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 char *tcp_error_strings[] = {
25 #define tcp_error(n,s) s,
26 #include <vnet/tcp/tcp_error.def>
30 /* All TCP nodes have the same outgoing arcs */
31 #define foreach_tcp_state_next \
32 _ (DROP4, "ip4-drop") \
33 _ (DROP6, "ip6-drop") \
34 _ (TCP4_OUTPUT, "tcp4-output") \
35 _ (TCP6_OUTPUT, "tcp6-output")
37 typedef enum _tcp_established_next
39 #define _(s,n) TCP_ESTABLISHED_NEXT_##s,
40 foreach_tcp_state_next
42 TCP_ESTABLISHED_N_NEXT,
43 } tcp_established_next_t;
45 typedef enum _tcp_rcv_process_next
47 #define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
48 foreach_tcp_state_next
50 TCP_RCV_PROCESS_N_NEXT,
51 } tcp_rcv_process_next_t;
53 typedef enum _tcp_syn_sent_next
55 #define _(s,n) TCP_SYN_SENT_NEXT_##s,
56 foreach_tcp_state_next
59 } tcp_syn_sent_next_t;
61 typedef enum _tcp_listen_next
63 #define _(s,n) TCP_LISTEN_NEXT_##s,
64 foreach_tcp_state_next
69 /* Generic, state independent indices */
70 typedef enum _tcp_state_next
72 #define _(s,n) TCP_NEXT_##s,
73 foreach_tcp_state_next
78 #define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
79 : TCP_NEXT_TCP6_OUTPUT)
81 #define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
85 * Validate segment sequence number. As per RFC793:
87 * Segment Receive Test
89 * ------- ------- -------------------------------------------
90 * 0 0 SEG.SEQ = RCV.NXT
91 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
93 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
94 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
96 * This ultimately consists in checking if segment falls within the window.
97 * The one important difference compared to RFC793 is that we use rcv_las,
98 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
99 * peer's reference when computing our receive window.
102 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
103 * however, is too strict when we have retransmits. Instead we just check that
104 * the seq is not beyond the right edge and that the end of the segment is not
105 * less than the left edge.
107 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
108 * use rcv_nxt in the right edge window test instead of rcv_las.
112 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
114 return (seq_geq (end_seq, tc->rcv_las)
115 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
119 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
120 * timestamp to echo and it's less than tsval_recent, drop segment
121 * but still send an ACK in order to retain TCP's mechanism for detecting
122 * and recovering from half-open connections
124 * Or at least that's what the theory says. It seems that this might not work
125 * very well with packet reordering and fast retransmit. XXX
128 tcp_segment_check_paws (tcp_connection_t * tc)
130 return tcp_opts_tstamp (&tc->rcv_opts)
131 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
135 * Update tsval recent
138 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
141 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
142 * of an incoming segment:
143 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
144 * then the TSval from the segment is copied to TS.Recent;
145 * otherwise, the TSval is ignored.
147 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
148 && seq_leq (tc->rcv_las, seq_end))
150 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
151 tc->tsval_recent = tc->rcv_opts.tsval;
152 tc->tsval_recent_age = tcp_time_now_w_thread (tc->c_thread_index);
157 tcp_handle_rst (tcp_connection_t * tc)
159 switch (tc->rst_state)
161 case TCP_STATE_SYN_RCVD:
162 /* Cleanup everything. App wasn't notified yet */
163 session_transport_delete_notify (&tc->connection);
164 tcp_connection_cleanup (tc);
166 case TCP_STATE_SYN_SENT:
167 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
168 tcp_connection_cleanup (tc);
170 case TCP_STATE_ESTABLISHED:
171 session_transport_reset_notify (&tc->connection);
172 session_transport_closed_notify (&tc->connection);
174 case TCP_STATE_CLOSE_WAIT:
175 case TCP_STATE_FIN_WAIT_1:
176 case TCP_STATE_FIN_WAIT_2:
177 case TCP_STATE_CLOSING:
178 case TCP_STATE_LAST_ACK:
179 session_transport_closed_notify (&tc->connection);
181 case TCP_STATE_CLOSED:
182 case TCP_STATE_TIME_WAIT:
185 TCP_DBG ("reset state: %u", tc->state);
190 tcp_program_reset_ntf (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
192 if (!tcp_disconnect_pending (tc))
194 tc->rst_state = tc->state;
195 vec_add1 (wrk->pending_resets, tc->c_c_index);
196 tcp_disconnect_pending_on (tc);
201 * Handle reset packet
203 * Programs disconnect/reset notification that should be sent
204 * later by calling @ref tcp_handle_disconnects
207 tcp_rcv_rst (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
209 TCP_EVT (TCP_EVT_RST_RCVD, tc);
212 case TCP_STATE_SYN_RCVD:
213 tcp_program_reset_ntf (wrk, tc);
214 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
216 case TCP_STATE_SYN_SENT:
217 /* Do not program ntf because the connection is half-open */
220 case TCP_STATE_ESTABLISHED:
221 tcp_connection_timers_reset (tc);
222 tcp_cong_recovery_off (tc);
223 tcp_program_reset_ntf (wrk, tc);
224 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
225 tcp_program_cleanup (wrk, tc);
227 case TCP_STATE_CLOSE_WAIT:
228 case TCP_STATE_FIN_WAIT_1:
229 case TCP_STATE_FIN_WAIT_2:
230 case TCP_STATE_CLOSING:
231 case TCP_STATE_LAST_ACK:
232 tcp_connection_timers_reset (tc);
233 tcp_cong_recovery_off (tc);
234 tcp_program_reset_ntf (wrk, tc);
235 /* Make sure we mark the session as closed. In some states we may
236 * be still trying to send data */
237 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
238 tcp_program_cleanup (wrk, tc);
240 case TCP_STATE_CLOSED:
241 case TCP_STATE_TIME_WAIT:
244 TCP_DBG ("reset state: %u", tc->state);
249 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
251 * It first verifies if segment has a wrapped sequence number (PAWS) and then
252 * does the processing associated to the first four steps (ignoring security
253 * and precedence): sequence number, rst bit and syn bit checks.
255 * @return 0 if segments passes validation.
258 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
259 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
261 /* We could get a burst of RSTs interleaved with acks */
262 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
264 tcp_send_reset (tc0);
265 *error0 = TCP_ERROR_CONNECTION_CLOSED;
269 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
271 *error0 = TCP_ERROR_SEGMENT_INVALID;
275 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
277 *error0 = TCP_ERROR_OPTIONS;
281 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
283 *error0 = TCP_ERROR_PAWS;
284 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
285 vnet_buffer (b0)->tcp.seq_end);
287 /* If it just so happens that a segment updates tsval_recent for a
288 * segment over 24 days old, invalidate tsval_recent. */
289 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
290 tcp_time_now_w_thread (tc0->c_thread_index)))
292 tc0->tsval_recent = tc0->rcv_opts.tsval;
293 clib_warning ("paws failed: 24-day old segment");
295 /* Drop after ack if not rst. Resets can fail paws check as per
296 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
297 * be subjected to the PAWS check by verifying an acceptable value in
299 else if (!tcp_rst (th0))
301 tcp_program_ack (tc0);
302 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
307 /* 1st: check sequence number */
308 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
309 vnet_buffer (b0)->tcp.seq_end))
311 /* SYN/SYN-ACK retransmit */
313 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
315 tcp_options_parse (th0, &tc0->rcv_opts, 1);
316 if (tc0->state == TCP_STATE_SYN_RCVD)
318 tcp_send_synack (tc0);
319 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
320 *error0 = TCP_ERROR_SYNS_RCVD;
324 tcp_program_ack (tc0);
325 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
326 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
331 /* If our window is 0 and the packet is in sequence, let it pass
332 * through for ack processing. It should be dropped later. */
333 if (tc0->rcv_wnd < tc0->snd_mss
334 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
337 /* If we entered recovery and peer did so as well, there's a chance that
338 * dup acks won't be acceptable on either end because seq_end may be less
339 * than rcv_las. This can happen if acks are lost in both directions. */
340 if (tcp_in_recovery (tc0)
341 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
342 tc0->rcv_las - tc0->rcv_wnd)
343 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
344 tc0->rcv_nxt + tc0->rcv_wnd))
347 *error0 = TCP_ERROR_RCV_WND;
349 /* If we advertised a zero rcv_wnd and the segment is in the past or the
350 * next one that we expect, it is probably a window probe */
351 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
352 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
353 tc0->rcv_las + tc0->rcv_opts.mss))
354 *error0 = TCP_ERROR_ZERO_RWND;
356 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
359 /* If not RST, send dup ack */
362 tcp_program_dupack (tc0);
363 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
371 /* 2nd: check the RST bit */
372 if (PREDICT_FALSE (tcp_rst (th0)))
374 tcp_rcv_rst (wrk, tc0);
375 *error0 = TCP_ERROR_RST_RCVD;
379 /* 3rd: check security and precedence (skip) */
381 /* 4th: check the SYN bit (in window) */
382 if (PREDICT_FALSE (tcp_syn (th0)))
384 /* As per RFC5961 send challenge ack instead of reset */
385 tcp_program_ack (tc0);
386 *error0 = TCP_ERROR_SPURIOUS_SYN;
390 /* If segment in window, save timestamp */
391 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
392 vnet_buffer (b0)->tcp.seq_end);
400 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
402 /* SND.UNA =< SEG.ACK =< SND.NXT */
403 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
404 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
406 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
407 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
409 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
412 *error = TCP_ERROR_ACK_INVALID;
417 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
418 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
419 *error = TCP_ERROR_ACK_OK;
424 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
426 * Note that although the original article, srtt and rttvar are scaled
427 * to minimize round-off errors, here we don't. Instead, we rely on
428 * better precision time measurements.
