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 */ );
1470 VLIB_REGISTER_NODE (tcp4_established_node) = {
1471 .name = "tcp4-established",
1472 /* Takes a vector of packets. */
1473 .vector_size = sizeof (u32),
1474 .n_errors = TCP_N_ERROR,
1475 .error_counters = tcp_input_error_counters,
1476 .format_trace = format_tcp_rx_trace_short,
1481 VLIB_REGISTER_NODE (tcp6_established_node) = {
1482 .name = "tcp6-established",
1483 /* Takes a vector of packets. */
1484 .vector_size = sizeof (u32),
1485 .n_errors = TCP_N_ERROR,
1486 .error_counters = tcp_input_error_counters,
1487 .format_trace = format_tcp_rx_trace_short,
1493 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1496 transport_connection_t *tmp = 0;
1503 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1506 u8 is_ip_valid = 0, val_l, val_r;
1508 if (tc->connection.is_ip4)
1510 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1512 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1513 &tc->connection.lcl_ip.ip4);
1514 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1515 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1516 &tc->connection.rmt_ip.ip4);
1517 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1518 is_ip_valid = val_l && val_r;
1522 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1524 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1525 &tc->connection.lcl_ip.ip6);
1526 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1527 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1528 &tc->connection.rmt_ip.ip6);
1529 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1530 is_ip_valid = val_l && val_r;
1533 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1534 && (tc->state == TCP_STATE_LISTEN
1535 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1539 handle = session_lookup_half_open_handle (&tc->connection);
1540 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1541 tc->c_proto, tc->c_is_ip4);
1545 if (tmp->lcl_port == hdr->dst_port
1546 && tmp->rmt_port == hdr->src_port)
1548 TCP_DBG ("half-open is valid!");
1557 * Lookup transport connection
1559 static tcp_connection_t *
1560 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1564 transport_connection_t *tconn;
1565 tcp_connection_t *tc;
1570 ip4 = vlib_buffer_get_current (b);
1571 tcp = ip4_next_header (ip4);
1572 tconn = session_lookup_connection_wt4 (fib_index,
1577 TRANSPORT_PROTO_TCP,
1578 thread_index, &is_filtered);
1579 tc = tcp_get_connection_from_transport (tconn);
1580 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1585 ip6 = vlib_buffer_get_current (b);
1586 tcp = ip6_next_header (ip6);
1587 tconn = session_lookup_connection_wt6 (fib_index,
1592 TRANSPORT_PROTO_TCP,
1593 thread_index, &is_filtered);
1594 tc = tcp_get_connection_from_transport (tconn);
1595 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1600 static tcp_connection_t *
1601 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1607 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1608 tcp_header_t *tcp = tcp_buffer_hdr (b);
1609 s = session_lookup_listener4 (fib_index,
1611 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1615 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1616 tcp_header_t *tcp = tcp_buffer_hdr (b);
1617 s = session_lookup_listener6 (fib_index,
1619 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1622 if (PREDICT_TRUE (s != 0))
1623 return tcp_get_connection_from_transport (transport_get_listener
1624 (TRANSPORT_PROTO_TCP,
1625 s->connection_index));
1631 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1632 u32 *from, u32 n_bufs)
1634 tcp_connection_t *tc = 0;
1639 for (i = 0; i < n_bufs; i++)
1641 b = vlib_get_buffer (vm, from[i]);
1642 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1645 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1646 t = vlib_add_trace (vm, node, b, sizeof (*t));
1647 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1652 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1654 vnet_main_t *vnm = vnet_get_main ();
1655 const dpo_id_t *dpo;
1656 const load_balance_t *lb;
1657 vnet_hw_interface_t *hw_if;
1658 u32 sw_if_idx, lb_idx;
1662 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1663 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1667 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1668 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1671 lb = load_balance_get (lb_idx);
1672 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1674 dpo = load_balance_get_bucket_i (lb, 0);
1676 sw_if_idx = dpo_get_urpf (dpo);
1677 if (PREDICT_FALSE (sw_if_idx == ~0))
1680 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1681 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1682 tc->cfg_flags |= TCP_CFG_F_TSO;
1686 tcp_input_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1687 vlib_buffer_t **bs, u16 *nexts, u32 n_bufs, u8 is_ip4)
1689 tcp_connection_t *tc;
1695 for (i = 0; i < n_bufs; i++)
1697 if (!(bs[i]->flags & VLIB_BUFFER_IS_TRACED))
