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3192 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3194 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3195 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3197 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3198 _ (FIN_WAIT_2, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3200 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3201 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3203 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3204 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3206 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3207 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3208 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3209 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3210 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3212 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3214 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3215 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3216 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3218 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3219 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3220 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3221 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3223 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3224 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3227 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3230 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3232 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3233 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3235 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3236 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3238 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3239 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3241 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3242 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3243 * incoming segment not containing a RST causes a RST to be sent in
3245 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3246 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3247 TCP_ERROR_CONNECTION_CLOSED);
3248 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3249 _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3250 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3251 TCP_ERROR_CONNECTION_CLOSED);
3255 static clib_error_t *
3256 tcp_input_init (vlib_main_t * vm)
3258 clib_error_t *error = 0;
3259 tcp_main_t *tm = vnet_get_tcp_main ();
3261 if ((error = vlib_call_init_function (vm, tcp_init)))
3264 /* Initialize dispatch table. */
3265 tcp_dispatch_table_init (tm);
3270 VLIB_INIT_FUNCTION (tcp_input_init);
3272 #endif /* CLIB_MARCH_VARIANT */
3275 * fd.io coding-style-patch-verification: ON
3278 * eval: (c-set-style "gnu")