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 (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))
631 tcp_persist_timer_set (tc);
635 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
636 tcp_persist_timer_reset (tc);
638 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
641 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
651 * Init loss recovery/fast recovery.
653 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
654 * updated in @ref tcp_cc_handle_event after fast retransmit
657 tcp_cc_init_congestion (tcp_connection_t * tc)
659 tcp_fastrecovery_on (tc);
660 tc->snd_congestion = tc->snd_nxt;
661 tc->cwnd_acc_bytes = 0;
662 tc->snd_rxt_bytes = 0;
663 tc->rxt_delivered = 0;
664 tc->prr_delivered = 0;
665 tc->prr_start = tc->snd_una;
666 tc->prev_ssthresh = tc->ssthresh;
667 tc->prev_cwnd = tc->cwnd;
669 tc->snd_rxt_ts = tcp_tstamp (tc);
670 tcp_cc_congestion (tc);
672 /* Post retransmit update cwnd to ssthresh and account for the
673 * three segments that have left the network and should've been
674 * buffered at the receiver XXX */
675 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
676 tc->cwnd += 3 * tc->snd_mss;
678 tc->fr_occurences += 1;
679 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
683 tcp_cc_congestion_undo (tcp_connection_t * tc)
685 tc->cwnd = tc->prev_cwnd;
686 tc->ssthresh = tc->prev_ssthresh;
687 tcp_cc_undo_recovery (tc);
688 ASSERT (tc->rto_boff == 0);
689 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
693 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
695 return (tcp_in_recovery (tc) && tc->rto_boff == 1
697 && tcp_opts_tstamp (&tc->rcv_opts)
698 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
702 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
704 return (tcp_cc_is_spurious_timeout_rxt (tc));
708 tcp_should_fastrecover_sack (tcp_connection_t * tc)
710 return (tc->sack_sb.lost_bytes
711 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
712 < tc->sack_sb.sacked_bytes));
716 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
720 /* If of of the two conditions lower hold, reset dupacks because
721 * we're probably after timeout (RFC6582 heuristics).
722 * If Cumulative ack does not cover more than congestion threshold,
724 * 1) The following doesn't hold: The congestion window is greater
725 * than SMSS bytes and the difference between highest_ack
726 * and prev_highest_ack is at most 4*SMSS bytes
727 * 2) Echoed timestamp in the last non-dup ack does not equal the
730 if (seq_leq (tc->snd_una, tc->snd_congestion)
731 && ((!(tc->cwnd > tc->snd_mss
732 && tc->bytes_acked <= 4 * tc->snd_mss))
733 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
739 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
740 || tcp_should_fastrecover_sack (tc));
744 tcp_cc_recover (tcp_connection_t * tc)
746 sack_scoreboard_hole_t *hole;
749 ASSERT (tcp_in_cong_recovery (tc));
751 if (tcp_cc_is_spurious_retransmit (tc))
753 tcp_cc_congestion_undo (tc);
757 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
760 /* Previous recovery left us congested. Continue sending as part
761 * of the current recovery event with an updated snd_congestion */
762 if (tc->sack_sb.sacked_bytes)
764 tc->snd_congestion = tc->snd_nxt;
765 tcp_program_retransmit (tc);
769 tc->rxt_delivered = 0;
770 tc->snd_rxt_bytes = 0;
772 tc->prr_delivered = 0;
774 tc->flags &= ~TCP_CONN_RXT_PENDING;
776 hole = scoreboard_first_hole (&tc->sack_sb);
777 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
778 scoreboard_clear (&tc->sack_sb);
780 if (!tcp_in_recovery (tc) && !is_spurious)
781 tcp_cc_recovered (tc);
783 tcp_fastrecovery_off (tc);
784 tcp_fastrecovery_first_off (tc);
785 tcp_recovery_off (tc);
786 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
788 ASSERT (tc->rto_boff == 0);
789 ASSERT (!tcp_in_cong_recovery (tc));
790 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
796 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
798 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
800 /* Congestion avoidance */
801 tcp_cc_rcv_ack (tc, rs);
803 /* If a cumulative ack, make sure dupacks is 0 */
806 /* When dupacks hits the threshold we only enter fast retransmit if
807 * cumulative ack covers more than snd_congestion. Should snd_una
808 * wrap this test may fail under otherwise valid circumstances.