431 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
437 err = mrtt - tc->srtt;
439 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
440 * The increase should be bound */
441 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
442 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
443 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
447 /* First measurement. */
449 tc->rttvar = mrtt >> 1;
454 tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
456 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
460 * Update rtt estimate
462 * We have potentially three sources of rtt measurements:
464 * TSOPT difference between current and echoed timestamp. It has ms
465 * precision and can be computed per ack
466 * ACK timing one sequence number is tracked per rtt with us (micro second)
468 * rate sample if enabled, all outstanding bytes are tracked with us
469 * precision. Every ack and sack are a rtt sample
471 * Middle boxes are known to fiddle with TCP options so we give higher
472 * priority to ACK timing.
474 * For now, rate sample rtts are only used under congestion.
477 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
481 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
482 * RTT because they're ambiguous. */
483 if (tcp_in_cong_recovery (tc))
485 /* Accept rtt estimates for samples that have not been retransmitted */
486 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
487 || (rs->flags & TCP_BTS_IS_RXT))
490 tcp_estimate_rtt_us (tc, rs->rtt_time);
491 mrtt = rs->rtt_time * THZ;
495 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
497 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
498 tcp_estimate_rtt_us (tc, sample);
499 mrtt = clib_max ((u32) (sample * THZ), 1);
500 /* Allow measuring of a new RTT */
503 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
504 * snd_una, i.e., the left side of the send window:
505 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
506 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
508 u32 now = tcp_tstamp (tc);
509 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
514 /* Ignore dubious measurements */
515 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
518 tcp_estimate_rtt (tc, mrtt);
522 /* If we got here something must've been ACKed so make sure boff is 0,
523 * even if mrtt is not valid since we update the rto lower */
531 tcp_estimate_initial_rtt (tcp_connection_t * tc)
533 u8 thread_index = vlib_num_workers ()? 1 : 0;
538 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
539 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
540 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
545 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
546 mrtt = clib_max (mrtt, 1);
547 /* Due to retransmits we don't know the initial mrtt */
548 if (tc->rto_boff && mrtt > 1 * THZ)
550 tc->mrtt_us = (f64) mrtt *TCP_TICK;
553 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
554 tcp_estimate_rtt (tc, mrtt);
559 * Dequeue bytes for connections that have received acks in last burst
562 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
564 u32 thread_index = wrk->vm->thread_index;
565 u32 *pending_deq_acked;
566 tcp_connection_t *tc;
569 if (!vec_len (wrk->pending_deq_acked))
572 pending_deq_acked = wrk->pending_deq_acked;
573 for (i = 0; i < vec_len (pending_deq_acked); i++)
575 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
576 tc->flags &= ~TCP_CONN_DEQ_PENDING;
578 if (PREDICT_FALSE (!tc->burst_acked))
581 /* Dequeue the newly ACKed bytes */
582 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
583 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
585 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
587 if (seq_leq (tc->psh_seq, tc->snd_una))
588 tc->flags &= ~TCP_CONN_PSH_PENDING;
591 if (tcp_is_descheduled (tc))
594 /* If everything has been acked, stop retransmit timer
595 * otherwise update. */
596 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
598 /* Update pacer based on our new cwnd estimate */
599 tcp_connection_tx_pacer_update (tc);
603 _vec_len (wrk->pending_deq_acked) = 0;
607 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
609 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
611 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
612 tc->flags |= TCP_CONN_DEQ_PENDING;
614 tc->burst_acked += tc->bytes_acked;
618 * Try to update snd_wnd based on feedback received from peer.
620 * If successful, and new window is 'effectively' 0, activate persist
624 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
626 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
627 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
628 if (seq_lt (tc->snd_wl1, seq)
629 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
631 tc->snd_wnd = snd_wnd;
634 TCP_EVT (TCP_EVT_SND_WND, tc);
636 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
638 /* Set persist timer if not set and we just got 0 wnd */
639 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
640 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
642 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
643 tcp_persist_timer_set (&wrk->timer_wheel, tc);
648 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
650 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
651 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
654 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
657 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
667 * Init loss recovery/fast recovery.
669 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
670 * updated in @ref tcp_cc_handle_event after fast retransmit
673 tcp_cc_init_congestion (tcp_connection_t * tc)
675 tcp_fastrecovery_on (tc);
676 tc->snd_congestion = tc->snd_nxt;
677 tc->cwnd_acc_bytes = 0;
678 tc->snd_rxt_bytes = 0;
679 tc->rxt_delivered = 0;
680 tc->prr_delivered = 0;
681 tc->prr_start = tc->snd_una;
682 tc->prev_ssthresh = tc->ssthresh;
683 tc->prev_cwnd = tc->cwnd;
685 tc->snd_rxt_ts = tcp_tstamp (tc);
686 tcp_cc_congestion (tc);
688 /* Post retransmit update cwnd to ssthresh and account for the
689 * three segments that have left the network and should've been
690 * buffered at the receiver XXX */
691 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
692 tc->cwnd += 3 * tc->snd_mss;
694 tc->fr_occurences += 1;
695 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
699 tcp_cc_congestion_undo (tcp_connection_t * tc)
701 tc->cwnd = tc->prev_cwnd;
702 tc->ssthresh = tc->prev_ssthresh;
703 tcp_cc_undo_recovery (tc);
704 ASSERT (tc->rto_boff == 0);
705 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
709 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
711 return (tcp_in_recovery (tc) && tc->rto_boff == 1
713 && tcp_opts_tstamp (&tc->rcv_opts)
714 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
718 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
720 return (tcp_cc_is_spurious_timeout_rxt (tc));
724 tcp_should_fastrecover_sack (tcp_connection_t * tc)
726 return (tc->sack_sb.lost_bytes
727 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
728 < tc->sack_sb.sacked_bytes));
732 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
736 /* If of of the two conditions lower hold, reset dupacks because
737 * we're probably after timeout (RFC6582 heuristics).
