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.
430 * TODO support us rtt resolution
433 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
439 err = mrtt - tc->srtt;
441 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
442 * The increase should be bound */
443 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
444 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
445 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
449 /* First measurement. */
451 tc->rttvar = mrtt >> 1;
456 * Update RTT estimate and RTO timer
458 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
459 * timing. Middle boxes are known to fiddle with TCP options so we
460 * should give higher priority to ACK timing.
462 * This should be called only if previously sent bytes have been acked.
464 * return 1 if valid rtt 0 otherwise
467 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
471 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
472 * RTT because they're ambiguous. */
473 if (tcp_in_cong_recovery (tc))
475 /* Accept rtt estimates for samples that have not been retransmitted */
476 if ((tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
477 && !(rs->flags & TCP_BTS_IS_RXT))
479 mrtt = rs->rtt_time * THZ;
485 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
487 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
488 tc->mrtt_us = tc->mrtt_us + (sample - tc->mrtt_us) * 0.125;
489 mrtt = clib_max ((u32) (sample * THZ), 1);
490 /* Allow measuring of a new RTT */
493 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
494 * snd_una, i.e., the left side of the send window:
495 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
496 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
498 u32 now = tcp_tstamp (tc);
499 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
504 /* Ignore dubious measurements */
505 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
508 tcp_estimate_rtt (tc, mrtt);
512 /* If we got here something must've been ACKed so make sure boff is 0,
513 * even if mrtt is not valid since we update the rto lower */
521 tcp_estimate_initial_rtt (tcp_connection_t * tc)
523 u8 thread_index = vlib_num_workers ()? 1 : 0;
528 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
529 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
530 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
535 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
536 mrtt = clib_max (mrtt, 1);
537 /* Due to retransmits we don't know the initial mrtt */
538 if (tc->rto_boff && mrtt > 1 * THZ)
540 tc->mrtt_us = (f64) mrtt *TCP_TICK;
543 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
544 tcp_estimate_rtt (tc, mrtt);
549 * Dequeue bytes for connections that have received acks in last burst
552 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
554 u32 thread_index = wrk->vm->thread_index;
555 u32 *pending_deq_acked;
556 tcp_connection_t *tc;
559 if (!vec_len (wrk->pending_deq_acked))
562 pending_deq_acked = wrk->pending_deq_acked;
563 for (i = 0; i < vec_len (pending_deq_acked); i++)
565 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
566 tc->flags &= ~TCP_CONN_DEQ_PENDING;
568 if (PREDICT_FALSE (!tc->burst_acked))
571 /* Dequeue the newly ACKed bytes */
572 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
573 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
575 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
577 if (seq_leq (tc->psh_seq, tc->snd_una))
578 tc->flags &= ~TCP_CONN_PSH_PENDING;
581 if (tcp_is_descheduled (tc))
584 /* If everything has been acked, stop retransmit timer
585 * otherwise update. */
586 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
588 /* Update pacer based on our new cwnd estimate */
589 tcp_connection_tx_pacer_update (tc);
593 _vec_len (wrk->pending_deq_acked) = 0;
597 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
599 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
601 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
602 tc->flags |= TCP_CONN_DEQ_PENDING;
604 tc->burst_acked += tc->bytes_acked;
608 * Try to update snd_wnd based on feedback received from peer.
610 * If successful, and new window is 'effectively' 0, activate persist
614 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
616 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
617 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
618 if (seq_lt (tc->snd_wl1, seq)
619 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
621 tc->snd_wnd = snd_wnd;
624 TCP_EVT (TCP_EVT_SND_WND, tc);
626 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
628 /* Set persist timer if not set and we just got 0 wnd */
629 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
630 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
632 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
633 tcp_persist_timer_set (&wrk->timer_wheel, tc);
638 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
640 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
641 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
644 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
647 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
657 * Init loss recovery/fast recovery.
659 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
660 * updated in @ref tcp_cc_handle_event after fast retransmit
663 tcp_cc_init_congestion (tcp_connection_t * tc)
665 tcp_fastrecovery_on (tc);
666 tc->snd_congestion = tc->snd_nxt;
667 tc->cwnd_acc_bytes = 0;
668 tc->snd_rxt_bytes = 0;
669 tc->rxt_delivered = 0;
670 tc->prr_delivered = 0;
671 tc->prr_start = tc->snd_una;
672 tc->prev_ssthresh = tc->ssthresh;
673 tc->prev_cwnd = tc->cwnd;
675 tc->snd_rxt_ts = tcp_tstamp (tc);
676 tcp_cc_congestion (tc);
678 /* Post retransmit update cwnd to ssthresh and account for the
679 * three segments that have left the network and should've been
680 * buffered at the receiver XXX */
681 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
682 tc->cwnd += 3 * tc->snd_mss;
684 tc->fr_occurences += 1;
685 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
689 tcp_cc_congestion_undo (tcp_connection_t * tc)
691 tc->cwnd = tc->prev_cwnd;
692 tc->ssthresh = tc->prev_ssthresh;
693 tcp_cc_undo_recovery (tc);
694 ASSERT (tc->rto_boff == 0);
695 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
699 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
701 return (tcp_in_recovery (tc) && tc->rto_boff == 1
703 && tcp_opts_tstamp (&tc->rcv_opts)
704 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
708 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
710 return (tcp_cc_is_spurious_timeout_rxt (tc));
714 tcp_should_fastrecover_sack (tcp_connection_t * tc)
716 return (tc->sack_sb.lost_bytes
717 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
718 < tc->sack_sb.sacked_bytes));
722 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
726 /* If of of the two conditions lower hold, reset dupacks because
727 * we're probably after timeout (RFC6582 heuristics).
728 * If Cumulative ack does not cover more than congestion threshold,
730 * 1) The following doesn't hold: The congestion window is greater
731 * than SMSS bytes and the difference between highest_ack
732 * and prev_highest_ack is at most 4*SMSS bytes
733 * 2) Echoed timestamp in the last non-dup ack does not equal the
736 if (seq_leq (tc->snd_una, tc->snd_congestion)
737 && ((!(tc->cwnd > tc->snd_mss
738 && tc->bytes_acked <= 4 * tc->snd_mss))
739 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
745 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
746 || tcp_should_fastrecover_sack (tc));
750 tcp_cc_recover (tcp_connection_t * tc)
752 sack_scoreboard_hole_t *hole;
755 ASSERT (tcp_in_cong_recovery (tc));
757 if (tcp_cc_is_spurious_retransmit (tc))
759 tcp_cc_congestion_undo (tc);
763 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
766 /* Previous recovery left us congested. Continue sending as part
767 * of the current recovery event with an updated snd_congestion */
768 if (tc->sack_sb.sacked_bytes)
770 tc->snd_congestion = tc->snd_nxt;
771 tcp_program_retransmit (tc);
775 tc->rxt_delivered = 0;
776 tc->snd_rxt_bytes = 0;
778 tc->prr_delivered = 0;
780 tc->flags &= ~TCP_CONN_RXT_PENDING;
782 hole = scoreboard_first_hole (&tc->sack_sb);
783 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
784 scoreboard_clear (&tc->sack_sb);
786 if (!tcp_in_recovery (tc) && !is_spurious)
787 tcp_cc_recovered (tc);
789 tcp_fastrecovery_off (tc);
790 tcp_fastrecovery_first_off (tc);
791 tcp_recovery_off (tc);
792 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
794 ASSERT (tc->rto_boff == 0);
795 ASSERT (!tcp_in_cong_recovery (tc));
796 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
802 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
804 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
806 /* Congestion avoidance */
807 tcp_cc_rcv_ack (tc, rs);
809 /* If a cumulative ack, make sure dupacks is 0 */
812 /* When dupacks hits the threshold we only enter fast retransmit if
813 * cumulative ack covers more than snd_congestion. Should snd_una
814 * wrap this test may fail under otherwise valid circumstances.