1700 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
1701 if (nexts[i] == TCP_INPUT_NEXT_DROP || nexts[i] == TCP_INPUT_NEXT_PUNT ||
1702 nexts[i] == TCP_INPUT_NEXT_RESET)
1708 flags = vnet_buffer (bs[i])->tcp.flags;
1710 if (flags == TCP_STATE_LISTEN)
1711 tc = tcp_listener_get (vnet_buffer (bs[i])->tcp.connection_index);
1712 else if (flags == TCP_STATE_SYN_SENT)
1713 tc = tcp_half_open_connection_get (
1714 vnet_buffer (bs[i])->tcp.connection_index);
1716 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
1719 tcp = tcp_buffer_hdr (bs[i]);
1720 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
1725 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1726 vlib_frame_t *frame, int is_ip4)
1728 u32 n_left_from, *from, thread_index = vm->thread_index;
1729 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1730 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1732 from = vlib_frame_vector_args (frame);
1733 n_left_from = frame->n_vectors;
1735 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1736 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1738 vlib_get_buffers (vm, from, bufs, n_left_from);
1741 while (n_left_from > 0)
1743 u32 ack, seq, error = TCP_ERROR_NONE;
1744 tcp_connection_t *tc, *new_tc;
1747 tc = tcp_half_open_connection_get (
1748 vnet_buffer (b[0])->tcp.connection_index);
1749 if (PREDICT_FALSE (tc == 0))
1751 error = TCP_ERROR_INVALID_CONNECTION;
1755 /* Half-open completed or cancelled recently but the connection
1756 * was't removed yet by the owning thread */
1757 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1759 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1763 ack = vnet_buffer (b[0])->tcp.ack_number;
1764 seq = vnet_buffer (b[0])->tcp.seq_number;
1765 tcp = tcp_buffer_hdr (b[0]);
1767 /* Crude check to see if the connection handle does not match
1768 * the packet. Probably connection just switched to established */
1769 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1770 tcp->src_port != tc->c_rmt_port))
1772 error = TCP_ERROR_INVALID_CONNECTION;
1776 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1778 error = TCP_ERROR_SEGMENT_INVALID;
1782 /* SYNs consume sequence numbers */
1783 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1786 * 1. check the ACK bit
1790 * If the ACK bit is set
1791 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1792 * the RST bit is set, if so drop the segment and return)
1793 * <SEQ=SEG.ACK><CTL=RST>
1794 * and discard the segment. Return.
1795 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1799 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1802 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1803 error = TCP_ERROR_RCV_WND;
1807 /* Make sure ACK is valid */
1808 if (seq_gt (tc->snd_una, ack))
1810 error = TCP_ERROR_ACK_INVALID;
1816 * 2. check the RST bit
1821 /* If ACK is acceptable, signal client that peer is not
1822 * willing to accept connection and drop connection*/
1824 tcp_rcv_rst (wrk, tc);
1825 error = TCP_ERROR_RST_RCVD;
1830 * 3. check the security and precedence (skipped)
1834 * 4. check the SYN bit
1837 /* No SYN flag. Drop. */
1840 error = TCP_ERROR_SEGMENT_INVALID;
1845 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1847 error = TCP_ERROR_OPTIONS;
1851 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1852 * current thread pool. */
1853 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1854 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1856 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1858 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1860 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1861 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1864 if (tcp_opts_wscale (&new_tc->rcv_opts))
1865 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1867 new_tc->rcv_wscale = 0;
1869 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1870 << new_tc->snd_wscale;
1871 new_tc->snd_wl1 = seq;
1872 new_tc->snd_wl2 = ack;
1874 tcp_connection_init_vars (new_tc);
1876 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1877 if (PREDICT_TRUE (tcp_ack (tcp)))
1879 /* Our SYN is ACKed: we have iss < ack = snd_una */
1881 /* TODO Dequeue acknowledged segments if we support Fast Open */
1882 new_tc->snd_una = ack;
1883 new_tc->state = TCP_STATE_ESTABLISHED;
1885 /* Make sure las is initialized for the wnd computation */
1886 new_tc->rcv_las = new_tc->rcv_nxt;
1888 /* Notify app that we have connection. If session layer can't
1889 * allocate session send reset */
1890 if (session_stream_connect_notify (&new_tc->connection,
1893 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1894 tcp_program_cleanup (wrk, new_tc);
1895 new_tc->state = TCP_STATE_CLOSED;
1896 new_tc->c_s_index = ~0;
1897 error = TCP_ERROR_CREATE_SESSION_FAIL;
1901 transport_fifos_init_ooo (&new_tc->connection);
1902 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1903 /* Update rtt with the syn-ack sample */
1904 tcp_estimate_initial_rtt (new_tc);