738 * If Cumulative ack does not cover more than congestion threshold,
740 * 1) The following doesn't hold: The congestion window is greater
741 * than SMSS bytes and the difference between highest_ack
742 * and prev_highest_ack is at most 4*SMSS bytes
743 * 2) Echoed timestamp in the last non-dup ack does not equal the
746 if (seq_leq (tc->snd_una, tc->snd_congestion)
747 && ((!(tc->cwnd > tc->snd_mss
748 && tc->bytes_acked <= 4 * tc->snd_mss))
749 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
755 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
756 || tcp_should_fastrecover_sack (tc));
760 tcp_cc_recover (tcp_connection_t * tc)
762 sack_scoreboard_hole_t *hole;
765 ASSERT (tcp_in_cong_recovery (tc));
767 if (tcp_cc_is_spurious_retransmit (tc))
769 tcp_cc_congestion_undo (tc);
773 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
776 /* Previous recovery left us congested. Continue sending as part
777 * of the current recovery event with an updated snd_congestion */
778 if (tc->sack_sb.sacked_bytes)
780 tc->snd_congestion = tc->snd_nxt;
781 tcp_program_retransmit (tc);
785 tc->rxt_delivered = 0;
786 tc->snd_rxt_bytes = 0;
788 tc->prr_delivered = 0;
790 tc->flags &= ~TCP_CONN_RXT_PENDING;
792 hole = scoreboard_first_hole (&tc->sack_sb);
793 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
794 scoreboard_clear (&tc->sack_sb);
796 if (!tcp_in_recovery (tc) && !is_spurious)
797 tcp_cc_recovered (tc);
799 tcp_fastrecovery_off (tc);
800 tcp_fastrecovery_first_off (tc);
801 tcp_recovery_off (tc);
802 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
804 ASSERT (tc->rto_boff == 0);
805 ASSERT (!tcp_in_cong_recovery (tc));
806 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
812 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
814 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
816 /* Congestion avoidance */
817 tcp_cc_rcv_ack (tc, rs);
819 /* If a cumulative ack, make sure dupacks is 0 */
822 /* When dupacks hits the threshold we only enter fast retransmit if
823 * cumulative ack covers more than snd_congestion. Should snd_una
824 * wrap this test may fail under otherwise valid circumstances.
825 * Therefore, proactively update snd_congestion when wrap detected. */
827 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
828 && seq_gt (tc->snd_congestion, tc->snd_una)))
829 tc->snd_congestion = tc->snd_una - 1;
833 * One function to rule them all ... and in the darkness bind them
836 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
839 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
841 /* If reneging, wait for timer based retransmits */
842 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
846 * If not in recovery, figure out if we should enter
848 if (!tcp_in_cong_recovery (tc))
853 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
854 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
856 if (tcp_should_fastrecover (tc, has_sack))
858 tcp_cc_init_congestion (tc);
861 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
863 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
864 tcp_program_retransmit (tc);
871 * Already in recovery
875 * Process (re)transmit feedback. Output path uses this to decide how much
876 * more data to release into the network
880 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
881 tcp_fastrecovery_first_on (tc);
883 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
884 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
885 - tc->sack_sb.last_bytes_delivered;
891 tc->rcv_dupacks += 1;
892 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
894 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
897 tc->prr_delivered += clib_min (tc->snd_mss,
898 tc->snd_nxt - tc->snd_una);
900 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
904 /* If partial ack, assume that the first un-acked segment was lost */
905 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
906 tcp_fastrecovery_first_on (tc);
910 * See if we can exit and stop retransmitting
912 if (seq_geq (tc->snd_una, tc->snd_congestion))
914 /* If spurious return, we've already updated everything */
915 if (tcp_cc_recover (tc))
917 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
921 /* Treat as congestion avoidance ack */
922 tcp_cc_rcv_ack (tc, rs);
926 tcp_program_retransmit (tc);
929 * Notify cc of the event
932 if (!tc->bytes_acked)
934 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
938 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
939 * reset dupacks to 0. Also needed if in congestion recovery */
942 if (tcp_in_recovery (tc))
943 tcp_cc_rcv_ack (tc, rs);
945 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
949 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
951 if (!tcp_in_cong_recovery (tc))
954 if (tcp_opts_sack_permitted (&tc->rcv_opts))
955 tcp_rcv_sacks (tc, tc->snd_una);
959 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
960 tcp_bt_sample_delivery_rate (tc, rs);
962 tcp_cc_handle_event (tc, rs, 1);
966 * Check if duplicate ack as per RFC5681 Sec. 2
969 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
972 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
973 && seq_gt (tc->snd_nxt, tc->snd_una)
974 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
975 && (prev_snd_wnd == tc->snd_wnd));
979 * Checks if ack is a congestion control event.
982 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
983 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
985 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
986 * defined to be 'duplicate' as well */
987 *is_dack = tc->sack_sb.last_sacked_bytes
988 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
990 return (*is_dack || tcp_in_cong_recovery (tc));
994 * Process incoming ACK
997 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
998 tcp_header_t * th, u32 * error)
1000 u32 prev_snd_wnd, prev_snd_una;
1001 tcp_rate_sample_t rs = { 0 };
1004 TCP_EVT (TCP_EVT_CC_STAT, tc);
1006 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1007 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1009 /* We've probably entered recovery and the peer still has some
1010 * of the data we've sent. Update snd_nxt and accept the ack */
1011 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1012 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1014 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1018 tc->errors.above_ack_wnd += 1;
1019 *error = TCP_ERROR_ACK_FUTURE;
1020 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1024 /* If old ACK, probably it's an old dupack */
1025 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1027 tc->errors.below_ack_wnd += 1;
1028 *error = TCP_ERROR_ACK_OLD;
1029 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1031 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1034 tcp_handle_old_ack (tc, &rs);
1036 /* Don't drop yet */
1043 * Looks okay, process feedback
1046 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1047 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1049 prev_snd_wnd = tc->snd_wnd;
1050 prev_snd_una = tc->snd_una;
1051 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1052 vnet_buffer (b)->tcp.ack_number,
1053 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1054 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1055 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1056 tcp_validate_txf_size (tc, tc->bytes_acked);
1058 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1059 tcp_bt_sample_delivery_rate (tc, &rs);
1061 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1063 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1064 if (tc->bytes_acked)
1065 tcp_program_dequeue (wrk, tc);
1068 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1071 * Check if we have congestion event
1074 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1076 tcp_cc_handle_event (tc, &rs, is_dack);
1077 tc->dupacks_in += is_dack;
1078 if (!tcp_in_cong_recovery (tc))
1080 *error = TCP_ERROR_ACK_OK;
1083 *error = TCP_ERROR_ACK_DUP;
1084 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1090 * Update congestion control (slow start/congestion avoidance)
1092 tcp_cc_update (tc, &rs);
1093 *error = TCP_ERROR_ACK_OK;
1098 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1100 if (!tcp_disconnect_pending (tc))
1102 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1103 tcp_disconnect_pending_on (tc);
1108 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1110 u32 thread_index, *pending_disconnects, *pending_resets;
1111 tcp_connection_t *tc;
1114 if (vec_len (wrk->pending_disconnects))
1116 thread_index = wrk->vm->thread_index;
1117 pending_disconnects = wrk->pending_disconnects;
1118 for (i = 0; i < vec_len (pending_disconnects); i++)
1120 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1121 tcp_disconnect_pending_off (tc);
1122 session_transport_closing_notify (&tc->connection);
1124 _vec_len (wrk->pending_disconnects) = 0;
1127 if (vec_len (wrk->pending_resets))
1129 thread_index = wrk->vm->thread_index;
1130 pending_resets = wrk->pending_resets;
1131 for (i = 0; i < vec_len (pending_resets); i++)
1133 tc = tcp_connection_get (pending_resets[i], thread_index);
1134 tcp_disconnect_pending_off (tc);
1135 tcp_handle_rst (tc);
1137 _vec_len (wrk->pending_resets) = 0;
1142 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1145 /* Reject out-of-order fins */
1146 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1149 /* Account for the FIN and send ack */
1151 tc->flags |= TCP_CONN_FINRCVD;
1152 tcp_program_ack (tc);
1153 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1154 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1155 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1156 tcp_program_disconnect (wrk, tc);
1157 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1158 tcp_cfg.closewait_time);
1159 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1160 *error = TCP_ERROR_FIN_RCVD;
1163 /** Enqueue data for delivery to application */
1165 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1168 int written, error = TCP_ERROR_ENQUEUED;
1170 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1172 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1173 1 /* queue event */ , 1);
1174 tc->bytes_in += written;
1176 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1178 /* Update rcv_nxt */
1179 if (PREDICT_TRUE (written == data_len))
1181 tc->rcv_nxt += written;
1183 /* If more data written than expected, account for out-of-order bytes. */
1184 else if (written > data_len)
1186 tc->rcv_nxt += written;
1187 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1189 else if (written > 0)
1191 /* We've written something but FIFO is probably full now */
1192 tc->rcv_nxt += written;
1193 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1197 /* Packet made it through for ack processing */
1198 if (tc->rcv_wnd < tc->snd_mss)
1199 return TCP_ERROR_ZERO_RWND;
1201 return TCP_ERROR_FIFO_FULL;
1204 /* Update SACK list if need be */
1205 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1207 /* Remove SACK blocks that have been delivered */
1208 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1214 /** Enqueue out-of-order data */
1216 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1222 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1225 /* Enqueue out-of-order data with relative offset */
1226 rv = session_enqueue_stream_connection (&tc->connection, b,
1227 vnet_buffer (b)->tcp.seq_number -
1228 tc->rcv_nxt, 0 /* queue event */ ,
1231 /* Nothing written */
1234 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1235 return TCP_ERROR_FIFO_FULL;
1238 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1239 tc->bytes_in += data_len;
1241 /* Update SACK list if in use */
1242 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1244 ooo_segment_t *newest;
1247 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1249 /* Get the newest segment from the fifo */
1250 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1253 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1254 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1255 start = tc->rcv_nxt + offset;
1256 end = start + ooo_segment_length (s0->rx_fifo, newest);
1257 tcp_update_sack_list (tc, start, end);
1258 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1259 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1263 return TCP_ERROR_ENQUEUED_OOO;
1267 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1269 u32 discard, first = b->current_length;
1270 vlib_main_t *vm = vlib_get_main ();
1272 /* Handle multi-buffer segments */
1273 if (n_bytes_to_drop > b->current_length)
1275 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1279 discard = clib_min (n_bytes_to_drop, b->current_length);
1280 vlib_buffer_advance (b, discard);
1281 b = vlib_get_buffer (vm, b->next_buffer);
1282 n_bytes_to_drop -= discard;
1284 while (n_bytes_to_drop);
1285 if (n_bytes_to_drop > first)
1286 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1289 vlib_buffer_advance (b, n_bytes_to_drop);
1290 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1295 * Receive buffer for connection and handle acks
1297 * It handles both in order or out-of-order data.