815 * Therefore, proactively update snd_congestion when wrap detected. */
817 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
818 && seq_gt (tc->snd_congestion, tc->snd_una)))
819 tc->snd_congestion = tc->snd_una - 1;
823 * One function to rule them all ... and in the darkness bind them
826 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
829 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
831 /* If reneging, wait for timer based retransmits */
832 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
836 * If not in recovery, figure out if we should enter
838 if (!tcp_in_cong_recovery (tc))
843 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
844 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
846 if (tcp_should_fastrecover (tc, has_sack))
848 tcp_cc_init_congestion (tc);
851 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
853 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
854 tcp_program_retransmit (tc);
861 * Already in recovery
865 * Process (re)transmit feedback. Output path uses this to decide how much
866 * more data to release into the network
870 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
871 tcp_fastrecovery_first_on (tc);
873 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
874 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
875 - tc->sack_sb.last_bytes_delivered;
881 tc->rcv_dupacks += 1;
882 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
884 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
887 tc->prr_delivered += clib_min (tc->snd_mss,
888 tc->snd_nxt - tc->snd_una);
890 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
894 /* If partial ack, assume that the first un-acked segment was lost */
895 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
896 tcp_fastrecovery_first_on (tc);
900 * See if we can exit and stop retransmitting
902 if (seq_geq (tc->snd_una, tc->snd_congestion))
904 /* If spurious return, we've already updated everything */
905 if (tcp_cc_recover (tc))
907 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
911 /* Treat as congestion avoidance ack */
912 tcp_cc_rcv_ack (tc, rs);
916 tcp_program_retransmit (tc);
919 * Notify cc of the event
922 if (!tc->bytes_acked)
924 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
928 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
929 * reset dupacks to 0. Also needed if in congestion recovery */
932 if (tcp_in_recovery (tc))
933 tcp_cc_rcv_ack (tc, rs);
935 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
939 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
941 if (!tcp_in_cong_recovery (tc))
944 if (tcp_opts_sack_permitted (&tc->rcv_opts))
945 tcp_rcv_sacks (tc, tc->snd_una);
949 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
950 tcp_bt_sample_delivery_rate (tc, rs);
952 tcp_cc_handle_event (tc, rs, 1);
956 * Check if duplicate ack as per RFC5681 Sec. 2
959 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
962 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
963 && seq_gt (tc->snd_nxt, tc->snd_una)
964 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
965 && (prev_snd_wnd == tc->snd_wnd));
969 * Checks if ack is a congestion control event.
972 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
973 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
975 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
976 * defined to be 'duplicate' as well */
977 *is_dack = tc->sack_sb.last_sacked_bytes
978 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
980 return (*is_dack || tcp_in_cong_recovery (tc));
984 * Process incoming ACK
987 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
988 tcp_header_t * th, u32 * error)
990 u32 prev_snd_wnd, prev_snd_una;
991 tcp_rate_sample_t rs = { 0 };
994 TCP_EVT (TCP_EVT_CC_STAT, tc);
996 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
997 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
999 /* We've probably entered recovery and the peer still has some
1000 * of the data we've sent. Update snd_nxt and accept the ack */
1001 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1002 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1004 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1008 tc->errors.above_ack_wnd += 1;
1009 *error = TCP_ERROR_ACK_FUTURE;
1010 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1014 /* If old ACK, probably it's an old dupack */
1015 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1017 tc->errors.below_ack_wnd += 1;
1018 *error = TCP_ERROR_ACK_OLD;
1019 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1021 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1024 tcp_handle_old_ack (tc, &rs);
1026 /* Don't drop yet */
1033 * Looks okay, process feedback
1036 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1037 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1039 prev_snd_wnd = tc->snd_wnd;
1040 prev_snd_una = tc->snd_una;
1041 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1042 vnet_buffer (b)->tcp.ack_number,
1043 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1044 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1045 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1046 tcp_validate_txf_size (tc, tc->bytes_acked);
1048 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1049 tcp_bt_sample_delivery_rate (tc, &rs);
1051 if (tc->bytes_acked)
1053 tcp_program_dequeue (wrk, tc);
1054 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1057 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1060 * Check if we have congestion event
1063 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1065 tcp_cc_handle_event (tc, &rs, is_dack);
1066 tc->dupacks_in += is_dack;
1067 if (!tcp_in_cong_recovery (tc))
1069 *error = TCP_ERROR_ACK_OK;
1072 *error = TCP_ERROR_ACK_DUP;
1073 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1079 * Update congestion control (slow start/congestion avoidance)
1081 tcp_cc_update (tc, &rs);
1082 *error = TCP_ERROR_ACK_OK;
1087 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1089 if (!tcp_disconnect_pending (tc))
1091 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1092 tcp_disconnect_pending_on (tc);
1097 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1099 u32 thread_index, *pending_disconnects, *pending_resets;
1100 tcp_connection_t *tc;
1103 if (vec_len (wrk->pending_disconnects))
1105 thread_index = wrk->vm->thread_index;
1106 pending_disconnects = wrk->pending_disconnects;
1107 for (i = 0; i < vec_len (pending_disconnects); i++)
1109 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1110 tcp_disconnect_pending_off (tc);
1111 session_transport_closing_notify (&tc->connection);
1113 _vec_len (wrk->pending_disconnects) = 0;
1116 if (vec_len (wrk->pending_resets))
1118 thread_index = wrk->vm->thread_index;
1119 pending_resets = wrk->pending_resets;
1120 for (i = 0; i < vec_len (pending_resets); i++)
1122 tc = tcp_connection_get (pending_resets[i], thread_index);
1123 tcp_disconnect_pending_off (tc);
1124 tcp_handle_rst (tc);
1126 _vec_len (wrk->pending_resets) = 0;
1131 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1134 /* Reject out-of-order fins */
1135 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1138 /* Account for the FIN and send ack */
1140 tc->flags |= TCP_CONN_FINRCVD;
1141 tcp_program_ack (tc);
1142 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1143 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1144 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1145 tcp_program_disconnect (wrk, tc);
1146 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1147 tcp_cfg.closewait_time);
1148 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1149 *error = TCP_ERROR_FIN_RCVD;
1152 /** Enqueue data for delivery to application */
1154 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1157 int written, error = TCP_ERROR_ENQUEUED;
1159 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1161 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1162 1 /* queue event */ , 1);
1163 tc->bytes_in += written;
1165 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1167 /* Update rcv_nxt */
1168 if (PREDICT_TRUE (written == data_len))
1170 tc->rcv_nxt += written;
1172 /* If more data written than expected, account for out-of-order bytes. */
1173 else if (written > data_len)
1175 tc->rcv_nxt += written;
1176 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1178 else if (written > 0)
1180 /* We've written something but FIFO is probably full now */
1181 tc->rcv_nxt += written;
1182 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1186 /* Packet made it through for ack processing */
1187 if (tc->rcv_wnd < tc->snd_mss)
1188 return TCP_ERROR_ZERO_RWND;
1190 return TCP_ERROR_FIFO_FULL;
1193 /* Update SACK list if need be */
1194 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1196 /* Remove SACK blocks that have been delivered */
1197 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1203 /** Enqueue out-of-order data */
1205 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1211 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1214 /* Enqueue out-of-order data with relative offset */
1215 rv = session_enqueue_stream_connection (&tc->connection, b,
1216 vnet_buffer (b)->tcp.seq_number -
1217 tc->rcv_nxt, 0 /* queue event */ ,
1220 /* Nothing written */
1223 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1224 return TCP_ERROR_FIFO_FULL;
1227 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1228 tc->bytes_in += data_len;
1230 /* Update SACK list if in use */
1231 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1233 ooo_segment_t *newest;
1236 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1238 /* Get the newest segment from the fifo */
1239 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1242 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1243 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1244 start = tc->rcv_nxt + offset;
1245 end = start + ooo_segment_length (s0->rx_fifo, newest);
1246 tcp_update_sack_list (tc, start, end);
1247 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1248 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1252 return TCP_ERROR_ENQUEUED_OOO;
1256 * Check if ACK could be delayed. If ack can be delayed, it should return
1257 * true for a full frame. If we're always acking return 0.