1905 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1906 error = TCP_ERROR_SYN_ACKS_RCVD;
1908 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1911 new_tc->state = TCP_STATE_SYN_RCVD;
1913 /* Notify app that we have connection */
1914 if (session_stream_connect_notify (&new_tc->connection,
1917 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1918 tcp_program_cleanup (wrk, new_tc);
1919 new_tc->state = TCP_STATE_CLOSED;
1920 new_tc->c_s_index = ~0;
1921 TCP_EVT (TCP_EVT_RST_SENT, tc);
1922 error = TCP_ERROR_CREATE_SESSION_FAIL;
1926 transport_fifos_init_ooo (&new_tc->connection);
1927 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1929 tcp_init_snd_vars (new_tc);
1930 tcp_send_synack (new_tc);
1931 error = TCP_ERROR_SYNS_RCVD;
1935 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
1936 tcp_check_tx_offload (new_tc, is_ip4);
1938 /* Read data, if any */
1939 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
1941 clib_warning ("rcvd data in syn-sent");
1942 error = tcp_segment_rcv (wrk, new_tc, b[0]);
1943 if (error == TCP_ERROR_ACK_OK)
1944 error = TCP_ERROR_SYN_ACKS_RCVD;
1948 /* Send ack now instead of programming it because connection was
1949 * just established and it's not optional. */
1950 tcp_send_ack (new_tc);
1955 /* If this is not the owning thread, wait for syn retransmit to
1956 * expire and cleanup then */
1957 if (tcp_half_open_connection_cleanup (tc))
1958 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
1964 tcp_inc_counter (syn_sent, error, 1);
1967 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
1968 vlib_buffer_free (vm, from, frame->n_vectors);
1969 tcp_handle_disconnects (wrk);
1971 return frame->n_vectors;
1974 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
1975 vlib_node_runtime_t * node,
1976 vlib_frame_t * from_frame)
1978 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1981 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
1982 vlib_node_runtime_t * node,
1983 vlib_frame_t * from_frame)
1985 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1989 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
1991 .name = "tcp4-syn-sent",
1992 /* Takes a vector of packets. */
1993 .vector_size = sizeof (u32),
1994 .n_errors = TCP_N_ERROR,
1995 .error_counters = tcp_input_error_counters,
1996 .format_trace = format_tcp_rx_trace_short,
2001 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2003 .name = "tcp6-syn-sent",
2004 /* Takes a vector of packets. */
2005 .vector_size = sizeof (u32),
2006 .n_errors = TCP_N_ERROR,
2007 .error_counters = tcp_input_error_counters,
2008 .format_trace = format_tcp_rx_trace_short,
2013 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2014 u32 *from, u32 n_bufs)
2016 u32 thread_index = vm->thread_index;
2017 tcp_connection_t *tc = 0;
2022 for (i = 0; i < n_bufs; i++)
2024 b = vlib_get_buffer (vm, from[i]);
2025 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2027 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2029 t = vlib_add_trace (vm, node, b, sizeof (*t));
2030 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2035 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2036 * as per RFC793 p. 64
2039 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2040 vlib_frame_t *frame, int is_ip4)
2042 u32 thread_index = vm->thread_index, n_left_from, *from, max_deq;
2043 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2044 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2046 from = vlib_frame_vector_args (frame);
2047 n_left_from = frame->n_vectors;
2049 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2050 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2052 vlib_get_buffers (vm, from, bufs, n_left_from);
2055 while (n_left_from > 0)
2057 u32 error = TCP_ERROR_NONE;
2058 tcp_header_t *tcp = 0;
2059 tcp_connection_t *tc;
2062 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2064 if (PREDICT_FALSE (tc == 0))
2066 error = TCP_ERROR_INVALID_CONNECTION;
2070 tcp = tcp_buffer_hdr (b[0]);
2071 is_fin = tcp_is_fin (tcp);
2075 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2077 tcp_connection_t *tmp;
2078 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2080 if (tmp->state != tc->state)
2082 if (tc->state != TCP_STATE_CLOSED)
2083 clib_warning ("state changed");
2090 * Special treatment for CLOSED
2092 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2094 error = TCP_ERROR_CONNECTION_CLOSED;
2099 * For all other states (except LISTEN)
2102 /* 1-4: check SEQ, RST, SYN */
2103 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2106 /* 5: check the ACK field */
2109 case TCP_STATE_SYN_RCVD:
2111 * If the segment acknowledgment is not acceptable, form a
2113 * <SEQ=SEG.ACK><CTL=RST>
2116 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2118 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2119 error = TCP_ERROR_SEGMENT_INVALID;
2123 /* Avoid notifying app if connection is about to be closed */
2124 if (PREDICT_FALSE (is_fin))
2127 /* Update rtt and rto */
2128 tcp_estimate_initial_rtt (tc);