1300 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1303 u32 error, n_bytes_to_drop, n_data_bytes;
1305 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1306 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1307 ASSERT (n_data_bytes);
1308 tc->data_segs_in += 1;
1310 /* Handle out-of-order data */
1311 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1313 /* Old sequence numbers allowed through because they overlapped
1315 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1317 /* Completely in the past (possible retransmit). Ack
1318 * retransmissions since we may not have any data to send */
1319 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1321 tcp_program_dupack (tc);
1322 tc->errors.below_data_wnd++;
1323 error = TCP_ERROR_SEGMENT_OLD;
1327 /* Chop off the bytes in the past and see if what is left
1328 * can be enqueued in order */
1329 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1330 n_data_bytes -= n_bytes_to_drop;
1331 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1332 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1334 error = TCP_ERROR_SEGMENT_OLD;
1340 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1341 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1342 tcp_program_dupack (tc);
1343 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1344 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1345 tc->rcv_las + tc->rcv_wnd);
1351 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1352 * segments can be enqueued after fifo tail offset changes. */
1353 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1354 tcp_program_ack (tc);
1362 tcp_header_t tcp_header;
1363 tcp_connection_t tcp_connection;
1367 format_tcp_rx_trace (u8 * s, va_list * args)
1369 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1370 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1371 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1372 tcp_connection_t *tc = &t->tcp_connection;
1373 u32 indent = format_get_indent (s);
1375 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1376 format_tcp_state, tc->state, format_white_space, indent,
1377 format_tcp_header, &t->tcp_header, 128);
1383 format_tcp_rx_trace_short (u8 * s, va_list * args)
1385 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1386 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1387 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1389 s = format (s, "%d -> %d (%U)",
1390 clib_net_to_host_u16 (t->tcp_header.dst_port),
1391 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1392 t->tcp_connection.state);
1398 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1399 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1403 clib_memcpy_fast (&t0->tcp_connection, tc0,
1404 sizeof (t0->tcp_connection));
1408 th0 = tcp_buffer_hdr (b0);
1410 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1414 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1415 vlib_frame_t * frame, u8 is_ip4)
1419 n_left = frame->n_vectors;
1420 from = vlib_frame_vector_args (frame);
1424 tcp_connection_t *tc0;
1431 b0 = vlib_get_buffer (vm, bi0);
1433 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1435 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1436 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1438 th0 = tcp_buffer_hdr (b0);
1439 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1448 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1449 u8 is_ip4, u32 evt, u32 val)
1452 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1454 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1457 #define tcp_maybe_inc_counter(node_id, err, count) \
1459 if (next0 != tcp_next_drop (is_ip4)) \
1460 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1461 tcp6_##node_id##_node.index, is_ip4, err, \
1464 #define tcp_inc_counter(node_id, err, count) \
1465 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1466 tcp6_##node_id##_node.index, is_ip4, \
1468 #define tcp_maybe_inc_err_counter(cnts, err) \
1470 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1472 #define tcp_inc_err_counter(cnts, err, val) \
1476 #define tcp_store_err_counters(node_id, cnts) \
1479 for (i = 0; i < TCP_N_ERROR; i++) \
1481 tcp_inc_counter(node_id, i, cnts[i]); \
1486 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1487 vlib_frame_t * frame, int is_ip4)
1489 u32 thread_index = vm->thread_index, errors = 0;
1490 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1491 u32 n_left_from, *from, *first_buffer;
1492 u16 err_counters[TCP_N_ERROR] = { 0 };
1494 if (node->flags & VLIB_NODE_FLAG_TRACE)
1495 tcp_established_trace_frame (vm, node, frame, is_ip4);
1497 first_buffer = from = vlib_frame_vector_args (frame);
1498 n_left_from = frame->n_vectors;
1500 while (n_left_from > 0)
1502 u32 bi0, error0 = TCP_ERROR_ACK_OK;
1505 tcp_connection_t *tc0;
1507 if (n_left_from > 1)
1510 pb = vlib_get_buffer (vm, from[1]);
1511 vlib_prefetch_buffer_header (pb, LOAD);
1512 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1519 b0 = vlib_get_buffer (vm, bi0);
1520 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1523 if (PREDICT_FALSE (tc0 == 0))
1525 error0 = TCP_ERROR_INVALID_CONNECTION;
1529 th0 = tcp_buffer_hdr (b0);
1531 /* TODO header prediction fast path */
1533 /* 1-4: check SEQ, RST, SYN */
1534 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
1536 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
1540 /* 5: check the ACK field */
1541 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
1544 /* 6: check the URG bit TODO */
1546 /* 7: process the segment text */
1547 if (vnet_buffer (b0)->tcp.data_len)
1548 error0 = tcp_segment_rcv (wrk, tc0, b0);
1550 /* 8: check the FIN bit */
1551 if (PREDICT_FALSE (tcp_is_fin (th0)))
1552 tcp_rcv_fin (wrk, tc0, b0, &error0);
1555 tcp_inc_err_counter (err_counters, error0, 1);
1558 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1560 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1561 tcp_store_err_counters (established, err_counters);
1562 tcp_handle_postponed_dequeues (wrk);
1563 tcp_handle_disconnects (wrk);
1564 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
1566 return frame->n_vectors;
1569 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1570 vlib_node_runtime_t * node,
1571 vlib_frame_t * from_frame)
1573 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1576 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1577 vlib_node_runtime_t * node,
1578 vlib_frame_t * from_frame)
1580 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1584 VLIB_REGISTER_NODE (tcp4_established_node) =
1586 .name = "tcp4-established",
1587 /* Takes a vector of packets. */
1588 .vector_size = sizeof (u32),
1589 .n_errors = TCP_N_ERROR,
1590 .error_strings = tcp_error_strings,
1591 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1594 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1595 foreach_tcp_state_next
1598 .format_trace = format_tcp_rx_trace_short,
1603 VLIB_REGISTER_NODE (tcp6_established_node) =
1605 .name = "tcp6-established",
1606 /* Takes a vector of packets. */
1607 .vector_size = sizeof (u32),
1608 .n_errors = TCP_N_ERROR,
1609 .error_strings = tcp_error_strings,
1610 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1613 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1614 foreach_tcp_state_next
1617 .format_trace = format_tcp_rx_trace_short,
1623 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1626 transport_connection_t *tmp = 0;
1633 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1636 u8 is_ip_valid = 0, val_l, val_r;
1638 if (tc->connection.is_ip4)
1640 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1642 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1643 &tc->connection.lcl_ip.ip4);
1644 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1645 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1646 &tc->connection.rmt_ip.ip4);
1647 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1648 is_ip_valid = val_l && val_r;
1652 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1654 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1655 &tc->connection.lcl_ip.ip6);
1656 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1657 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1658 &tc->connection.rmt_ip.ip6);
1659 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1660 is_ip_valid = val_l && val_r;
1663 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1664 && (tc->state == TCP_STATE_LISTEN
1665 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1669 handle = session_lookup_half_open_handle (&tc->connection);
1670 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1671 tc->c_proto, tc->c_is_ip4);
1675 if (tmp->lcl_port == hdr->dst_port
1676 && tmp->rmt_port == hdr->src_port)
1678 TCP_DBG ("half-open is valid!");
1687 * Lookup transport connection
1689 static tcp_connection_t *
1690 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1694 transport_connection_t *tconn;
1695 tcp_connection_t *tc;
1700 ip4 = vlib_buffer_get_current (b);
1701 tcp = ip4_next_header (ip4);
1702 tconn = session_lookup_connection_wt4 (fib_index,
1707 TRANSPORT_PROTO_TCP,
1708 thread_index, &is_filtered);
1709 tc = tcp_get_connection_from_transport (tconn);
1710 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1715 ip6 = vlib_buffer_get_current (b);
1716 tcp = ip6_next_header (ip6);
1717 tconn = session_lookup_connection_wt6 (fib_index,
1722 TRANSPORT_PROTO_TCP,
1723 thread_index, &is_filtered);
1724 tc = tcp_get_connection_from_transport (tconn);
1725 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1730 static tcp_connection_t *
1731 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1737 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1738 tcp_header_t *tcp = tcp_buffer_hdr (b);
1739 s = session_lookup_listener4 (fib_index,
1741 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1745 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1746 tcp_header_t *tcp = tcp_buffer_hdr (b);
1747 s = session_lookup_listener6 (fib_index,
1749 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1752 if (PREDICT_TRUE (s != 0))
1753 return tcp_get_connection_from_transport (transport_get_listener
1754 (TRANSPORT_PROTO_TCP,
1755 s->connection_index));
1761 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1763 vnet_main_t *vnm = vnet_get_main ();