1260 tcp_can_delack (tcp_connection_t * tc)
1262 /* Send ack if ... */
1264 /* just sent a rcv wnd 0
1265 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1266 /* constrained to send ack */
1267 || (tc->flags & TCP_CONN_SNDACK) != 0
1268 /* we're almost out of tx wnd */
1269 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1276 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1278 u32 discard, first = b->current_length;
1279 vlib_main_t *vm = vlib_get_main ();
1281 /* Handle multi-buffer segments */
1282 if (n_bytes_to_drop > b->current_length)
1284 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1288 discard = clib_min (n_bytes_to_drop, b->current_length);
1289 vlib_buffer_advance (b, discard);
1290 b = vlib_get_buffer (vm, b->next_buffer);
1291 n_bytes_to_drop -= discard;
1293 while (n_bytes_to_drop);
1294 if (n_bytes_to_drop > first)
1295 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1298 vlib_buffer_advance (b, n_bytes_to_drop);
1299 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1304 * Receive buffer for connection and handle acks
1306 * It handles both in order or out-of-order data.
1309 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1312 u32 error, n_bytes_to_drop, n_data_bytes;
1314 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1315 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1316 ASSERT (n_data_bytes);
1317 tc->data_segs_in += 1;
1319 /* Handle out-of-order data */
1320 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1322 /* Old sequence numbers allowed through because they overlapped
1324 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1326 /* Completely in the past (possible retransmit). Ack
1327 * retransmissions since we may not have any data to send */
1328 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1330 tcp_program_dupack (tc);
1331 tc->errors.below_data_wnd++;
1332 error = TCP_ERROR_SEGMENT_OLD;
1336 /* Chop off the bytes in the past and see if what is left
1337 * can be enqueued in order */
1338 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1339 n_data_bytes -= n_bytes_to_drop;
1340 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1341 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1343 error = TCP_ERROR_SEGMENT_OLD;
1349 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1350 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1351 tcp_program_dupack (tc);
1352 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1353 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1354 tc->rcv_las + tc->rcv_wnd);
1360 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1361 * segments can be enqueued after fifo tail offset changes. */
1362 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1363 if (tcp_can_delack (tc))
1365 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1366 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_DELACK,
1367 tcp_cfg.delack_time);
1371 tcp_program_ack (tc);
1379 tcp_header_t tcp_header;
1380 tcp_connection_t tcp_connection;
1384 format_tcp_rx_trace (u8 * s, va_list * args)
1386 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1387 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1388 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1389 tcp_connection_t *tc = &t->tcp_connection;
1390 u32 indent = format_get_indent (s);
1392 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1393 format_tcp_state, tc->state, format_white_space, indent,
1394 format_tcp_header, &t->tcp_header, 128);
1400 format_tcp_rx_trace_short (u8 * s, va_list * args)
1402 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1403 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1404 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1406 s = format (s, "%d -> %d (%U)",
1407 clib_net_to_host_u16 (t->tcp_header.dst_port),
1408 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1409 t->tcp_connection.state);
1415 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1416 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1420 clib_memcpy_fast (&t0->tcp_connection, tc0,
1421 sizeof (t0->tcp_connection));
1425 th0 = tcp_buffer_hdr (b0);
1427 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1431 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1432 vlib_frame_t * frame, u8 is_ip4)
1436 n_left = frame->n_vectors;
1437 from = vlib_frame_vector_args (frame);
1441 tcp_connection_t *tc0;
1448 b0 = vlib_get_buffer (vm, bi0);
1450 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1452 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1453 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1455 th0 = tcp_buffer_hdr (b0);
1456 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1465 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1466 u8 is_ip4, u32 evt, u32 val)
1469 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1471 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1474 #define tcp_maybe_inc_counter(node_id, err, count) \
1476 if (next0 != tcp_next_drop (is_ip4)) \
1477 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1478 tcp6_##node_id##_node.index, is_ip4, err, \
1481 #define tcp_inc_counter(node_id, err, count) \
1482 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1483 tcp6_##node_id##_node.index, is_ip4, \
1485 #define tcp_maybe_inc_err_counter(cnts, err) \
1487 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1489 #define tcp_inc_err_counter(cnts, err, val) \
1493 #define tcp_store_err_counters(node_id, cnts) \
1496 for (i = 0; i < TCP_N_ERROR; i++) \
1498 tcp_inc_counter(node_id, i, cnts[i]); \
1503 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1504 vlib_frame_t * frame, int is_ip4)
1506 u32 thread_index = vm->thread_index, errors = 0;
1507 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1508 u32 n_left_from, *from, *first_buffer;
1509 u16 err_counters[TCP_N_ERROR] = { 0 };
1511 if (node->flags & VLIB_NODE_FLAG_TRACE)
1512 tcp_established_trace_frame (vm, node, frame, is_ip4);
1514 first_buffer = from = vlib_frame_vector_args (frame);
1515 n_left_from = frame->n_vectors;
1517 while (n_left_from > 0)
1519 u32 bi0, error0 = TCP_ERROR_ACK_OK;
1522 tcp_connection_t *tc0;
1524 if (n_left_from > 1)
1527 pb = vlib_get_buffer (vm, from[1]);
1528 vlib_prefetch_buffer_header (pb, LOAD);
1529 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1536 b0 = vlib_get_buffer (vm, bi0);
1537 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1540 if (PREDICT_FALSE (tc0 == 0))
1542 error0 = TCP_ERROR_INVALID_CONNECTION;
1546 th0 = tcp_buffer_hdr (b0);
1548 /* TODO header prediction fast path */
1550 /* 1-4: check SEQ, RST, SYN */
1551 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
1553 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
1557 /* 5: check the ACK field */
1558 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
1561 /* 6: check the URG bit TODO */
1563 /* 7: process the segment text */
1564 if (vnet_buffer (b0)->tcp.data_len)
1565 error0 = tcp_segment_rcv (wrk, tc0, b0);
1567 /* 8: check the FIN bit */
1568 if (PREDICT_FALSE (tcp_is_fin (th0)))
1569 tcp_rcv_fin (wrk, tc0, b0, &error0);
1572 tcp_inc_err_counter (err_counters, error0, 1);