2129 tcp_connection_tx_pacer_update (tc);
2131 /* Switch state to ESTABLISHED */
2132 tc->state = TCP_STATE_ESTABLISHED;
2133 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2135 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2136 tcp_check_tx_offload (tc, is_ip4);
2138 /* Initialize session variables */
2139 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2140 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2141 << tc->rcv_opts.wscale;
2142 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2143 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2145 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2146 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2147 if (session_stream_accept_notify (&tc->connection))
2149 error = TCP_ERROR_MSG_QUEUE_FULL;
2150 tcp_send_reset (tc);
2151 session_transport_delete_notify (&tc->connection);
2152 tcp_connection_cleanup (tc);
2155 error = TCP_ERROR_CONN_ACCEPTED;
2157 case TCP_STATE_ESTABLISHED:
2158 /* We can get packets in established state here because they
2159 * were enqueued before state change */
2160 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2164 case TCP_STATE_FIN_WAIT_1:
2165 /* In addition to the processing for the ESTABLISHED state, if
2166 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2167 * continue processing in that state. */
2168 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2171 /* Still have to send the FIN */
2172 if (tc->flags & TCP_CONN_FINPNDG)
2174 /* TX fifo finally drained */
2175 max_deq = transport_max_tx_dequeue (&tc->connection);
2176 if (max_deq <= tc->burst_acked)
2178 /* If a fin was received and data was acked extend wait */
2179 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2180 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2181 tcp_cfg.closewait_time);
2183 /* If FIN is ACKed */
2184 else if (tc->snd_una == tc->snd_nxt)
2186 /* Stop all retransmit timers because we have nothing more
2188 tcp_connection_timers_reset (tc);
2190 /* We already have a FIN but didn't transition to CLOSING
2191 * because of outstanding tx data. Close the connection. */
2192 if (tc->flags & TCP_CONN_FINRCVD)
2194 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2195 session_transport_closed_notify (&tc->connection);
2196 tcp_program_cleanup (wrk, tc);
2200 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2201 /* Enable waitclose because we're willing to wait for peer's
2202 * FIN but not indefinitely. */
2203 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2204 tcp_cfg.finwait2_time);
2206 /* Don't try to deq the FIN acked */
2207 if (tc->burst_acked > 1)
2208 session_tx_fifo_dequeue_drop (&tc->connection,
2209 tc->burst_acked - 1);
2210 tc->burst_acked = 0;
2213 case TCP_STATE_FIN_WAIT_2:
2214 /* In addition to the processing for the ESTABLISHED state, if
2215 * the retransmission queue is empty, the user's CLOSE can be
2216 * acknowledged ("ok") but do not delete the TCB. */
2217 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2219 tc->burst_acked = 0;
2221 case TCP_STATE_CLOSE_WAIT:
2222 /* Do the same processing as for the ESTABLISHED state. */
2223 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2226 if (!(tc->flags & TCP_CONN_FINPNDG))
2229 /* Still have outstanding tx data */
2230 max_deq = transport_max_tx_dequeue (&tc->connection);
2231 if (max_deq > tc->burst_acked)
2235 tcp_connection_timers_reset (tc);
2236 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2237 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2238 tcp_cfg.lastack_time);
2240 case TCP_STATE_CLOSING:
2241 /* In addition to the processing for the ESTABLISHED state, if
2242 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2243 * otherwise ignore the segment. */
2244 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2247 if (tc->snd_una != tc->snd_nxt)
2250 tcp_connection_timers_reset (tc);
2251 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2252 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2253 tcp_cfg.timewait_time);
2254 session_transport_closed_notify (&tc->connection);
2258 case TCP_STATE_LAST_ACK:
2259 /* The only thing that [should] arrive in this state is an
2260 * acknowledgment of our FIN. If our FIN is now acknowledged,
2261 * delete the TCB, enter the CLOSED state, and return. */
2263 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2266 /* Apparently our ACK for the peer's FIN was lost */
2267 if (is_fin && tc->snd_una != tc->snd_nxt)
2273 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2274 session_transport_closed_notify (&tc->connection);
2276 /* Don't free the connection from the data path since
2277 * we can't ensure that we have no packets already enqueued
2278 * to output. Rely instead on the waitclose timer */
2279 tcp_connection_timers_reset (tc);
2280 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2285 case TCP_STATE_TIME_WAIT:
2286 /* The only thing that can arrive in this state is a