1764 const dpo_id_t *dpo;
1765 const load_balance_t *lb;
1766 vnet_hw_interface_t *hw_if;
1767 u32 sw_if_idx, lb_idx;
1771 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1772 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1776 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1777 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1780 lb = load_balance_get (lb_idx);
1781 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1783 dpo = load_balance_get_bucket_i (lb, 0);
1785 sw_if_idx = dpo_get_urpf (dpo);
1786 if (PREDICT_FALSE (sw_if_idx == ~0))
1789 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1790 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
1791 tc->cfg_flags |= TCP_CFG_F_TSO;
1795 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1796 vlib_frame_t * from_frame, int is_ip4)
1798 u32 n_left_from, *from, *first_buffer, errors = 0;
1799 u32 my_thread_index = vm->thread_index;
1800 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
1802 from = first_buffer = vlib_frame_vector_args (from_frame);
1803 n_left_from = from_frame->n_vectors;
1805 while (n_left_from > 0)
1807 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
1808 tcp_connection_t *tc0, *new_tc0;
1809 tcp_header_t *tcp0 = 0;
1817 b0 = vlib_get_buffer (vm, bi0);
1819 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
1820 if (PREDICT_FALSE (tc0 == 0))
1822 error0 = TCP_ERROR_INVALID_CONNECTION;
1826 /* Half-open completed recently but the connection was't removed
1827 * yet by the owning thread */
1828 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1830 /* Make sure the connection actually exists */
1831 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
1832 my_thread_index, is_ip4));
1833 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
1837 ack0 = vnet_buffer (b0)->tcp.ack_number;
1838 seq0 = vnet_buffer (b0)->tcp.seq_number;
1839 tcp0 = tcp_buffer_hdr (b0);
1841 /* Crude check to see if the connection handle does not match
1842 * the packet. Probably connection just switched to established */
1843 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1844 || tcp0->src_port != tc0->c_rmt_port))
1846 error0 = TCP_ERROR_INVALID_CONNECTION;
1850 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
1851 && !tcp_syn (tcp0)))
1853 error0 = TCP_ERROR_SEGMENT_INVALID;
1857 /* SYNs consume sequence numbers */
1858 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
1861 * 1. check the ACK bit
1865 * If the ACK bit is set
1866 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1867 * the RST bit is set, if so drop the segment and return)
1868 * <SEQ=SEG.ACK><CTL=RST>
1869 * and discard the segment. Return.
1870 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1874 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
1876 if (!tcp_rst (tcp0))
1877 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1878 error0 = TCP_ERROR_RCV_WND;
1882 /* Make sure ACK is valid */
1883 if (seq_gt (tc0->snd_una, ack0))
1885 error0 = TCP_ERROR_ACK_INVALID;
1891 * 2. check the RST bit
1896 /* If ACK is acceptable, signal client that peer is not
1897 * willing to accept connection and drop connection*/
1899 tcp_rcv_rst (wrk, tc0);
1900 error0 = TCP_ERROR_RST_RCVD;
1905 * 3. check the security and precedence (skipped)
1909 * 4. check the SYN bit
1912 /* No SYN flag. Drop. */
1913 if (!tcp_syn (tcp0))
1915 error0 = TCP_ERROR_SEGMENT_INVALID;
1920 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
1922 error0 = TCP_ERROR_OPTIONS;
1926 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1927 * current thread pool. */
1928 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
1929 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
1930 new_tc0->irs = seq0;
1931 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1932 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1934 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
1936 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
1937 new_tc0->tsval_recent_age = tcp_time_now ();
1940 if (tcp_opts_wscale (&new_tc0->rcv_opts))
1941 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
1943 new_tc0->rcv_wscale = 0;
1945 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
1946 << new_tc0->snd_wscale;
1947 new_tc0->snd_wl1 = seq0;
1948 new_tc0->snd_wl2 = ack0;
1950 tcp_connection_init_vars (new_tc0);
1952 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1953 if (PREDICT_TRUE (tcp_ack (tcp0)))
1955 /* Our SYN is ACKed: we have iss < ack = snd_una */
1957 /* TODO Dequeue acknowledged segments if we support Fast Open */
1958 new_tc0->snd_una = ack0;
1959 new_tc0->state = TCP_STATE_ESTABLISHED;
1961 /* Make sure las is initialized for the wnd computation */
1962 new_tc0->rcv_las = new_tc0->rcv_nxt;
1964 /* Notify app that we have connection. If session layer can't
1965 * allocate session send reset */
1966 if (session_stream_connect_notify (&new_tc0->connection,
1969 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
1970 tcp_connection_cleanup (new_tc0);
1971 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1975 new_tc0->tx_fifo_size =
1976 transport_tx_fifo_size (&new_tc0->connection);
1977 /* Update rtt with the syn-ack sample */
1978 tcp_estimate_initial_rtt (new_tc0);
1979 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
1980 error0 = TCP_ERROR_SYN_ACKS_RCVD;
1982 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1985 new_tc0->state = TCP_STATE_SYN_RCVD;
1987 /* Notify app that we have connection */
1988 if (session_stream_connect_notify (&new_tc0->connection,
1991 tcp_connection_cleanup (new_tc0);
1992 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1993 TCP_EVT (TCP_EVT_RST_SENT, tc0);
1994 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1998 new_tc0->tx_fifo_size =
1999 transport_tx_fifo_size (&new_tc0->connection);
2000 new_tc0->rtt_ts = 0;
2001 tcp_init_snd_vars (new_tc0);
2002 tcp_send_synack (new_tc0);
2003 error0 = TCP_ERROR_SYNS_RCVD;
2007 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2008 tcp_check_tx_offload (new_tc0, is_ip4);
2010 /* Read data, if any */
2011 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2013 clib_warning ("rcvd data in syn-sent");
2014 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2015 if (error0 == TCP_ERROR_ACK_OK)
2016 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2020 /* Send ack now instead of programming it because connection was
2021 * just established and it's not optional. */
2022 tcp_send_ack (new_tc0);
2027 /* If this is not the owning thread, wait for syn retransmit to
2028 * expire and cleanup then */
2029 if (tcp_half_open_connection_cleanup (tc0))
2030 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2034 tcp_inc_counter (syn_sent, error0, 1);
2035 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2037 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2038 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2039 clib_memcpy_fast (&t0->tcp_connection, tc0,
2040 sizeof (t0->tcp_connection));
2044 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2046 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2047 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2048 tcp_handle_disconnects (wrk);
2050 return from_frame->n_vectors;
2053 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2054 vlib_node_runtime_t * node,
2055 vlib_frame_t * from_frame)
2057 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2060 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2061 vlib_node_runtime_t * node,
2062 vlib_frame_t * from_frame)
2064 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2068 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2070 .name = "tcp4-syn-sent",
2071 /* Takes a vector of packets. */
2072 .vector_size = sizeof (u32),
2073 .n_errors = TCP_N_ERROR,
2074 .error_strings = tcp_error_strings,
2075 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2078 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2079 foreach_tcp_state_next
2082 .format_trace = format_tcp_rx_trace_short,
2087 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2089 .name = "tcp6-syn-sent",
2090 /* Takes a vector of packets. */
2091 .vector_size = sizeof (u32),
2092 .n_errors = TCP_N_ERROR,
2093 .error_strings = tcp_error_strings,
2094 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2097 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2098 foreach_tcp_state_next
2101 .format_trace = format_tcp_rx_trace_short,
2106 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2107 * as per RFC793 p. 64
2110 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2111 vlib_frame_t * from_frame, int is_ip4)
2113 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2114 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2115 u32 n_left_from, *from, max_dequeue;
2117 from = first_buffer = vlib_frame_vector_args (from_frame);
2118 n_left_from = from_frame->n_vectors;
2120 while (n_left_from > 0)
2122 u32 bi0, error0 = TCP_ERROR_NONE;
2123 tcp_header_t *tcp0 = 0;
2124 tcp_connection_t *tc0;
2132 b0 = vlib_get_buffer (vm, bi0);
2133 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2135 if (PREDICT_FALSE (tc0 == 0))
2137 error0 = TCP_ERROR_INVALID_CONNECTION;
2141 tcp0 = tcp_buffer_hdr (b0);
2142 is_fin0 = tcp_is_fin (tcp0);
2146 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2148 tcp_connection_t *tmp;
2149 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2151 if (tmp->state != tc0->state)
2153 if (tc0->state != TCP_STATE_CLOSED)
2154 clib_warning ("state changed");
2161 * Special treatment for CLOSED
2163 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2165 error0 = TCP_ERROR_CONNECTION_CLOSED;
2170 * For all other states (except LISTEN)
2173 /* 1-4: check SEQ, RST, SYN */
2174 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2177 /* 5: check the ACK field */
2180 case TCP_STATE_SYN_RCVD:
2182 /* Make sure the segment is exactly right */
2183 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2185 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2186 error0 = TCP_ERROR_SEGMENT_INVALID;
2191 * If the segment acknowledgment is not acceptable, form a
2193 * <SEQ=SEG.ACK><CTL=RST>
2196 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2198 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2199 error0 = TCP_ERROR_SEGMENT_INVALID;
2203 /* Update rtt and rto */
2204 tcp_estimate_initial_rtt (tc0);