1575 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1577 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1578 tcp_store_err_counters (established, err_counters);
1579 tcp_handle_postponed_dequeues (wrk);
1580 tcp_handle_disconnects (wrk);
1581 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
1583 return frame->n_vectors;
1586 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1587 vlib_node_runtime_t * node,
1588 vlib_frame_t * from_frame)
1590 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1593 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1594 vlib_node_runtime_t * node,
1595 vlib_frame_t * from_frame)
1597 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1601 VLIB_REGISTER_NODE (tcp4_established_node) =
1603 .name = "tcp4-established",
1604 /* Takes a vector of packets. */
1605 .vector_size = sizeof (u32),
1606 .n_errors = TCP_N_ERROR,
1607 .error_strings = tcp_error_strings,
1608 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1611 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1612 foreach_tcp_state_next
1615 .format_trace = format_tcp_rx_trace_short,
1620 VLIB_REGISTER_NODE (tcp6_established_node) =
1622 .name = "tcp6-established",
1623 /* Takes a vector of packets. */
1624 .vector_size = sizeof (u32),
1625 .n_errors = TCP_N_ERROR,
1626 .error_strings = tcp_error_strings,
1627 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1630 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1631 foreach_tcp_state_next
1634 .format_trace = format_tcp_rx_trace_short,
1640 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1643 transport_connection_t *tmp = 0;
1650 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1653 u8 is_ip_valid = 0, val_l, val_r;
1655 if (tc->connection.is_ip4)
1657 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1659 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1660 &tc->connection.lcl_ip.ip4);
1661 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1662 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1663 &tc->connection.rmt_ip.ip4);
1664 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1665 is_ip_valid = val_l && val_r;
1669 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1671 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1672 &tc->connection.lcl_ip.ip6);
1673 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1674 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1675 &tc->connection.rmt_ip.ip6);
1676 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1677 is_ip_valid = val_l && val_r;
1680 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1681 && (tc->state == TCP_STATE_LISTEN
1682 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1686 handle = session_lookup_half_open_handle (&tc->connection);
1687 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1688 tc->c_proto, tc->c_is_ip4);
1692 if (tmp->lcl_port == hdr->dst_port
1693 && tmp->rmt_port == hdr->src_port)
1695 TCP_DBG ("half-open is valid!");
1704 * Lookup transport connection
1706 static tcp_connection_t *
1707 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1711 transport_connection_t *tconn;
1712 tcp_connection_t *tc;
1717 ip4 = vlib_buffer_get_current (b);
1718 tcp = ip4_next_header (ip4);
1719 tconn = session_lookup_connection_wt4 (fib_index,
1724 TRANSPORT_PROTO_TCP,
1725 thread_index, &is_filtered);
1726 tc = tcp_get_connection_from_transport (tconn);
1727 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1732 ip6 = vlib_buffer_get_current (b);
1733 tcp = ip6_next_header (ip6);
1734 tconn = session_lookup_connection_wt6 (fib_index,
1739 TRANSPORT_PROTO_TCP,
1740 thread_index, &is_filtered);
1741 tc = tcp_get_connection_from_transport (tconn);
1742 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1747 static tcp_connection_t *
1748 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1754 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1755 tcp_header_t *tcp = tcp_buffer_hdr (b);
1756 s = session_lookup_listener4 (fib_index,
1758 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1762 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1763 tcp_header_t *tcp = tcp_buffer_hdr (b);
1764 s = session_lookup_listener6 (fib_index,
1766 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1769 if (PREDICT_TRUE (s != 0))
1770 return tcp_get_connection_from_transport (transport_get_listener
1771 (TRANSPORT_PROTO_TCP,
1772 s->connection_index));
1778 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1780 vnet_main_t *vnm = vnet_get_main ();
1781 const dpo_id_t *dpo;
1782 const load_balance_t *lb;
1783 vnet_hw_interface_t *hw_if;
1784 u32 sw_if_idx, lb_idx;
1788 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1789 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1793 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1794 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1797 lb = load_balance_get (lb_idx);
1798 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1800 dpo = load_balance_get_bucket_i (lb, 0);
1802 sw_if_idx = dpo_get_urpf (dpo);
1803 if (PREDICT_FALSE (sw_if_idx == ~0))
1806 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1807 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
1808 tc->cfg_flags |= TCP_CFG_F_TSO;
1812 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1813 vlib_frame_t * from_frame, int is_ip4)
1815 u32 n_left_from, *from, *first_buffer, errors = 0;
1816 u32 my_thread_index = vm->thread_index;
1817 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
1819 from = first_buffer = vlib_frame_vector_args (from_frame);
1820 n_left_from = from_frame->n_vectors;
1822 while (n_left_from > 0)
1824 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
1825 tcp_connection_t *tc0, *new_tc0;
1826 tcp_header_t *tcp0 = 0;
1834 b0 = vlib_get_buffer (vm, bi0);
1836 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
1837 if (PREDICT_FALSE (tc0 == 0))
1839 error0 = TCP_ERROR_INVALID_CONNECTION;
1843 /* Half-open completed recently but the connection was't removed
1844 * yet by the owning thread */
1845 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1847 /* Make sure the connection actually exists */
1848 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
1849 my_thread_index, is_ip4));
1850 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
1854 ack0 = vnet_buffer (b0)->tcp.ack_number;
1855 seq0 = vnet_buffer (b0)->tcp.seq_number;
1856 tcp0 = tcp_buffer_hdr (b0);
1858 /* Crude check to see if the connection handle does not match
1859 * the packet. Probably connection just switched to established */
1860 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1861 || tcp0->src_port != tc0->c_rmt_port))
1863 error0 = TCP_ERROR_INVALID_CONNECTION;
1867 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
1868 && !tcp_syn (tcp0)))
1870 error0 = TCP_ERROR_SEGMENT_INVALID;
1874 /* SYNs consume sequence numbers */
1875 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
1878 * 1. check the ACK bit
1882 * If the ACK bit is set
1883 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1884 * the RST bit is set, if so drop the segment and return)
1885 * <SEQ=SEG.ACK><CTL=RST>
1886 * and discard the segment. Return.