2287 * retransmission of the remote FIN. Acknowledge it, and restart
2288 * the 2 MSL timeout. */
2290 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2296 tcp_program_ack (tc);
2297 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2298 tcp_cfg.timewait_time);
2306 /* 6: check the URG bit TODO */
2308 /* 7: process the segment text */
2311 case TCP_STATE_ESTABLISHED:
2312 case TCP_STATE_FIN_WAIT_1:
2313 case TCP_STATE_FIN_WAIT_2:
2314 if (vnet_buffer (b[0])->tcp.data_len)
2315 error = tcp_segment_rcv (wrk, tc, b[0]);
2316 /* Don't accept out of order fins lower */
2317 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2320 case TCP_STATE_CLOSE_WAIT:
2321 case TCP_STATE_CLOSING:
2322 case TCP_STATE_LAST_ACK:
2323 case TCP_STATE_TIME_WAIT:
2324 /* This should not occur, since a FIN has been received from the
2325 * remote side. Ignore the segment text. */
2329 /* 8: check the FIN bit */
2333 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2337 case TCP_STATE_ESTABLISHED:
2338 /* Account for the FIN and send ack */
2340 tcp_program_ack (tc);
2341 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2342 tcp_program_disconnect (wrk, tc);
2343 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2344 tcp_cfg.closewait_time);
2346 case TCP_STATE_SYN_RCVD:
2347 /* Send FIN-ACK and enter TIME-WAIT, as opposed to LAST-ACK,
2348 * because the app was not notified yet and we want to avoid
2349 * session state transitions to ensure cleanup does not
2350 * propagate to app. */
2351 tcp_connection_timers_reset (tc);
2354 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2355 tcp_program_cleanup (wrk, tc);
2357 case TCP_STATE_CLOSE_WAIT:
2358 case TCP_STATE_CLOSING:
2359 case TCP_STATE_LAST_ACK:
2362 case TCP_STATE_FIN_WAIT_1:
2365 if (tc->flags & TCP_CONN_FINPNDG)
2367 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2368 * sending it. Since we already received a fin, do not wait
2370 tc->flags |= TCP_CONN_FINRCVD;
2371 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2372 tcp_cfg.closewait_time);
2376 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2377 tcp_program_ack (tc);
2378 /* Wait for ACK for our FIN but not forever */
2379 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2380 tcp_cfg.closing_time);
2383 case TCP_STATE_FIN_WAIT_2:
2384 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2386 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2387 tcp_connection_timers_reset (tc);
2388 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2389 tcp_cfg.timewait_time);
2390 tcp_program_ack (tc);
2391 session_transport_closed_notify (&tc->connection);
2393 case TCP_STATE_TIME_WAIT:
2394 /* Remain in the TIME-WAIT state. Restart the time-wait
2397 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2398 tcp_cfg.timewait_time);
2401 error = TCP_ERROR_FIN_RCVD;
2407 tcp_inc_counter (rcv_process, error, 1);
2410 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2411 tcp_handle_postponed_dequeues (wrk);
2412 tcp_handle_disconnects (wrk);
2413 vlib_buffer_free (vm, from, frame->n_vectors);
2415 return frame->n_vectors;
2418 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2419 vlib_node_runtime_t * node,
2420 vlib_frame_t * from_frame)
2422 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2425 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2426 vlib_node_runtime_t * node,
2427 vlib_frame_t * from_frame)
2429 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2433 VLIB_REGISTER_NODE (tcp4_rcv_process_node) = {
2434 .name = "tcp4-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,
2444 VLIB_REGISTER_NODE (tcp6_rcv_process_node) = {
2445 .name = "tcp6-rcv-process",
2446 /* Takes a vector of packets. */
2447 .vector_size = sizeof (u32),
2448 .n_errors = TCP_N_ERROR,
2449 .error_counters = tcp_input_error_counters,
2450 .format_trace = format_tcp_rx_trace_short,
2455 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2456 u32 *to_next, u32 n_bufs)
2458 tcp_connection_t *tc = 0;
2463 for (i = 0; i < n_bufs; i++)
2465 b = vlib_get_buffer (vm, to_next[i]);
2466 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2468 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2469 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2470 t = vlib_add_trace (vm, node, b, sizeof (*t));
2471 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2476 * SYN received in TIME-WAIT state.
2479 * "When a connection is [...] on TIME-WAIT state [...]
2480 * [a TCP] MAY accept a new SYN from the remote TCP to
2481 * reopen the connection directly, if it:
2483 * (1) assigns its initial sequence number for the new
2484 * connection to be larger than the largest sequence
2485 * number it used on the previous connection incarnation,
2488 * (2) returns to TIME-WAIT state if the SYN turns out
2489 * to be an old duplicate".
2491 * The function returns true if the syn can be accepted during
2492 * connection time-wait (port reuse). In this case the function
2493 * also calculates what the iss should be for the new connection.