809 * Therefore, proactively update snd_congestion when wrap detected. */
811 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
812 && seq_gt (tc->snd_congestion, tc->snd_una)))
813 tc->snd_congestion = tc->snd_una - 1;
817 * One function to rule them all ... and in the darkness bind them
820 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
823 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
825 /* If reneging, wait for timer based retransmits */
826 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
830 * If not in recovery, figure out if we should enter
832 if (!tcp_in_cong_recovery (tc))
837 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
838 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
840 if (tcp_should_fastrecover (tc, has_sack))
842 tcp_cc_init_congestion (tc);
845 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
847 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
848 tcp_program_retransmit (tc);
855 * Already in recovery
859 * Process (re)transmit feedback. Output path uses this to decide how much
860 * more data to release into the network
864 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
865 tcp_fastrecovery_first_on (tc);
867 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
868 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
869 - tc->sack_sb.last_bytes_delivered;
875 tc->rcv_dupacks += 1;
876 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
878 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
881 tc->prr_delivered += clib_min (tc->snd_mss,
882 tc->snd_nxt - tc->snd_una);
884 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
888 /* If partial ack, assume that the first un-acked segment was lost */
889 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
890 tcp_fastrecovery_first_on (tc);
894 * See if we can exit and stop retransmitting
896 if (seq_geq (tc->snd_una, tc->snd_congestion))
898 /* If spurious return, we've already updated everything */
899 if (tcp_cc_recover (tc))
901 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
905 /* Treat as congestion avoidance ack */
906 tcp_cc_rcv_ack (tc, rs);
910 tcp_program_retransmit (tc);
913 * Notify cc of the event
916 if (!tc->bytes_acked)
918 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
922 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
923 * reset dupacks to 0. Also needed if in congestion recovery */
926 if (tcp_in_recovery (tc))
927 tcp_cc_rcv_ack (tc, rs);
929 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
933 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
935 if (!tcp_in_cong_recovery (tc))
938 if (tcp_opts_sack_permitted (&tc->rcv_opts))
939 tcp_rcv_sacks (tc, tc->snd_una);
943 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
944 tcp_bt_sample_delivery_rate (tc, rs);
946 tcp_cc_handle_event (tc, rs, 1);
950 * Check if duplicate ack as per RFC5681 Sec. 2
953 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
956 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
957 && seq_gt (tc->snd_nxt, tc->snd_una)
958 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
959 && (prev_snd_wnd == tc->snd_wnd));
963 * Checks if ack is a congestion control event.
966 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
967 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
969 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
970 * defined to be 'duplicate' as well */
971 *is_dack = tc->sack_sb.last_sacked_bytes
972 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
974 return (*is_dack || tcp_in_cong_recovery (tc));
978 * Process incoming ACK
981 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
982 tcp_header_t * th, u32 * error)
984 u32 prev_snd_wnd, prev_snd_una;
985 tcp_rate_sample_t rs = { 0 };
988 TCP_EVT (TCP_EVT_CC_STAT, tc);
990 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
991 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
993 /* We've probably entered recovery and the peer still has some
994 * of the data we've sent. Update snd_nxt and accept the ack */
995 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
996 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
998 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1002 tc->errors.above_ack_wnd += 1;
1003 *error = TCP_ERROR_ACK_FUTURE;
1004 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1008 /* If old ACK, probably it's an old dupack */
1009 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1011 tc->errors.below_ack_wnd += 1;
1012 *error = TCP_ERROR_ACK_OLD;
1013 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1015 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1018 tcp_handle_old_ack (tc, &rs);
1020 /* Don't drop yet */
1027 * Looks okay, process feedback
1030 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1031 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1033 prev_snd_wnd = tc->snd_wnd;
1034 prev_snd_una = tc->snd_una;
1035 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1036 vnet_buffer (b)->tcp.ack_number,
1037 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1038 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1039 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1040 tcp_validate_txf_size (tc, tc->bytes_acked);