1887 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1891 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
1893 if (!tcp_rst (tcp0))
1894 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1895 error0 = TCP_ERROR_RCV_WND;
1899 /* Make sure ACK is valid */
1900 if (seq_gt (tc0->snd_una, ack0))
1902 error0 = TCP_ERROR_ACK_INVALID;
1908 * 2. check the RST bit
1913 /* If ACK is acceptable, signal client that peer is not
1914 * willing to accept connection and drop connection*/
1916 tcp_rcv_rst (wrk, tc0);
1917 error0 = TCP_ERROR_RST_RCVD;
1922 * 3. check the security and precedence (skipped)
1926 * 4. check the SYN bit
1929 /* No SYN flag. Drop. */
1930 if (!tcp_syn (tcp0))
1932 error0 = TCP_ERROR_SEGMENT_INVALID;
1937 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
1939 error0 = TCP_ERROR_OPTIONS;
1943 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1944 * current thread pool. */
1945 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
1946 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
1947 new_tc0->irs = seq0;
1948 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1949 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1951 /* If this is not the owning thread, wait for syn retransmit to
1952 * expire and cleanup then */
1953 if (tcp_half_open_connection_cleanup (tc0))
1954 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
1956 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
1958 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
1959 new_tc0->tsval_recent_age = tcp_time_now ();
1962 if (tcp_opts_wscale (&new_tc0->rcv_opts))
1963 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
1965 new_tc0->rcv_wscale = 0;
1967 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
1968 << new_tc0->snd_wscale;
1969 new_tc0->snd_wl1 = seq0;
1970 new_tc0->snd_wl2 = ack0;
1972 tcp_connection_init_vars (new_tc0);
1974 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1975 if (PREDICT_TRUE (tcp_ack (tcp0)))
1977 /* Our SYN is ACKed: we have iss < ack = snd_una */
1979 /* TODO Dequeue acknowledged segments if we support Fast Open */
1980 new_tc0->snd_una = ack0;
1981 new_tc0->state = TCP_STATE_ESTABLISHED;
1983 /* Make sure las is initialized for the wnd computation */
1984 new_tc0->rcv_las = new_tc0->rcv_nxt;
1986 /* Notify app that we have connection. If session layer can't
1987 * allocate session send reset */
1988 if (session_stream_connect_notify (&new_tc0->connection,
1991 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
1992 tcp_connection_cleanup (new_tc0);
1993 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1997 new_tc0->tx_fifo_size =
1998 transport_tx_fifo_size (&new_tc0->connection);
1999 /* Update rtt with the syn-ack sample */
2000 tcp_estimate_initial_rtt (new_tc0);
2001 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2002 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2004 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2007 new_tc0->state = TCP_STATE_SYN_RCVD;
2009 /* Notify app that we have connection */
2010 if (session_stream_connect_notify (&new_tc0->connection,
2013 tcp_connection_cleanup (new_tc0);
2014 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2015 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2016 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2020 new_tc0->tx_fifo_size =
2021 transport_tx_fifo_size (&new_tc0->connection);
2022 new_tc0->rtt_ts = 0;
2023 tcp_init_snd_vars (new_tc0);
2024 tcp_send_synack (new_tc0);
2025 error0 = TCP_ERROR_SYNS_RCVD;
2029 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2030 tcp_check_tx_offload (new_tc0, is_ip4);
2032 /* Read data, if any */
2033 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2035 clib_warning ("rcvd data in syn-sent");
2036 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2037 if (error0 == TCP_ERROR_ACK_OK)
2038 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2042 /* Send ack now instead of programming it because connection was
2043 * just established and it's not optional. */
2044 tcp_send_ack (new_tc0);
2049 tcp_inc_counter (syn_sent, error0, 1);
2050 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2052 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2053 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2054 clib_memcpy_fast (&t0->tcp_connection, tc0,
2055 sizeof (t0->tcp_connection));
2059 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2061 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2062 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2063 tcp_handle_disconnects (wrk);
2065 return from_frame->n_vectors;
2068 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2069 vlib_node_runtime_t * node,
2070 vlib_frame_t * from_frame)
2072 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2075 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2076 vlib_node_runtime_t * node,
2077 vlib_frame_t * from_frame)
2079 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2083 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2085 .name = "tcp4-syn-sent",
2086 /* Takes a vector of packets. */
2087 .vector_size = sizeof (u32),
2088 .n_errors = TCP_N_ERROR,
2089 .error_strings = tcp_error_strings,
2090 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2093 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2094 foreach_tcp_state_next
2097 .format_trace = format_tcp_rx_trace_short,
2102 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2104 .name = "tcp6-syn-sent",
2105 /* Takes a vector of packets. */
2106 .vector_size = sizeof (u32),
2107 .n_errors = TCP_N_ERROR,
2108 .error_strings = tcp_error_strings,
2109 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2112 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2113 foreach_tcp_state_next
2116 .format_trace = format_tcp_rx_trace_short,
2121 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2122 * as per RFC793 p. 64
2125 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2126 vlib_frame_t * from_frame, int is_ip4)
2128 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2129 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2130 u32 n_left_from, *from, max_dequeue;
2132 from = first_buffer = vlib_frame_vector_args (from_frame);
2133 n_left_from = from_frame->n_vectors;
2135 while (n_left_from > 0)
2137 u32 bi0, error0 = TCP_ERROR_NONE;
2138 tcp_header_t *tcp0 = 0;
2139 tcp_connection_t *tc0;
2147 b0 = vlib_get_buffer (vm, bi0);
2148 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2150 if (PREDICT_FALSE (tc0 == 0))
2152 error0 = TCP_ERROR_INVALID_CONNECTION;
2156 tcp0 = tcp_buffer_hdr (b0);
2157 is_fin0 = tcp_is_fin (tcp0);
2161 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2163 tcp_connection_t *tmp;
2164 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2166 if (tmp->state != tc0->state)
2168 if (tc0->state != TCP_STATE_CLOSED)
2169 clib_warning ("state changed");
2176 * Special treatment for CLOSED
2178 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2180 error0 = TCP_ERROR_CONNECTION_CLOSED;
2185 * For all other states (except LISTEN)
2188 /* 1-4: check SEQ, RST, SYN */
2189 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2192 /* 5: check the ACK field */
2195 case TCP_STATE_SYN_RCVD:
2197 /* Make sure the segment is exactly right */
2198 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2200 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2201 error0 = TCP_ERROR_SEGMENT_INVALID;
2206 * If the segment acknowledgment is not acceptable, form a
2208 * <SEQ=SEG.ACK><CTL=RST>
2211 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2213 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2214 error0 = TCP_ERROR_SEGMENT_INVALID;
2218 /* Update rtt and rto */
2219 tcp_estimate_initial_rtt (tc0);
2220 tcp_connection_tx_pacer_update (tc0);
2222 /* Switch state to ESTABLISHED */
2223 tc0->state = TCP_STATE_ESTABLISHED;
2224 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2226 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2227 tcp_check_tx_offload (tc0, is_ip4);
2229 /* Initialize session variables */
2230 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2231 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2232 << tc0->rcv_opts.wscale;
2233 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2234 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2236 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2237 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc0);
2238 if (session_stream_accept_notify (&tc0->connection))
2240 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2241 tcp_send_reset (tc0);
2242 session_transport_delete_notify (&tc0->connection);
2243 tcp_connection_cleanup (tc0);
2246 error0 = TCP_ERROR_ACK_OK;
2248 case TCP_STATE_ESTABLISHED:
2249 /* We can get packets in established state here because they
2250 * were enqueued before state change */
2251 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2255 case TCP_STATE_FIN_WAIT_1:
2256 /* In addition to the processing for the ESTABLISHED state, if
2257 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2258 * continue processing in that state. */
2259 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2262 /* Still have to send the FIN */
2263 if (tc0->flags & TCP_CONN_FINPNDG)
2265 /* TX fifo finally drained */
2266 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2267 if (max_dequeue <= tc0->burst_acked)
2269 /* If a fin was received and data was acked extend wait */
2270 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2271 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2272 tcp_cfg.closewait_time);
2274 /* If FIN is ACKed */
2275 else if (tc0->snd_una == tc0->snd_nxt)
2277 /* Stop all retransmit timers because we have nothing more