2496 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2498 int paws_reject = tcp_segment_check_paws (tc);
2502 /* Check that the SYN arrived out of window. We accept it */
2504 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2505 (tcp_opts_tstamp (&tc->rcv_opts) &&
2506 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2508 /* Set the iss of the new connection to be the largest sequence number
2509 * the old peer would have accepted and add some random number
2511 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2512 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2522 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2523 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2524 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2525 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2531 * LISTEN state processing as per RFC 793 p. 65
2534 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2535 vlib_frame_t *frame, int is_ip4)
2537 u32 n_left_from, *from, n_syns = 0;
2538 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2539 u32 thread_index = vm->thread_index;
2542 from = vlib_frame_vector_args (frame);
2543 n_left_from = frame->n_vectors;
2545 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2546 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2548 vlib_get_buffers (vm, from, bufs, n_left_from);
2551 while (n_left_from > 0)
2553 tcp_connection_t *lc, *child;
2555 /* Flags initialized with connection state after lookup */
2556 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2558 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2560 /* Probably we are in time-wait or closed state */
2563 tcp_connection_t *tc;
2564 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2566 if (tc->state != TCP_STATE_TIME_WAIT)
2568 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2572 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2574 /* This SYN can't be accepted */
2575 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2579 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2580 /* clean up the old session */
2581 tcp_connection_del (tc);
2582 /* listener was cleaned up */
2585 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
2590 /* Make sure connection wasn't just created */
2592 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2593 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2595 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2599 /* Create child session. For syn-flood protection use filter */
2601 /* 1. first check for an RST: handled by input dispatch */
2603 /* 2. second check for an ACK: handled by input dispatch */
2605 /* 3. check for a SYN (did that already) */
2607 /* Create child session and send SYN-ACK */
2608 child = tcp_connection_alloc (thread_index);
2610 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2612 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
2613 tcp_connection_free (child);
2617 tcp_init_w_buffer (child, b[0], is_ip4);
2619 child->state = TCP_STATE_SYN_RCVD;
2620 child->c_fib_index = lc->c_fib_index;
2621 child->cc_algo = lc->cc_algo;
2623 /* In the regular case, the tw_iss will be zero, but
2624 * in the special case of syn arriving in time_wait state, the value
2625 * will be set according to rfc 1122
2627 child->iss = tw_iss;
2628 tcp_connection_init_vars (child);
2629 child->rto = TCP_RTO_MIN;
2632 * This initializes elog track, must be done before synack.
2633 * We also do it before possible tcp_connection_cleanup() as it
2634 * generates TCP_EVT_DELETE event.
2636 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2638 if (session_stream_accept (&child->connection, lc->c_s_index,
2639 lc->c_thread_index, 0 /* notify */ ))
2641 tcp_connection_cleanup (child);
2642 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
2646 transport_fifos_init_ooo (&child->connection);
2647 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2649 tcp_send_synack (child);
2657 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2658 vlib_buffer_free (vm, from, frame->n_vectors);
2660 return frame->n_vectors;
2663 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2664 vlib_frame_t * from_frame)
2666 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2669 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2670 vlib_frame_t * from_frame)
2672 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2676 VLIB_REGISTER_NODE (tcp4_listen_node) = {
2677 .name = "tcp4-listen",
2678 /* Takes a vector of packets. */
2679 .vector_size = sizeof (u32),
2680 .n_errors = TCP_N_ERROR,
2681 .error_counters = tcp_input_error_counters,
2682 .format_trace = format_tcp_rx_trace_short,
2687 VLIB_REGISTER_NODE (tcp6_listen_node) = {
2688 .name = "tcp6-listen",
2689 /* Takes a vector of packets. */
2690 .vector_size = sizeof (u32),
2691 .n_errors = TCP_N_ERROR,
2692 .error_counters = tcp_input_error_counters,
2693 .format_trace = format_tcp_rx_trace_short,
2698 tcp46_drop_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2699 vlib_frame_t *frame, int is_ip4)
2701 u32 *from = vlib_frame_vector_args (frame);
2703 /* Error counters must be incremented by previous nodes */
2704 vlib_buffer_free (vm, from, frame->n_vectors);
2706 return frame->n_vectors;
2709 VLIB_NODE_FN (tcp4_drop_node)
2710 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2712 return tcp46_drop_inline (vm, node, from_frame, 1 /* is_ip4 */);
2715 VLIB_NODE_FN (tcp6_drop_node)
2716 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2718 return tcp46_drop_inline (vm, node, from_frame, 0 /* is_ip4 */);
2721 VLIB_REGISTER_NODE (tcp4_drop_node) = {
2722 .name = "tcp4-drop",
2723 .vector_size = sizeof (u32),
2724 .n_errors = TCP_N_ERROR,
2725 .error_counters = tcp_input_error_counters,
2728 VLIB_REGISTER_NODE (tcp6_drop_node) = {
2729 .name = "tcp6-drop",
2730 .vector_size = sizeof (u32),
2731 .n_errors = TCP_N_ERROR,
2732 .error_counters = tcp_input_error_counters,
2735 #define foreach_tcp4_input_next \
2736 _ (DROP, "tcp4-drop") \
2737 _ (LISTEN, "tcp4-listen") \
2738 _ (RCV_PROCESS, "tcp4-rcv-process") \
2739 _ (SYN_SENT, "tcp4-syn-sent") \
2740 _ (ESTABLISHED, "tcp4-established") \
2741 _ (RESET, "tcp4-reset") \
2742 _ (PUNT, "ip4-punt")
2744 #define foreach_tcp6_input_next \
2745 _ (DROP, "tcp6-drop") \
2746 _ (LISTEN, "tcp6-listen") \
2747 _ (RCV_PROCESS, "tcp6-rcv-process") \
2748 _ (SYN_SENT, "tcp6-syn-sent") \
2749 _ (ESTABLISHED, "tcp6-established") \
2750 _ (RESET, "tcp6-reset") \
2751 _ (PUNT, "ip6-punt")
2753 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2756 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2758 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2760 *next = TCP_INPUT_NEXT_DROP;
2762 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2764 *next = TCP_INPUT_NEXT_PUNT;
2765 *error = TCP_ERROR_PUNT;
2769 *next = TCP_INPUT_NEXT_RESET;
2770 *error = TCP_ERROR_NO_LISTENER;
2775 tcp_input_dispatch_buffer (tcp_main_t *tm, tcp_connection_t *tc,
2776 vlib_buffer_t *b, u16 *next, u16 *err_counters)
2782 tcp = tcp_buffer_hdr (b);
2783 flags = tcp->flags & filter_flags;
2784 *next = tm->dispatch_table[tc->state][flags].next;
2785 error = tm->dispatch_table[tc->state][flags].error;
2788 /* Track connection state when packet was received. It is required
2789 * for @ref tcp46_listen_inline to detect whether we reached
2790 * the node as a result of a SYN packet received while in time-wait
2791 * state. In this case the connection_index in vnet buffer will point
2792 * to the existing tcp connection and not the listener
2794 vnet_buffer (b)->tcp.flags = tc->state;
2796 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2798 tcp_inc_err_counter (err_counters, error, 1);
2799 if (error == TCP_ERROR_DISPATCH)
2800 clib_warning ("tcp conn %u disp error state %U flags %U",
2801 tc->c_c_index, format_tcp_state, tc->state,
2802 format_tcp_flags, (int) flags);