1042 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1043 tcp_bt_sample_delivery_rate (tc, &rs);
1045 if (tc->bytes_acked)
1047 tcp_program_dequeue (wrk, tc);
1048 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1051 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1054 * Check if we have congestion event
1057 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1059 tcp_cc_handle_event (tc, &rs, is_dack);
1060 tc->dupacks_in += is_dack;
1061 if (!tcp_in_cong_recovery (tc))
1063 *error = TCP_ERROR_ACK_OK;
1066 *error = TCP_ERROR_ACK_DUP;
1067 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1073 * Update congestion control (slow start/congestion avoidance)
1075 tcp_cc_update (tc, &rs);
1076 *error = TCP_ERROR_ACK_OK;
1081 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1083 if (!tcp_disconnect_pending (tc))
1085 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1086 tcp_disconnect_pending_on (tc);
1091 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1093 u32 thread_index, *pending_disconnects, *pending_resets;
1094 tcp_connection_t *tc;
1097 if (vec_len (wrk->pending_disconnects))
1099 thread_index = wrk->vm->thread_index;
1100 pending_disconnects = wrk->pending_disconnects;
1101 for (i = 0; i < vec_len (pending_disconnects); i++)
1103 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1104 tcp_disconnect_pending_off (tc);
1105 session_transport_closing_notify (&tc->connection);
1107 _vec_len (wrk->pending_disconnects) = 0;
1110 if (vec_len (wrk->pending_resets))
1112 thread_index = wrk->vm->thread_index;
1113 pending_resets = wrk->pending_resets;
1114 for (i = 0; i < vec_len (pending_resets); i++)
1116 tc = tcp_connection_get (pending_resets[i], thread_index);
1117 tcp_disconnect_pending_off (tc);
1118 tcp_handle_rst (tc);
1120 _vec_len (wrk->pending_resets) = 0;
1125 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1128 /* Reject out-of-order fins */
1129 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1132 /* Account for the FIN and send ack */
1134 tc->flags |= TCP_CONN_FINRCVD;
1135 tcp_program_ack (tc);
1136 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1137 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1138 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1139 tcp_program_disconnect (wrk, tc);
1140 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1141 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1142 *error = TCP_ERROR_FIN_RCVD;
1145 /** Enqueue data for delivery to application */
1147 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1150 int written, error = TCP_ERROR_ENQUEUED;
1152 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1154 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1155 1 /* queue event */ , 1);
1156 tc->bytes_in += written;
1158 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1160 /* Update rcv_nxt */
1161 if (PREDICT_TRUE (written == data_len))
1163 tc->rcv_nxt += written;
1165 /* If more data written than expected, account for out-of-order bytes. */
1166 else if (written > data_len)
1168 tc->rcv_nxt += written;
1169 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1171 else if (written > 0)
1173 /* We've written something but FIFO is probably full now */
1174 tc->rcv_nxt += written;
1175 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1179 /* Packet made it through for ack processing */
1180 if (tc->rcv_wnd < tc->snd_mss)
1181 return TCP_ERROR_ZERO_RWND;
1183 return TCP_ERROR_FIFO_FULL;
1186 /* Update SACK list if need be */
1187 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1189 /* Remove SACK blocks that have been delivered */
1190 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1196 /** Enqueue out-of-order data */
1198 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1204 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1207 /* Enqueue out-of-order data with relative offset */
1208 rv = session_enqueue_stream_connection (&tc->connection, b,
1209 vnet_buffer (b)->tcp.seq_number -
1210 tc->rcv_nxt, 0 /* queue event */ ,
1213 /* Nothing written */
1216 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1217 return TCP_ERROR_FIFO_FULL;
1220 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1221 tc->bytes_in += data_len;
1223 /* Update SACK list if in use */
1224 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1226 ooo_segment_t *newest;
1229 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1231 /* Get the newest segment from the fifo */
1232 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1235 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1236 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1237 start = tc->rcv_nxt + offset;
1238 end = start + ooo_segment_length (s0->rx_fifo, newest);
1239 tcp_update_sack_list (tc, start, end);
1240 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1241 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1245 return TCP_ERROR_ENQUEUED_OOO;
1249 * Check if ACK could be delayed. If ack can be delayed, it should return
1250 * true for a full frame. If we're always acking return 0.