2205 tcp_connection_tx_pacer_update (tc0);
2207 /* Switch state to ESTABLISHED */
2208 tc0->state = TCP_STATE_ESTABLISHED;
2209 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2211 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2212 tcp_check_tx_offload (tc0, is_ip4);
2214 /* Initialize session variables */
2215 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2216 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2217 << tc0->rcv_opts.wscale;
2218 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2219 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2221 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2222 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc0);
2223 if (session_stream_accept_notify (&tc0->connection))
2225 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2226 tcp_send_reset (tc0);
2227 session_transport_delete_notify (&tc0->connection);
2228 tcp_connection_cleanup (tc0);
2231 error0 = TCP_ERROR_ACK_OK;
2233 case TCP_STATE_ESTABLISHED:
2234 /* We can get packets in established state here because they
2235 * were enqueued before state change */
2236 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2240 case TCP_STATE_FIN_WAIT_1:
2241 /* In addition to the processing for the ESTABLISHED state, if
2242 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2243 * continue processing in that state. */
2244 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2247 /* Still have to send the FIN */
2248 if (tc0->flags & TCP_CONN_FINPNDG)
2250 /* TX fifo finally drained */
2251 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2252 if (max_dequeue <= tc0->burst_acked)
2254 /* If a fin was received and data was acked extend wait */
2255 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2256 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2257 tcp_cfg.closewait_time);
2259 /* If FIN is ACKed */
2260 else if (tc0->snd_una == tc0->snd_nxt)
2262 /* Stop all retransmit timers because we have nothing more
2264 tcp_connection_timers_reset (tc0);
2266 /* We already have a FIN but didn't transition to CLOSING
2267 * because of outstanding tx data. Close the connection. */
2268 if (tc0->flags & TCP_CONN_FINRCVD)
2270 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2271 session_transport_closed_notify (&tc0->connection);
2272 tcp_program_cleanup (wrk, tc0);
2276 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2277 /* Enable waitclose because we're willing to wait for peer's
2278 * FIN but not indefinitely. */
2279 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2280 tcp_cfg.finwait2_time);
2282 /* Don't try to deq the FIN acked */
2283 if (tc0->burst_acked > 1)
2284 session_tx_fifo_dequeue_drop (&tc0->connection,
2285 tc0->burst_acked - 1);
2286 tc0->burst_acked = 0;
2289 case TCP_STATE_FIN_WAIT_2:
2290 /* In addition to the processing for the ESTABLISHED state, if
2291 * the retransmission queue is empty, the user's CLOSE can be
2292 * acknowledged ("ok") but do not delete the TCB. */
2293 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2295 tc0->burst_acked = 0;
2297 case TCP_STATE_CLOSE_WAIT:
2298 /* Do the same processing as for the ESTABLISHED state. */
2299 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2302 if (!(tc0->flags & TCP_CONN_FINPNDG))
2305 /* Still have outstanding tx data */
2306 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2307 if (max_dequeue > tc0->burst_acked)
2311 tcp_connection_timers_reset (tc0);
2312 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2313 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2314 tcp_cfg.lastack_time);
2316 case TCP_STATE_CLOSING:
2317 /* In addition to the processing for the ESTABLISHED state, if
2318 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2319 * otherwise ignore the segment. */
2320 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2323 if (tc0->snd_una != tc0->snd_nxt)
2326 tcp_connection_timers_reset (tc0);
2327 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2328 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2329 tcp_cfg.timewait_time);
2330 session_transport_closed_notify (&tc0->connection);
2334 case TCP_STATE_LAST_ACK:
2335 /* The only thing that [should] arrive in this state is an
2336 * acknowledgment of our FIN. If our FIN is now acknowledged,
2337 * delete the TCB, enter the CLOSED state, and return. */
2339 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2342 /* Apparently our ACK for the peer's FIN was lost */
2343 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2349 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2350 session_transport_closed_notify (&tc0->connection);
2352 /* Don't free the connection from the data path since
2353 * we can't ensure that we have no packets already enqueued
2354 * to output. Rely instead on the waitclose timer */
2355 tcp_connection_timers_reset (tc0);
2356 tcp_program_cleanup (tcp_get_worker (tc0->c_thread_index), tc0);
2361 case TCP_STATE_TIME_WAIT:
2362 /* The only thing that can arrive in this state is a
2363 * retransmission of the remote FIN. Acknowledge it, and restart
2364 * the 2 MSL timeout. */
2366 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2372 tcp_program_ack (tc0);
2373 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2374 tcp_cfg.timewait_time);
2382 /* 6: check the URG bit TODO */
2384 /* 7: process the segment text */
2387 case TCP_STATE_ESTABLISHED:
2388 case TCP_STATE_FIN_WAIT_1:
2389 case TCP_STATE_FIN_WAIT_2:
2390 if (vnet_buffer (b0)->tcp.data_len)
2391 error0 = tcp_segment_rcv (wrk, tc0, b0);
2393 case TCP_STATE_CLOSE_WAIT:
2394 case TCP_STATE_CLOSING:
2395 case TCP_STATE_LAST_ACK:
2396 case TCP_STATE_TIME_WAIT:
2397 /* This should not occur, since a FIN has been received from the
2398 * remote side. Ignore the segment text. */
2402 /* 8: check the FIN bit */
2406 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
2410 case TCP_STATE_ESTABLISHED:
2411 /* Account for the FIN and send ack */
2413 tcp_program_ack (tc0);
2414 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
2415 tcp_program_disconnect (wrk, tc0);
2416 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2417 tcp_cfg.closewait_time);
2419 case TCP_STATE_SYN_RCVD:
2420 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2421 * notified yet, set a cleanup timer instead of relying on
2422 * disconnect notify and the implicit close call. */
2423 tcp_connection_timers_reset (tc0);
2426 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2427 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2428 tcp_cfg.lastack_time);
2430 case TCP_STATE_CLOSE_WAIT:
2431 case TCP_STATE_CLOSING:
2432 case TCP_STATE_LAST_ACK:
2435 case TCP_STATE_FIN_WAIT_1:
2438 if (tc0->flags & TCP_CONN_FINPNDG)
2440 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2441 * sending it. Since we already received a fin, do not wait
2443 tc0->flags |= TCP_CONN_FINRCVD;
2444 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2445 tcp_cfg.closewait_time);
2449 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2450 tcp_program_ack (tc0);
2451 /* Wait for ACK for our FIN but not forever */
2452 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2453 tcp_cfg.closing_time);
2456 case TCP_STATE_FIN_WAIT_2:
2457 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2459 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2460 tcp_connection_timers_reset (tc0);
2461 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2462 tcp_cfg.timewait_time);
2463 tcp_program_ack (tc0);
2464 session_transport_closed_notify (&tc0->connection);
2466 case TCP_STATE_TIME_WAIT:
2467 /* Remain in the TIME-WAIT state. Restart the time-wait
2470 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2471 tcp_cfg.timewait_time);
2474 error0 = TCP_ERROR_FIN_RCVD;
2478 tcp_inc_counter (rcv_process, error0, 1);
2479 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2481 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2482 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2486 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2488 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2489 tcp_handle_postponed_dequeues (wrk);
2490 tcp_handle_disconnects (wrk);
2491 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2493 return from_frame->n_vectors;
2496 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2497 vlib_node_runtime_t * node,
2498 vlib_frame_t * from_frame)
2500 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2503 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2504 vlib_node_runtime_t * node,
2505 vlib_frame_t * from_frame)
2507 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2511 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2513 .name = "tcp4-rcv-process",
2514 /* Takes a vector of packets. */
2515 .vector_size = sizeof (u32),
2516 .n_errors = TCP_N_ERROR,
2517 .error_strings = tcp_error_strings,
2518 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2521 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2522 foreach_tcp_state_next
2525 .format_trace = format_tcp_rx_trace_short,
2530 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2532 .name = "tcp6-rcv-process",
2533 /* Takes a vector of packets. */
2534 .vector_size = sizeof (u32),
2535 .n_errors = TCP_N_ERROR,
2536 .error_strings = tcp_error_strings,
2537 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2540 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2541 foreach_tcp_state_next
2544 .format_trace = format_tcp_rx_trace_short,
2549 * LISTEN state processing as per RFC 793 p. 65
2552 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2553 vlib_frame_t * from_frame, int is_ip4)
2555 u32 n_left_from, *from, n_syns = 0, *first_buffer;
2556 u32 thread_index = vm->thread_index;
2558 from = first_buffer = vlib_frame_vector_args (from_frame);
2559 n_left_from = from_frame->n_vectors;
2561 while (n_left_from > 0)
2563 u32 bi, error = TCP_ERROR_NONE;
2564 tcp_connection_t *lc, *child;
2571 b = vlib_get_buffer (vm, bi);
2573 lc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2574 if (PREDICT_FALSE (lc == 0))
2576 tcp_connection_t *tc;
2577 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2579 if (tc->state != TCP_STATE_TIME_WAIT)
2581 error = TCP_ERROR_CREATE_EXISTS;
2584 lc = tcp_lookup_listener (b, tc->c_fib_index, is_ip4);
2585 /* clean up the old session */
2586 tcp_connection_del (tc);