2807 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2808 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2810 u32 n_left_from, *from, thread_index = vm->thread_index;
2811 tcp_main_t *tm = vnet_get_tcp_main ();
2812 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2813 u16 nexts[VLIB_FRAME_SIZE], *next;
2814 u16 err_counters[TCP_N_ERROR] = { 0 };
2816 tcp_update_time_now (tcp_get_worker (thread_index));
2818 from = vlib_frame_vector_args (frame);
2819 n_left_from = frame->n_vectors;
2820 vlib_get_buffers (vm, from, bufs, n_left_from);
2825 while (n_left_from >= 4)
2827 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2828 tcp_connection_t *tc0, *tc1;
2831 vlib_prefetch_buffer_header (b[2], STORE);
2832 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2834 vlib_prefetch_buffer_header (b[3], STORE);
2835 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2838 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2840 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2842 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2845 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2847 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2848 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2850 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2851 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2853 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2854 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], err_counters);
2858 if (PREDICT_TRUE (tc0 != 0))
2860 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2861 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2862 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0],
2867 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2868 tcp_inc_err_counter (err_counters, error0, 1);
2871 if (PREDICT_TRUE (tc1 != 0))
2873 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2874 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2875 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1],
2880 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2881 tcp_inc_err_counter (err_counters, error1, 1);
2889 while (n_left_from > 0)
2891 tcp_connection_t *tc0;
2892 u32 error0 = TCP_ERROR_NO_LISTENER;
2894 if (n_left_from > 1)
2896 vlib_prefetch_buffer_header (b[1], STORE);
2897 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2900 next[0] = TCP_INPUT_NEXT_DROP;
2901 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2903 if (PREDICT_TRUE (tc0 != 0))
2905 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2906 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2907 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2911 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2912 tcp_inc_err_counter (err_counters, error0, 1);
2920 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2921 tcp_input_trace_frame (vm, node, bufs, nexts, frame->n_vectors, is_ip4);
2923 tcp_store_err_counters (input, err_counters);
2924 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2925 return frame->n_vectors;
2928 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2929 vlib_node_runtime_t * node,
2930 vlib_frame_t * from_frame)
2932 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2933 1 /* is_nolookup */ );
2936 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2937 vlib_node_runtime_t * node,
2938 vlib_frame_t * from_frame)
2940 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2941 1 /* is_nolookup */ );
2945 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2947 .name = "tcp4-input-nolookup",
2948 /* Takes a vector of packets. */
2949 .vector_size = sizeof (u32),
2950 .n_errors = TCP_N_ERROR,
2951 .error_counters = tcp_input_error_counters,
2952 .n_next_nodes = TCP_INPUT_N_NEXT,
2955 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2956 foreach_tcp4_input_next
2959 .format_buffer = format_tcp_header,
2960 .format_trace = format_tcp_rx_trace,
2965 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2967 .name = "tcp6-input-nolookup",
2968 /* Takes a vector of packets. */
2969 .vector_size = sizeof (u32),
2970 .n_errors = TCP_N_ERROR,
2971 .error_counters = tcp_input_error_counters,
2972 .n_next_nodes = TCP_INPUT_N_NEXT,
2975 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2976 foreach_tcp6_input_next
2979 .format_buffer = format_tcp_header,
2980 .format_trace = format_tcp_rx_trace,
2984 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2985 vlib_frame_t * from_frame)
2987 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2988 0 /* is_nolookup */ );
2991 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2992 vlib_frame_t * from_frame)
2994 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2995 0 /* is_nolookup */ );
2999 VLIB_REGISTER_NODE (tcp4_input_node) =
3001 .name = "tcp4-input",
3002 /* Takes a vector of packets. */
3003 .vector_size = sizeof (u32),
3004 .n_errors = TCP_N_ERROR,
3005 .error_counters = tcp_input_error_counters,
3006 .n_next_nodes = TCP_INPUT_N_NEXT,
3009 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3010 foreach_tcp4_input_next
3013 .format_buffer = format_tcp_header,
3014 .format_trace = format_tcp_rx_trace,
3019 VLIB_REGISTER_NODE (tcp6_input_node) =
3021 .name = "tcp6-input",
3022 /* Takes a vector of packets. */
3023 .vector_size = sizeof (u32),
3024 .n_errors = TCP_N_ERROR,
3025 .error_counters = tcp_input_error_counters,
3026 .n_next_nodes = TCP_INPUT_N_NEXT,
3029 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3030 foreach_tcp6_input_next
3033 .format_buffer = format_tcp_header,
3034 .format_trace = format_tcp_rx_trace,
3038 #ifndef CLIB_MARCH_VARIANT
3040 tcp_check_gso (tcp_connection_t *tc)
3042 tcp_check_tx_offload (tc, tc->c_is_ip4);
3046 tcp_dispatch_table_init (tcp_main_t * tm)
3049 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3050 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3052 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3053 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3056 #define _(t,f,n,e) \
3058 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3059 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3062 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3063 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3064 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3065 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3066 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3067 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3068 TCP_ERROR_ACK_INVALID);
3069 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3070 TCP_ERROR_SEGMENT_INVALID);
3071 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3072 TCP_ERROR_SEGMENT_INVALID);
3073 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3074 TCP_ERROR_INVALID_CONNECTION);
3075 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3076 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3077 TCP_ERROR_SEGMENT_INVALID);
3078 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3079 TCP_ERROR_SEGMENT_INVALID);
3080 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3081 TCP_ERROR_SEGMENT_INVALID);
3082 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3083 TCP_ERROR_SEGMENT_INVALID);
3084 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3085 TCP_ERROR_SEGMENT_INVALID);
3086 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3087 TCP_ERROR_SEGMENT_INVALID);