1253 tcp_can_delack (tcp_connection_t * tc)
1255 /* Send ack if ... */
1257 /* just sent a rcv wnd 0
1258 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1259 /* constrained to send ack */
1260 || (tc->flags & TCP_CONN_SNDACK) != 0
1261 /* we're almost out of tx wnd */
1262 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1269 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1271 u32 discard, first = b->current_length;
1272 vlib_main_t *vm = vlib_get_main ();
1274 /* Handle multi-buffer segments */
1275 if (n_bytes_to_drop > b->current_length)
1277 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1281 discard = clib_min (n_bytes_to_drop, b->current_length);
1282 vlib_buffer_advance (b, discard);
1283 b = vlib_get_buffer (vm, b->next_buffer);
1284 n_bytes_to_drop -= discard;
1286 while (n_bytes_to_drop);
1287 if (n_bytes_to_drop > first)
1288 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1291 vlib_buffer_advance (b, n_bytes_to_drop);
1292 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1297 * Receive buffer for connection and handle acks
1299 * It handles both in order or out-of-order data.
1302 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1305 u32 error, n_bytes_to_drop, n_data_bytes;
1307 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1308 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1309 ASSERT (n_data_bytes);
1310 tc->data_segs_in += 1;
1312 /* Handle out-of-order data */
1313 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1315 /* Old sequence numbers allowed through because they overlapped
1317 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1319 /* Completely in the past (possible retransmit). Ack
1320 * retransmissions since we may not have any data to send */
1321 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1323 tcp_program_dupack (tc);
1324 tc->errors.below_data_wnd++;
1325 error = TCP_ERROR_SEGMENT_OLD;
1329 /* Chop off the bytes in the past and see if what is left
1330 * can be enqueued in order */
1331 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1332 n_data_bytes -= n_bytes_to_drop;
1333 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1334 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1336 error = TCP_ERROR_SEGMENT_OLD;
1342 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1343 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1344 tcp_program_dupack (tc);
1345 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1346 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1347 tc->rcv_las + tc->rcv_wnd);
1353 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1354 * segments can be enqueued after fifo tail offset changes. */
1355 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1356 if (tcp_can_delack (tc))
1358 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1359 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
1363 tcp_program_ack (tc);
1371 tcp_header_t tcp_header;
1372 tcp_connection_t tcp_connection;
1376 format_tcp_rx_trace (u8 * s, va_list * args)
1378 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1379 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1380 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1381 tcp_connection_t *tc = &t->tcp_connection;
1382 u32 indent = format_get_indent (s);
1384 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1385 format_tcp_state, tc->state, format_white_space, indent,
1386 format_tcp_header, &t->tcp_header, 128);
1392 format_tcp_rx_trace_short (u8 * s, va_list * args)
1394 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1395 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1396 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1398 s = format (s, "%d -> %d (%U)",
1399 clib_net_to_host_u16 (t->tcp_header.dst_port),
1400 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1401 t->tcp_connection.state);
1407 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1408 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1412 clib_memcpy_fast (&t0->tcp_connection, tc0,
1413 sizeof (t0->tcp_connection));
1417 th0 = tcp_buffer_hdr (b0);
1419 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1423 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1424 vlib_frame_t * frame, u8 is_ip4)
1428 n_left = frame->n_vectors;
1429 from = vlib_frame_vector_args (frame);
1433 tcp_connection_t *tc0;
1440 b0 = vlib_get_buffer (vm, bi0);
1442 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1444 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1445 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1447 th0 = tcp_buffer_hdr (b0);
1448 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1457 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1458 u8 is_ip4, u32 evt, u32 val)