2279 tcp_connection_timers_reset (tc0);
2281 /* We already have a FIN but didn't transition to CLOSING
2282 * because of outstanding tx data. Close the connection. */
2283 if (tc0->flags & TCP_CONN_FINRCVD)
2285 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2286 session_transport_closed_notify (&tc0->connection);
2287 tcp_program_cleanup (wrk, tc0);
2291 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2292 /* Enable waitclose because we're willing to wait for peer's
2293 * FIN but not indefinitely. */
2294 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2295 tcp_cfg.finwait2_time);
2297 /* Don't try to deq the FIN acked */
2298 if (tc0->burst_acked > 1)
2299 session_tx_fifo_dequeue_drop (&tc0->connection,
2300 tc0->burst_acked - 1);
2301 tc0->burst_acked = 0;
2304 case TCP_STATE_FIN_WAIT_2:
2305 /* In addition to the processing for the ESTABLISHED state, if
2306 * the retransmission queue is empty, the user's CLOSE can be
2307 * acknowledged ("ok") but do not delete the TCB. */
2308 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2310 tc0->burst_acked = 0;
2312 case TCP_STATE_CLOSE_WAIT:
2313 /* Do the same processing as for the ESTABLISHED state. */
2314 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2317 if (!(tc0->flags & TCP_CONN_FINPNDG))
2320 /* Still have outstanding tx data */
2321 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2322 if (max_dequeue > tc0->burst_acked)
2326 tcp_connection_timers_reset (tc0);
2327 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2328 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2329 tcp_cfg.lastack_time);
2331 case TCP_STATE_CLOSING:
2332 /* In addition to the processing for the ESTABLISHED state, if
2333 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2334 * otherwise ignore the segment. */
2335 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2338 if (tc0->snd_una != tc0->snd_nxt)
2341 tcp_connection_timers_reset (tc0);
2342 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2343 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2344 tcp_cfg.timewait_time);
2345 session_transport_closed_notify (&tc0->connection);
2349 case TCP_STATE_LAST_ACK:
2350 /* The only thing that [should] arrive in this state is an
2351 * acknowledgment of our FIN. If our FIN is now acknowledged,
2352 * delete the TCB, enter the CLOSED state, and return. */
2354 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2357 /* Apparently our ACK for the peer's FIN was lost */
2358 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2364 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2365 session_transport_closed_notify (&tc0->connection);
2367 /* Don't free the connection from the data path since
2368 * we can't ensure that we have no packets already enqueued
2369 * to output. Rely instead on the waitclose timer */
2370 tcp_connection_timers_reset (tc0);
2371 tcp_program_cleanup (tcp_get_worker (tc0->c_thread_index), tc0);
2376 case TCP_STATE_TIME_WAIT:
2377 /* The only thing that can arrive in this state is a
2378 * retransmission of the remote FIN. Acknowledge it, and restart
2379 * the 2 MSL timeout. */
2381 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2387 tcp_program_ack (tc0);
2388 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2389 tcp_cfg.timewait_time);
2397 /* 6: check the URG bit TODO */
2399 /* 7: process the segment text */
2402 case TCP_STATE_ESTABLISHED:
2403 case TCP_STATE_FIN_WAIT_1:
2404 case TCP_STATE_FIN_WAIT_2:
2405 if (vnet_buffer (b0)->tcp.data_len)
2406 error0 = tcp_segment_rcv (wrk, tc0, b0);
2408 case TCP_STATE_CLOSE_WAIT:
2409 case TCP_STATE_CLOSING:
2410 case TCP_STATE_LAST_ACK:
2411 case TCP_STATE_TIME_WAIT:
2412 /* This should not occur, since a FIN has been received from the
2413 * remote side. Ignore the segment text. */
2417 /* 8: check the FIN bit */
2421 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
2425 case TCP_STATE_ESTABLISHED:
2426 /* Account for the FIN and send ack */
2428 tcp_program_ack (tc0);
2429 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
2430 tcp_program_disconnect (wrk, tc0);
2431 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2432 tcp_cfg.closewait_time);
2434 case TCP_STATE_SYN_RCVD:
2435 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2436 * notified yet, set a cleanup timer instead of relying on
2437 * disconnect notify and the implicit close call. */
2438 tcp_connection_timers_reset (tc0);
2441 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2442 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2443 tcp_cfg.lastack_time);
2445 case TCP_STATE_CLOSE_WAIT:
2446 case TCP_STATE_CLOSING:
2447 case TCP_STATE_LAST_ACK:
2450 case TCP_STATE_FIN_WAIT_1:
2453 if (tc0->flags & TCP_CONN_FINPNDG)
2455 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2456 * sending it. Since we already received a fin, do not wait
2458 tc0->flags |= TCP_CONN_FINRCVD;
2459 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2460 tcp_cfg.closewait_time);
2464 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2465 tcp_program_ack (tc0);
2466 /* Wait for ACK for our FIN but not forever */
2467 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2468 tcp_cfg.closing_time);
2471 case TCP_STATE_FIN_WAIT_2:
2472 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2474 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2475 tcp_connection_timers_reset (tc0);
2476 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2477 tcp_cfg.timewait_time);
2478 tcp_program_ack (tc0);
2479 session_transport_closed_notify (&tc0->connection);
2481 case TCP_STATE_TIME_WAIT:
2482 /* Remain in the TIME-WAIT state. Restart the time-wait
2485 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2486 tcp_cfg.timewait_time);
2489 error0 = TCP_ERROR_FIN_RCVD;
2493 tcp_inc_counter (rcv_process, error0, 1);
2494 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2496 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2497 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2501 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2503 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2504 tcp_handle_postponed_dequeues (wrk);
2505 tcp_handle_disconnects (wrk);
2506 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2508 return from_frame->n_vectors;
2511 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2512 vlib_node_runtime_t * node,
2513 vlib_frame_t * from_frame)
2515 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2518 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2519 vlib_node_runtime_t * node,
2520 vlib_frame_t * from_frame)
2522 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2526 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2528 .name = "tcp4-rcv-process",
2529 /* Takes a vector of packets. */
2530 .vector_size = sizeof (u32),
2531 .n_errors = TCP_N_ERROR,
2532 .error_strings = tcp_error_strings,
2533 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2536 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2537 foreach_tcp_state_next
2540 .format_trace = format_tcp_rx_trace_short,
2545 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2547 .name = "tcp6-rcv-process",
2548 /* Takes a vector of packets. */
2549 .vector_size = sizeof (u32),
2550 .n_errors = TCP_N_ERROR,
2551 .error_strings = tcp_error_strings,
2552 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2555 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2556 foreach_tcp_state_next
2559 .format_trace = format_tcp_rx_trace_short,
2564 * LISTEN state processing as per RFC 793 p. 65
2567 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2568 vlib_frame_t * from_frame, int is_ip4)
2570 u32 n_left_from, *from, n_syns = 0, *first_buffer;
2571 u32 thread_index = vm->thread_index;
2573 from = first_buffer = vlib_frame_vector_args (from_frame);
2574 n_left_from = from_frame->n_vectors;
2576 while (n_left_from > 0)
2578 u32 bi, error = TCP_ERROR_NONE;
2579 tcp_connection_t *lc, *child;
2586 b = vlib_get_buffer (vm, bi);
2588 lc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2589 if (PREDICT_FALSE (lc == 0))
2591 tcp_connection_t *tc;
2592 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2594 if (tc->state != TCP_STATE_TIME_WAIT)
2596 error = TCP_ERROR_CREATE_EXISTS;
2599 lc = tcp_lookup_listener (b, tc->c_fib_index, is_ip4);
2600 /* clean up the old session */
2601 tcp_connection_del (tc);
2604 /* Make sure connection wasn't just created */
2605 child = tcp_lookup_connection (lc->c_fib_index, b, thread_index,
2607 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2609 error = TCP_ERROR_CREATE_EXISTS;
2613 /* Create child session. For syn-flood protection use filter */
2615 /* 1. first check for an RST: handled in dispatch */
2616 /* if (tcp_rst (th0))
2620 /* 2. second check for an ACK: handled in dispatch */
2621 /* if (tcp_ack (th0))
2623 tcp_send_reset (b0, is_ip4);
2628 /* 3. check for a SYN (did that already) */
2630 /* Create child session and send SYN-ACK */
2631 child = tcp_connection_alloc (thread_index);
2633 if (tcp_options_parse (tcp_buffer_hdr (b), &child->rcv_opts, 1))
2635 error = TCP_ERROR_OPTIONS;
2636 tcp_connection_free (child);
2640 tcp_init_w_buffer (child, b, is_ip4);
2642 child->state = TCP_STATE_SYN_RCVD;
2643 child->c_fib_index = lc->c_fib_index;
2644 child->cc_algo = lc->cc_algo;
2645 tcp_connection_init_vars (child);
2646 child->rto = TCP_RTO_MIN;
2648 if (session_stream_accept (&child->connection, lc->c_s_index,
2649 lc->c_thread_index, 0 /* notify */ ))
2651 tcp_connection_cleanup (child);
2652 error = TCP_ERROR_CREATE_SESSION_FAIL;
2656 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2658 tcp_send_synack (child);
2660 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2664 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