3088 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3089 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3090 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3091 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3092 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3093 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3095 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3096 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3098 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3100 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3101 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3102 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3103 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3105 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3107 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3108 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3109 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3111 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3112 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3113 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3114 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3115 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3116 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3117 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3118 /* SYN-ACK for a SYN */
3119 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3121 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3122 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3123 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3125 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3126 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3128 /* ACK for for established connection -> tcp-established. */
3129 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3130 /* FIN for for established connection -> tcp-established. */
3131 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3132 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3134 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3136 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3137 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3138 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3140 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3141 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3142 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3143 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3144 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3145 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3146 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3147 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3149 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3150 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3152 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3154 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3155 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3156 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3157 /* ACK or FIN-ACK to our FIN */
3158 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3159 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3161 /* FIN in reply to our FIN from the other side */
3162 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3163 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3164 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3166 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3167 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3168 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3169 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3170 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3171 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3172 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3174 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3175 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3176 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3177 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3179 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3181 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3182 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3183 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3184 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3186 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3187 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3188 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3189 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3191 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3193 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3194 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3195 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3196 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3198 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3199 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3201 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3203 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3204 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3205 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3207 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3208 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3209 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3210 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3211 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3212 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3213 /* FIN confirming that the peer (app) has closed */
3214 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3215 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3216 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3218 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3221 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _ (FIN_WAIT_2, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3227 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3230 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3231 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3232 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3233 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3236 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3238 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3239 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3240 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3242 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3243 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3244 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3245 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3246 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3247 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3248 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3249 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3251 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3252 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3254 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3256 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3257 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3258 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3259 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3260 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3262 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3263 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3265 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3266 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3267 * incoming segment not containing a RST causes a RST to be sent in
3269 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3270 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3271 TCP_ERROR_CONNECTION_CLOSED);
3272 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3273 _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3274 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3275 TCP_ERROR_CONNECTION_CLOSED);
3279 static clib_error_t *
3280 tcp_input_init (vlib_main_t * vm)
3282 clib_error_t *error = 0;
3283 tcp_main_t *tm = vnet_get_tcp_main ();
3285 if ((error = vlib_call_init_function (vm, tcp_init)))
3288 /* Initialize dispatch table. */
3289 tcp_dispatch_table_init (tm);
3294 VLIB_INIT_FUNCTION (tcp_input_init);
3296 #endif /* CLIB_MARCH_VARIANT */
3299 * fd.io coding-style-patch-verification: ON
3302 * eval: (c-set-style "gnu")