1461 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1463 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1466 #define tcp_maybe_inc_counter(node_id, err, count) \
1468 if (next0 != tcp_next_drop (is_ip4)) \
1469 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1470 tcp6_##node_id##_node.index, is_ip4, err, \
1473 #define tcp_inc_counter(node_id, err, count) \
1474 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1475 tcp6_##node_id##_node.index, is_ip4, \
1477 #define tcp_maybe_inc_err_counter(cnts, err) \
1479 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1481 #define tcp_inc_err_counter(cnts, err, val) \
1485 #define tcp_store_err_counters(node_id, cnts) \
1488 for (i = 0; i < TCP_N_ERROR; i++) \
1490 tcp_inc_counter(node_id, i, cnts[i]); \
1495 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1496 vlib_frame_t * frame, int is_ip4)
1498 u32 thread_index = vm->thread_index, errors = 0;
1499 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1500 u32 n_left_from, *from, *first_buffer;
1501 u16 err_counters[TCP_N_ERROR] = { 0 };
1503 if (node->flags & VLIB_NODE_FLAG_TRACE)
1504 tcp_established_trace_frame (vm, node, frame, is_ip4);
1506 first_buffer = from = vlib_frame_vector_args (frame);
1507 n_left_from = frame->n_vectors;
1509 while (n_left_from > 0)
1511 u32 bi0, error0 = TCP_ERROR_ACK_OK;
1514 tcp_connection_t *tc0;
1516 if (n_left_from > 1)
1519 pb = vlib_get_buffer (vm, from[1]);
1520 vlib_prefetch_buffer_header (pb, LOAD);
1521 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1528 b0 = vlib_get_buffer (vm, bi0);
1529 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1532 if (PREDICT_FALSE (tc0 == 0))
1534 error0 = TCP_ERROR_INVALID_CONNECTION;
1538 th0 = tcp_buffer_hdr (b0);
1540 /* TODO header prediction fast path */
1542 /* 1-4: check SEQ, RST, SYN */
1543 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
1545 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
1549 /* 5: check the ACK field */
1550 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
1553 /* 6: check the URG bit TODO */
1555 /* 7: process the segment text */
1556 if (vnet_buffer (b0)->tcp.data_len)
1557 error0 = tcp_segment_rcv (wrk, tc0, b0);
1559 /* 8: check the FIN bit */
1560 if (PREDICT_FALSE (tcp_is_fin (th0)))
1561 tcp_rcv_fin (wrk, tc0, b0, &error0);
1564 tcp_inc_err_counter (err_counters, error0, 1);
1567 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1569 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1570 tcp_store_err_counters (established, err_counters);
1571 tcp_handle_postponed_dequeues (wrk);
1572 tcp_handle_disconnects (wrk);
1573 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
1575 return frame->n_vectors;
1578 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1579 vlib_node_runtime_t * node,
1580 vlib_frame_t * from_frame)
1582 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1585 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1586 vlib_node_runtime_t * node,
1587 vlib_frame_t * from_frame)
1589 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1593 VLIB_REGISTER_NODE (tcp4_established_node) =
1595 .name = "tcp4-established",
1596 /* Takes a vector of packets. */
1597 .vector_size = sizeof (u32),
1598 .n_errors = TCP_N_ERROR,
1599 .error_strings = tcp_error_strings,
1600 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1603 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1604 foreach_tcp_state_next
1607 .format_trace = format_tcp_rx_trace_short,
1612 VLIB_REGISTER_NODE (tcp6_established_node) =
1614 .name = "tcp6-established",
1615 /* Takes a vector of packets. */
1616 .vector_size = sizeof (u32),
1617 .n_errors = TCP_N_ERROR,
1618 .error_strings = tcp_error_strings,
1619 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1622 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1623 foreach_tcp_state_next
1626 .format_trace = format_tcp_rx_trace_short,
1632 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1635 transport_connection_t *tmp = 0;
1642 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1645 u8 is_ip_valid = 0, val_l, val_r;
1647 if (tc->connection.is_ip4)
1649 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1651 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1652 &tc->connection.lcl_ip.ip4);
1653 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1654 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1655 &tc->connection.rmt_ip.ip4);
1656 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1657 is_ip_valid = val_l && val_r;
1661 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1663 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1664 &tc->connection.lcl_ip.ip6);
1665 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1666 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1667 &tc->connection.rmt_ip.ip6);