2589 /* Make sure connection wasn't just created */
2590 child = tcp_lookup_connection (lc->c_fib_index, b, thread_index,
2592 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2594 error = TCP_ERROR_CREATE_EXISTS;
2598 /* Create child session. For syn-flood protection use filter */
2600 /* 1. first check for an RST: handled in dispatch */
2601 /* if (tcp_rst (th0))
2605 /* 2. second check for an ACK: handled in dispatch */
2606 /* if (tcp_ack (th0))
2608 tcp_send_reset (b0, is_ip4);
2613 /* 3. check for a SYN (did that already) */
2615 /* Create child session and send SYN-ACK */
2616 child = tcp_connection_alloc (thread_index);
2618 if (tcp_options_parse (tcp_buffer_hdr (b), &child->rcv_opts, 1))
2620 error = TCP_ERROR_OPTIONS;
2621 tcp_connection_free (child);
2625 tcp_init_w_buffer (child, b, is_ip4);
2627 child->state = TCP_STATE_SYN_RCVD;
2628 child->c_fib_index = lc->c_fib_index;
2629 child->cc_algo = lc->cc_algo;
2630 tcp_connection_init_vars (child);
2631 child->rto = TCP_RTO_MIN;
2634 * This initializes elog track, must be done before synack.
2635 * We also do it before possible tcp_connection_cleanup() as it
2636 * generates TCP_EVT_DELETE event.
2638 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2640 if (session_stream_accept (&child->connection, lc->c_s_index,
2641 lc->c_thread_index, 0 /* notify */ ))
2643 tcp_connection_cleanup (child);
2644 error = TCP_ERROR_CREATE_SESSION_FAIL;
2648 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2650 tcp_send_synack (child);
2654 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
2657 t = vlib_add_trace (vm, node, b, sizeof (*t));
2658 clib_memcpy_fast (&t->tcp_header, tcp_buffer_hdr (b),
2659 sizeof (t->tcp_header));
2660 clib_memcpy_fast (&t->tcp_connection, lc,
2661 sizeof (t->tcp_connection));
2664 n_syns += (error == TCP_ERROR_NONE);
2667 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2668 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2670 return from_frame->n_vectors;
2673 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2674 vlib_frame_t * from_frame)
2676 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2679 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2680 vlib_frame_t * from_frame)
2682 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2686 VLIB_REGISTER_NODE (tcp4_listen_node) =
2688 .name = "tcp4-listen",
2689 /* Takes a vector of packets. */
2690 .vector_size = sizeof (u32),
2691 .n_errors = TCP_N_ERROR,
2692 .error_strings = tcp_error_strings,
2693 .n_next_nodes = TCP_LISTEN_N_NEXT,
2696 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2697 foreach_tcp_state_next
2700 .format_trace = format_tcp_rx_trace_short,
2705 VLIB_REGISTER_NODE (tcp6_listen_node) =
2707 .name = "tcp6-listen",
2708 /* Takes a vector of packets. */
2709 .vector_size = sizeof (u32),
2710 .n_errors = TCP_N_ERROR,
2711 .error_strings = tcp_error_strings,
2712 .n_next_nodes = TCP_LISTEN_N_NEXT,
2715 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2716 foreach_tcp_state_next
2719 .format_trace = format_tcp_rx_trace_short,
2723 typedef enum _tcp_input_next
2725 TCP_INPUT_NEXT_DROP,
2726 TCP_INPUT_NEXT_LISTEN,
2727 TCP_INPUT_NEXT_RCV_PROCESS,
2728 TCP_INPUT_NEXT_SYN_SENT,
2729 TCP_INPUT_NEXT_ESTABLISHED,
2730 TCP_INPUT_NEXT_RESET,
2731 TCP_INPUT_NEXT_PUNT,
2735 #define foreach_tcp4_input_next \
2736 _ (DROP, "ip4-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, "ip6-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_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2757 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2759 tcp_connection_t *tc;
2764 for (i = 0; i < n_bufs; i++)
2766 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2768 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2769 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2771 tcp = vlib_buffer_get_current (bs[i]);
2772 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2778 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2780 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2782 *next = TCP_INPUT_NEXT_DROP;
2784 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2786 *next = TCP_INPUT_NEXT_PUNT;
2787 *error = TCP_ERROR_PUNT;
2791 *next = TCP_INPUT_NEXT_RESET;
2792 *error = TCP_ERROR_NO_LISTENER;
2797 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2798 vlib_buffer_t * b, u16 * next,
2799 vlib_node_runtime_t * error_node)
2805 tcp = tcp_buffer_hdr (b);
2806 flags = tcp->flags & filter_flags;
2807 *next = tm->dispatch_table[tc->state][flags].next;
2808 error = tm->dispatch_table[tc->state][flags].error;
2811 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2813 b->error = error_node->errors[error];
2814 if (error == TCP_ERROR_DISPATCH)
2815 clib_warning ("tcp conn %u disp error state %U flags %U",
2816 tc->c_c_index, format_tcp_state, tc->state,
2817 format_tcp_flags, (int) flags);
2822 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2823 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2825 u32 n_left_from, *from, thread_index = vm->thread_index;
2826 tcp_main_t *tm = vnet_get_tcp_main ();
2827 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2828 u16 nexts[VLIB_FRAME_SIZE], *next;
2830 tcp_set_time_now (tcp_get_worker (thread_index));
2832 from = vlib_frame_vector_args (frame);
2833 n_left_from = frame->n_vectors;
2834 vlib_get_buffers (vm, from, bufs, n_left_from);
2839 while (n_left_from >= 4)
2841 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2842 tcp_connection_t *tc0, *tc1;
2845 vlib_prefetch_buffer_header (b[2], STORE);
2846 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2848 vlib_prefetch_buffer_header (b[3], STORE);
2849 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2852 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2854 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2856 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2859 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2861 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2862 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2864 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2865 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2867 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2868 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2872 if (PREDICT_TRUE (tc0 != 0))
2874 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2875 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2876 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2880 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2881 b[0]->error = node->errors[error0];
2884 if (PREDICT_TRUE (tc1 != 0))
2886 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2887 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2888 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2892 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2893 b[1]->error = node->errors[error1];
2901 while (n_left_from > 0)
2903 tcp_connection_t *tc0;
2904 u32 error0 = TCP_ERROR_NO_LISTENER;
2906 if (n_left_from > 1)
2908 vlib_prefetch_buffer_header (b[1], STORE);
2909 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2912 next[0] = TCP_INPUT_NEXT_DROP;
2913 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2915 if (PREDICT_TRUE (tc0 != 0))
2917 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2918 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2919 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2923 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2924 b[0]->error = node->errors[error0];
2932 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2933 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2935 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2936 return frame->n_vectors;
2939 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2940 vlib_node_runtime_t * node,
2941 vlib_frame_t * from_frame)
2943 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2944 1 /* is_nolookup */ );
2947 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2948 vlib_node_runtime_t * node,
2949 vlib_frame_t * from_frame)
2951 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2952 1 /* is_nolookup */ );
2956 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2958 .name = "tcp4-input-nolookup",
2959 /* Takes a vector of packets. */
2960 .vector_size = sizeof (u32),
2961 .n_errors = TCP_N_ERROR,
2962 .error_strings = tcp_error_strings,
2963 .n_next_nodes = TCP_INPUT_N_NEXT,
2966 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2967 foreach_tcp4_input_next
2970 .format_buffer = format_tcp_header,
2971 .format_trace = format_tcp_rx_trace,
2976 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2978 .name = "tcp6-input-nolookup",
2979 /* Takes a vector of packets. */
2980 .vector_size = sizeof (u32),
2981 .n_errors = TCP_N_ERROR,
2982 .error_strings = tcp_error_strings,
2983 .n_next_nodes = TCP_INPUT_N_NEXT,
2986 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2987 foreach_tcp6_input_next
2990 .format_buffer = format_tcp_header,
2991 .format_trace = format_tcp_rx_trace,
2995 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2996 vlib_frame_t * from_frame)
2998 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2999 0 /* is_nolookup */ );
3002 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3003 vlib_frame_t * from_frame)
3005 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3006 0 /* is_nolookup */ );
3010 VLIB_REGISTER_NODE (tcp4_input_node) =
3012 .name = "tcp4-input",
3013 /* Takes a vector of packets. */
3014 .vector_size = sizeof (u32),
3015 .n_errors = TCP_N_ERROR,
3016 .error_strings = tcp_error_strings,
3017 .n_next_nodes = TCP_INPUT_N_NEXT,
3020 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3021 foreach_tcp4_input_next
3024 .format_buffer = format_tcp_header,
3025 .format_trace = format_tcp_rx_trace,
3030 VLIB_REGISTER_NODE (tcp6_input_node) =
3032 .name = "tcp6-input",
3033 /* Takes a vector of packets. */
3034 .vector_size = sizeof (u32),
3035 .n_errors = TCP_N_ERROR,
3036 .error_strings = tcp_error_strings,
3037 .n_next_nodes = TCP_INPUT_N_NEXT,
3040 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3041 foreach_tcp6_input_next
3044 .format_buffer = format_tcp_header,
3045 .format_trace = format_tcp_rx_trace,
3049 #ifndef CLIB_MARCH_VARIANT
3051 tcp_dispatch_table_init (tcp_main_t * tm)