2667 t = vlib_add_trace (vm, node, b, sizeof (*t));
2668 clib_memcpy_fast (&t->tcp_header, tcp_buffer_hdr (b),
2669 sizeof (t->tcp_header));
2670 clib_memcpy_fast (&t->tcp_connection, lc,
2671 sizeof (t->tcp_connection));
2674 n_syns += (error == TCP_ERROR_NONE);
2677 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2678 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2680 return from_frame->n_vectors;
2683 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2684 vlib_frame_t * from_frame)
2686 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2689 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2690 vlib_frame_t * from_frame)
2692 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2696 VLIB_REGISTER_NODE (tcp4_listen_node) =
2698 .name = "tcp4-listen",
2699 /* Takes a vector of packets. */
2700 .vector_size = sizeof (u32),
2701 .n_errors = TCP_N_ERROR,
2702 .error_strings = tcp_error_strings,
2703 .n_next_nodes = TCP_LISTEN_N_NEXT,
2706 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2707 foreach_tcp_state_next
2710 .format_trace = format_tcp_rx_trace_short,
2715 VLIB_REGISTER_NODE (tcp6_listen_node) =
2717 .name = "tcp6-listen",
2718 /* Takes a vector of packets. */
2719 .vector_size = sizeof (u32),
2720 .n_errors = TCP_N_ERROR,
2721 .error_strings = tcp_error_strings,
2722 .n_next_nodes = TCP_LISTEN_N_NEXT,
2725 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2726 foreach_tcp_state_next
2729 .format_trace = format_tcp_rx_trace_short,
2733 typedef enum _tcp_input_next
2735 TCP_INPUT_NEXT_DROP,
2736 TCP_INPUT_NEXT_LISTEN,
2737 TCP_INPUT_NEXT_RCV_PROCESS,
2738 TCP_INPUT_NEXT_SYN_SENT,
2739 TCP_INPUT_NEXT_ESTABLISHED,
2740 TCP_INPUT_NEXT_RESET,
2741 TCP_INPUT_NEXT_PUNT,
2745 #define foreach_tcp4_input_next \
2746 _ (DROP, "ip4-drop") \
2747 _ (LISTEN, "tcp4-listen") \
2748 _ (RCV_PROCESS, "tcp4-rcv-process") \
2749 _ (SYN_SENT, "tcp4-syn-sent") \
2750 _ (ESTABLISHED, "tcp4-established") \
2751 _ (RESET, "tcp4-reset") \
2752 _ (PUNT, "ip4-punt")
2754 #define foreach_tcp6_input_next \
2755 _ (DROP, "ip6-drop") \
2756 _ (LISTEN, "tcp6-listen") \
2757 _ (RCV_PROCESS, "tcp6-rcv-process") \
2758 _ (SYN_SENT, "tcp6-syn-sent") \
2759 _ (ESTABLISHED, "tcp6-established") \
2760 _ (RESET, "tcp6-reset") \
2761 _ (PUNT, "ip6-punt")
2763 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2766 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2767 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2769 tcp_connection_t *tc;
2774 for (i = 0; i < n_bufs; i++)
2776 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2778 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2779 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2781 tcp = vlib_buffer_get_current (bs[i]);
2782 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2788 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2790 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2792 *next = TCP_INPUT_NEXT_DROP;
2794 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2796 *next = TCP_INPUT_NEXT_PUNT;
2797 *error = TCP_ERROR_PUNT;
2801 *next = TCP_INPUT_NEXT_RESET;
2802 *error = TCP_ERROR_NO_LISTENER;
2807 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2808 vlib_buffer_t * b, u16 * next,
2809 vlib_node_runtime_t * error_node)
2815 tcp = tcp_buffer_hdr (b);
2816 flags = tcp->flags & filter_flags;
2817 *next = tm->dispatch_table[tc->state][flags].next;
2818 error = tm->dispatch_table[tc->state][flags].error;
2821 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2823 b->error = error_node->errors[error];
2824 if (error == TCP_ERROR_DISPATCH)
2825 clib_warning ("tcp conn %u disp error state %U flags %U",
2826 tc->c_c_index, format_tcp_state, tc->state,
2827 format_tcp_flags, (int) flags);
2832 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2833 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2835 u32 n_left_from, *from, thread_index = vm->thread_index;
2836 tcp_main_t *tm = vnet_get_tcp_main ();
2837 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2838 u16 nexts[VLIB_FRAME_SIZE], *next;
2840 tcp_set_time_now (tcp_get_worker (thread_index));
2842 from = vlib_frame_vector_args (frame);
2843 n_left_from = frame->n_vectors;
2844 vlib_get_buffers (vm, from, bufs, n_left_from);
2849 while (n_left_from >= 4)
2851 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2852 tcp_connection_t *tc0, *tc1;
2855 vlib_prefetch_buffer_header (b[2], STORE);
2856 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2858 vlib_prefetch_buffer_header (b[3], STORE);
2859 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2862 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2864 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2866 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2869 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2871 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2872 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2874 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2875 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2877 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2878 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2882 if (PREDICT_TRUE (tc0 != 0))
2884 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2885 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2886 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2890 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2891 b[0]->error = node->errors[error0];
2894 if (PREDICT_TRUE (tc1 != 0))
2896 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2897 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2898 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2902 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2903 b[1]->error = node->errors[error1];
2911 while (n_left_from > 0)
2913 tcp_connection_t *tc0;
2914 u32 error0 = TCP_ERROR_NO_LISTENER;
2916 if (n_left_from > 1)
2918 vlib_prefetch_buffer_header (b[1], STORE);
2919 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2922 next[0] = TCP_INPUT_NEXT_DROP;
2923 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2925 if (PREDICT_TRUE (tc0 != 0))
2927 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2928 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2929 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2933 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2934 b[0]->error = node->errors[error0];
2942 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2943 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2945 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2946 return frame->n_vectors;
2949 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2950 vlib_node_runtime_t * node,
2951 vlib_frame_t * from_frame)
2953 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2954 1 /* is_nolookup */ );
2957 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2958 vlib_node_runtime_t * node,
2959 vlib_frame_t * from_frame)
2961 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2962 1 /* is_nolookup */ );
2966 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2968 .name = "tcp4-input-nolookup",
2969 /* Takes a vector of packets. */
2970 .vector_size = sizeof (u32),
2971 .n_errors = TCP_N_ERROR,
2972 .error_strings = tcp_error_strings,
2973 .n_next_nodes = TCP_INPUT_N_NEXT,
2976 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2977 foreach_tcp4_input_next
2980 .format_buffer = format_tcp_header,
2981 .format_trace = format_tcp_rx_trace,
2986 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2988 .name = "tcp6-input-nolookup",
2989 /* Takes a vector of packets. */
2990 .vector_size = sizeof (u32),
2991 .n_errors = TCP_N_ERROR,
2992 .error_strings = tcp_error_strings,
2993 .n_next_nodes = TCP_INPUT_N_NEXT,
2996 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2997 foreach_tcp6_input_next
3000 .format_buffer = format_tcp_header,
3001 .format_trace = format_tcp_rx_trace,
3005 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3006 vlib_frame_t * from_frame)
3008 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3009 0 /* is_nolookup */ );
3012 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3013 vlib_frame_t * from_frame)
3015 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3016 0 /* is_nolookup */ );
3020 VLIB_REGISTER_NODE (tcp4_input_node) =
3022 .name = "tcp4-input",
3023 /* Takes a vector of packets. */
3024 .vector_size = sizeof (u32),
3025 .n_errors = TCP_N_ERROR,
3026 .error_strings = tcp_error_strings,
3027 .n_next_nodes = TCP_INPUT_N_NEXT,
3030 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3031 foreach_tcp4_input_next
3034 .format_buffer = format_tcp_header,
3035 .format_trace = format_tcp_rx_trace,
3040 VLIB_REGISTER_NODE (tcp6_input_node) =
3042 .name = "tcp6-input",
3043 /* Takes a vector of packets. */
3044 .vector_size = sizeof (u32),
3045 .n_errors = TCP_N_ERROR,
3046 .error_strings = tcp_error_strings,
3047 .n_next_nodes = TCP_INPUT_N_NEXT,
3050 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3051 foreach_tcp6_input_next
3054 .format_buffer = format_tcp_header,
3055 .format_trace = format_tcp_rx_trace,
3059 #ifndef CLIB_MARCH_VARIANT
3061 tcp_dispatch_table_init (tcp_main_t * tm)
3064 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3065 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3067 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3068 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3071 #define _(t,f,n,e) \
3073 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3074 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3077 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3078 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3079 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3080 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3081 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3082 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3083 TCP_ERROR_ACK_INVALID);