1668 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1669 is_ip_valid = val_l && val_r;
1672 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1673 && (tc->state == TCP_STATE_LISTEN
1674 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1678 handle = session_lookup_half_open_handle (&tc->connection);
1679 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1680 tc->c_proto, tc->c_is_ip4);
1684 if (tmp->lcl_port == hdr->dst_port
1685 && tmp->rmt_port == hdr->src_port)
1687 TCP_DBG ("half-open is valid!");
1696 * Lookup transport connection
1698 static tcp_connection_t *
1699 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1703 transport_connection_t *tconn;
1704 tcp_connection_t *tc;
1709 ip4 = vlib_buffer_get_current (b);
1710 tcp = ip4_next_header (ip4);
1711 tconn = session_lookup_connection_wt4 (fib_index,
1716 TRANSPORT_PROTO_TCP,
1717 thread_index, &is_filtered);
1718 tc = tcp_get_connection_from_transport (tconn);
1719 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1724 ip6 = vlib_buffer_get_current (b);
1725 tcp = ip6_next_header (ip6);
1726 tconn = session_lookup_connection_wt6 (fib_index,
1731 TRANSPORT_PROTO_TCP,
1732 thread_index, &is_filtered);
1733 tc = tcp_get_connection_from_transport (tconn);
1734 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1739 static tcp_connection_t *
1740 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1746 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1747 tcp_header_t *tcp = tcp_buffer_hdr (b);
1748 s = session_lookup_listener4 (fib_index,
1750 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1754 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1755 tcp_header_t *tcp = tcp_buffer_hdr (b);
1756 s = session_lookup_listener6 (fib_index,
1758 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1761 if (PREDICT_TRUE (s != 0))
1762 return tcp_get_connection_from_transport (transport_get_listener
1763 (TRANSPORT_PROTO_TCP,
1764 s->connection_index));
1770 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1772 vnet_main_t *vnm = vnet_get_main ();
1773 const dpo_id_t *dpo;
1774 const load_balance_t *lb;
1775 vnet_hw_interface_t *hw_if;
1776 u32 sw_if_idx, lb_idx;
1780 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1781 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1785 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1786 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1789 lb = load_balance_get (lb_idx);
1790 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1792 dpo = load_balance_get_bucket_i (lb, 0);
1794 sw_if_idx = dpo_get_urpf (dpo);
1795 if (PREDICT_FALSE (sw_if_idx == ~0))
1798 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1799 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
1800 tc->cfg_flags |= TCP_CFG_F_TSO;
1804 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1805 vlib_frame_t * from_frame, int is_ip4)
1807 u32 n_left_from, *from, *first_buffer, errors = 0;
1808 u32 my_thread_index = vm->thread_index;
1809 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
1811 from = first_buffer = vlib_frame_vector_args (from_frame);
1812 n_left_from = from_frame->n_vectors;
1814 while (n_left_from > 0)
1816 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
1817 tcp_connection_t *tc0, *new_tc0;
1818 tcp_header_t *tcp0 = 0;
1826 b0 = vlib_get_buffer (vm, bi0);
1828 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
1829 if (PREDICT_FALSE (tc0 == 0))
1831 error0 = TCP_ERROR_INVALID_CONNECTION;
1835 /* Half-open completed recently but the connection was't removed
1836 * yet by the owning thread */
1837 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1839 /* Make sure the connection actually exists */
1840 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
1841 my_thread_index, is_ip4));
1842 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
1846 ack0 = vnet_buffer (b0)->tcp.ack_number;
1847 seq0 = vnet_buffer (b0)->tcp.seq_number;
1848 tcp0 = tcp_buffer_hdr (b0);
1850 /* Crude check to see if the connection handle does not match
1851 * the packet. Probably connection just switched to established */
1852 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1853 || tcp0->src_port != tc0->c_rmt_port))
1855 error0 = TCP_ERROR_INVALID_CONNECTION;
1859 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
1860 && !tcp_syn (tcp0)))
1862 error0 = TCP_ERROR_SEGMENT_INVALID;
1866 /* SYNs consume sequence numbers */
1867 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
1870 * 1. check the ACK bit
1874 * If the ACK bit is set
1875 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1876 * the RST bit is set, if so drop the segment and return)
1877 * <SEQ=SEG.ACK><CTL=RST>
1878 * and discard the segment. Return.