3054 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3055 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3057 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3058 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3061 #define _(t,f,n,e) \
3063 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3064 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3067 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3068 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3069 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3070 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3071 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3072 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3073 TCP_ERROR_ACK_INVALID);
3074 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3075 TCP_ERROR_SEGMENT_INVALID);
3076 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3077 TCP_ERROR_SEGMENT_INVALID);
3078 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3079 TCP_ERROR_INVALID_CONNECTION);
3080 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3081 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3082 TCP_ERROR_SEGMENT_INVALID);
3083 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3084 TCP_ERROR_SEGMENT_INVALID);
3085 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3086 TCP_ERROR_SEGMENT_INVALID);
3087 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3088 TCP_ERROR_SEGMENT_INVALID);
3089 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3090 TCP_ERROR_SEGMENT_INVALID);
3091 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3092 TCP_ERROR_SEGMENT_INVALID);
3093 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3094 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3095 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3096 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3097 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3098 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3100 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3101 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3103 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3105 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3106 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3107 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3108 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3110 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3112 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3113 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3114 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3116 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3117 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3118 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3119 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3120 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3121 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3122 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3123 /* SYN-ACK for a SYN */
3124 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3126 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3127 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3128 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3130 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3131 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3133 /* ACK for for established connection -> tcp-established. */
3134 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3135 /* FIN for for established connection -> tcp-established. */
3136 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3137 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3139 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3141 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3142 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3143 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3145 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3146 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3147 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3148 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3149 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3150 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3151 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3152 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3154 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3155 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3157 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3159 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3160 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3161 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3162 /* ACK or FIN-ACK to our FIN */
3163 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3164 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3166 /* FIN in reply to our FIN from the other side */
3167 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3168 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3169 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3171 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3172 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3173 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3174 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3175 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3176 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3177 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3179 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3180 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3181 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3182 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3184 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3186 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3187 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3188 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3189 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3191 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3192 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3193 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3194 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3196 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3198 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3199 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3200 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3201 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3203 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3204 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3206 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3208 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3209 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3210 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3212 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3213 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3214 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3215 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3216 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3217 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3218 /* FIN confirming that the peer (app) has closed */
3219 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3220 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3221 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3223 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3224 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3226 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3227 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3229 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3230 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3232 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3233 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3234 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3235 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3236 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3238 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3240 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3241 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3242 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3244 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3245 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3246 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3247 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3248 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3249 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3250 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3251 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3253 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3254 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3256 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3258 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3259 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3260 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3261 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3262 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3264 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3265 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3267 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3268 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3269 * incoming segment not containing a RST causes a RST to be sent in
3271 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3272 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3273 TCP_ERROR_CONNECTION_CLOSED);
3274 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3275 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3276 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3277 TCP_ERROR_CONNECTION_CLOSED);
3281 static clib_error_t *
3282 tcp_input_init (vlib_main_t * vm)
3284 clib_error_t *error = 0;
3285 tcp_main_t *tm = vnet_get_tcp_main ();
3287 if ((error = vlib_call_init_function (vm, tcp_init)))
3290 /* Initialize dispatch table. */
3291 tcp_dispatch_table_init (tm);
3296 VLIB_INIT_FUNCTION (tcp_input_init);
3298 #endif /* CLIB_MARCH_VARIANT */
3301 * fd.io coding-style-patch-verification: ON
3304 * eval: (c-set-style "gnu")