3084 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3085 TCP_ERROR_SEGMENT_INVALID);
3086 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3087 TCP_ERROR_SEGMENT_INVALID);
3088 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3089 TCP_ERROR_INVALID_CONNECTION);
3090 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3091 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3092 TCP_ERROR_SEGMENT_INVALID);
3093 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3094 TCP_ERROR_SEGMENT_INVALID);
3095 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3096 TCP_ERROR_SEGMENT_INVALID);
3097 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3098 TCP_ERROR_SEGMENT_INVALID);
3099 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3100 TCP_ERROR_SEGMENT_INVALID);
3101 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3102 TCP_ERROR_SEGMENT_INVALID);
3103 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3104 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3105 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3106 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3107 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3108 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3110 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3111 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3113 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3115 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3116 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3117 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3118 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3120 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3122 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3123 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3124 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3126 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3127 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3128 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3129 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3130 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3131 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3132 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3133 /* SYN-ACK for a SYN */
3134 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3136 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3137 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3138 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3140 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3141 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3143 /* ACK for for established connection -> tcp-established. */
3144 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3145 /* FIN for for established connection -> tcp-established. */
3146 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3147 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3149 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3151 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3152 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3153 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3155 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3156 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3157 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3158 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3159 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3160 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3161 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3162 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3164 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3165 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3167 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3169 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3170 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3171 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3172 /* ACK or FIN-ACK to our FIN */
3173 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3174 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3176 /* FIN in reply to our FIN from the other side */
3177 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3178 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3179 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3181 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3182 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3183 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3184 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3185 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3186 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3187 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3189 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3190 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3191 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3192 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3194 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3196 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3197 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3198 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3199 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3201 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3202 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3203 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3204 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3206 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3208 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3209 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3210 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3211 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3213 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3214 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3216 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3218 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3219 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3220 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3222 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3223 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3224 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3225 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3226 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3227 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 /* FIN confirming that the peer (app) has closed */
3229 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3230 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3231 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3233 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3236 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3237 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3239 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3240 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3242 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3243 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3244 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3245 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3247 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3249 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3250 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3251 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3253 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3254 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3255 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3256 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3257 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3258 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3259 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3260 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3262 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3263 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3265 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3267 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3268 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3269 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3270 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3271 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3273 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3274 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3276 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3277 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3278 * incoming segment not containing a RST causes a RST to be sent in
3280 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3281 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3282 TCP_ERROR_CONNECTION_CLOSED);
3283 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3284 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3285 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3286 TCP_ERROR_CONNECTION_CLOSED);
3290 static clib_error_t *
3291 tcp_input_init (vlib_main_t * vm)
3293 clib_error_t *error = 0;
3294 tcp_main_t *tm = vnet_get_tcp_main ();
3296 if ((error = vlib_call_init_function (vm, tcp_init)))
3299 /* Initialize dispatch table. */
3300 tcp_dispatch_table_init (tm);
3305 VLIB_INIT_FUNCTION (tcp_input_init);
3307 #endif /* CLIB_MARCH_VARIANT */
3310 * fd.io coding-style-patch-verification: ON
3313 * eval: (c-set-style "gnu")