1879 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1883 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
1885 if (!tcp_rst (tcp0))
1886 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1887 error0 = TCP_ERROR_RCV_WND;
1891 /* Make sure ACK is valid */
1892 if (seq_gt (tc0->snd_una, ack0))
1894 error0 = TCP_ERROR_ACK_INVALID;
1900 * 2. check the RST bit
1905 /* If ACK is acceptable, signal client that peer is not
1906 * willing to accept connection and drop connection*/
1908 tcp_rcv_rst (wrk, tc0);
1909 error0 = TCP_ERROR_RST_RCVD;
1914 * 3. check the security and precedence (skipped)
1918 * 4. check the SYN bit
1921 /* No SYN flag. Drop. */
1922 if (!tcp_syn (tcp0))
1924 error0 = TCP_ERROR_SEGMENT_INVALID;
1929 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
1931 error0 = TCP_ERROR_OPTIONS;
1935 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1936 * current thread pool. */
1937 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
1938 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
1939 new_tc0->irs = seq0;
1940 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1941 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1943 /* If this is not the owning thread, wait for syn retransmit to
1944 * expire and cleanup then */
1945 if (tcp_half_open_connection_cleanup (tc0))
1946 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
1948 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
1950 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
1951 new_tc0->tsval_recent_age = tcp_time_now ();
1954 if (tcp_opts_wscale (&new_tc0->rcv_opts))
1955 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
1957 new_tc0->rcv_wscale = 0;
1959 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
1960 << new_tc0->snd_wscale;
1961 new_tc0->snd_wl1 = seq0;
1962 new_tc0->snd_wl2 = ack0;
1964 tcp_connection_init_vars (new_tc0);
1966 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1967 if (PREDICT_TRUE (tcp_ack (tcp0)))
1969 /* Our SYN is ACKed: we have iss < ack = snd_una */
1971 /* TODO Dequeue acknowledged segments if we support Fast Open */
1972 new_tc0->snd_una = ack0;
1973 new_tc0->state = TCP_STATE_ESTABLISHED;
1975 /* Make sure las is initialized for the wnd computation */
1976 new_tc0->rcv_las = new_tc0->rcv_nxt;
1978 /* Notify app that we have connection. If session layer can't
1979 * allocate session send reset */
1980 if (session_stream_connect_notify (&new_tc0->connection, 0))
1982 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
1983 tcp_connection_cleanup (new_tc0);
1984 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1988 new_tc0->tx_fifo_size =
1989 transport_tx_fifo_size (&new_tc0->connection);
1990 /* Update rtt with the syn-ack sample */
1991 tcp_estimate_initial_rtt (new_tc0);
1992 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
1993 error0 = TCP_ERROR_SYN_ACKS_RCVD;
1995 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1998 new_tc0->state = TCP_STATE_SYN_RCVD;
2000 /* Notify app that we have connection */
2001 if (session_stream_connect_notify (&new_tc0->connection, 0))
2003 tcp_connection_cleanup (new_tc0);
2004 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2005 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2006 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2010 new_tc0->tx_fifo_size =
2011 transport_tx_fifo_size (&new_tc0->connection);
2012 new_tc0->rtt_ts = 0;
2013 tcp_init_snd_vars (new_tc0);
2014 tcp_send_synack (new_tc0);
2015 error0 = TCP_ERROR_SYNS_RCVD;
2019 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2020 tcp_check_tx_offload (new_tc0, is_ip4);
2022 /* Read data, if any */
2023 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2025 clib_warning ("rcvd data in syn-sent");
2026 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2027 if (error0 == TCP_ERROR_ACK_OK)
2028 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2032 /* Send ack now instead of programming it because connection was
2033 * just established and it's not optional. */
2034 tcp_send_ack (new_tc0);
2039 tcp_inc_counter (syn_sent, error0, 1);
2040 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2042 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2043 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2044 clib_memcpy_fast (&t0->tcp_connection, tc0,
2045 sizeof (t0->tcp_connection));
2049 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2051 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2052 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2053 tcp_handle_disconnects (wrk);
2055 return from_frame->n_vectors;
2058 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2059 vlib_node_runtime_t * node,
2060 vlib_frame_t * from_frame)
2062 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2065 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2066 vlib_node_runtime_t * node,
2067 vlib_frame_t * from_frame)
2069 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2073 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2075 .name = "tcp4-syn-sent",
2076 /* Takes a vector of packets. */
2077 .vector_size = sizeof (u32),
2078 .n_errors = TCP_N_ERROR,
2079 .error_strings = tcp_error_strings,
2080 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2083 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2084 foreach_tcp_state_next
2087 .format_trace = format_tcp_rx_trace_short,
2092 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2094 .name = "tcp6-syn-sent",
2095 /* Takes a vector of packets. */
2096 .vector_size = sizeof (u32),
2097 .n_errors = TCP_N_ERROR,
2098 .error_strings = tcp_error_strings,
2099 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2102 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2103 foreach_tcp_state_next
2106 .format_trace = format_tcp_rx_trace_short,
2111 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2112 * as per RFC793 p. 64
2115 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2116 vlib_frame_t * from_frame, int is_ip4)
2118 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2119 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2120 u32 n_left_from, *from, max_dequeue;
2122 from = first_buffer = vlib_frame_vector_args (from_frame);
2123 n_left_from = from_frame->n_vectors;
2125 while (n_left_from > 0)
2127 u32 bi0, error0 = TCP_ERROR_NONE;
2128 tcp_header_t *tcp0 = 0;
2129 tcp_connection_t *tc0;
2137 b0 = vlib_get_buffer (vm, bi0);
2138 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2140 if (PREDICT_FALSE (tc0 == 0))
2142 error0 = TCP_ERROR_INVALID_CONNECTION;
2146 tcp0 = tcp_buffer_hdr (b0);
2147 is_fin0 = tcp_is_fin (tcp0);
2151 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2153 tcp_connection_t *tmp;
2154 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2156 if (tmp->state != tc0->state)
2158 if (tc0->state != TCP_STATE_CLOSED)
2159 clib_warning ("state changed");
2166 * Special treatment for CLOSED
2168 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2170 error0 = TCP_ERROR_CONNECTION_CLOSED;
2175 * For all other states (except LISTEN)
2178 /* 1-4: check SEQ, RST, SYN */
2179 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2182 /* 5: check the ACK field */
2185 case TCP_STATE_SYN_RCVD:
2187 /* Make sure the segment is exactly right */
2188 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2190 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2191 error0 = TCP_ERROR_SEGMENT_INVALID;
2196 * If the segment acknowledgment is not acceptable, form a
2198 * <SEQ=SEG.ACK><CTL=RST>
2201 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2203 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2204 error0 = TCP_ERROR_SEGMENT_INVALID;
2208 /* Update rtt and rto */
2209 tcp_estimate_initial_rtt (tc0);
2210 tcp_connection_tx_pacer_update (tc0);
2212 /* Switch state to ESTABLISHED */
2213 tc0->state = TCP_STATE_ESTABLISHED;
2214 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2216 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2217 tcp_check_tx_offload (tc0, is_ip4);
2219 /* Initialize session variables */
2220 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2221 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2222 << tc0->rcv_opts.wscale;
2223 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2224 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2226 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2227 tcp_retransmit_timer_reset (tc0);
2228 if (session_stream_accept_notify (&tc0->connection))
2230 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2231 tcp_send_reset (tc0);
2232 session_transport_delete_notify (&tc0->connection);
2233 tcp_connection_cleanup (tc0);
2236 error0 = TCP_ERROR_ACK_OK;
2238 case TCP_STATE_ESTABLISHED:
2239 /* We can get packets in established state here because they
2240 * were enqueued before state change */
2241 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2245 case TCP_STATE_FIN_WAIT_1:
2246 /* In addition to the processing for the ESTABLISHED state, if
2247 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2248 * continue processing in that state. */
2249 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2252 /* Still have to send the FIN */
2253 if (tc0->flags & TCP_CONN_FINPNDG)
2255 /* TX fifo finally drained */
2256 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2257 if (max_dequeue <= tc0->burst_acked)
2259 /* If a fin was received and data was acked extend wait */
2260 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2261 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2262 tcp_cfg.closewait_time);
2264 /* If FIN is ACKed */
2265 else if (tc0->snd_una == tc0->snd_nxt)
2267 /* Stop all retransmit timers because we have nothing more
2269 tcp_connection_timers_reset (tc0);
2271 /* We already have a FIN but didn't transition to CLOSING
2272 * because of outstanding tx data. Close the connection. */
2273 if (tc0->flags & TCP_CONN_FINRCVD)
2275 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2276 session_transport_closed_notify (&tc0->connection);
2277 tcp_program_cleanup (wrk, tc0);
2281 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2282 /* Enable waitclose because we're willing to wait for peer's
2283 * FIN but not indefinitely. */
2284 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2286 /* Don't try to deq the FIN acked */
2287 if (tc0->burst_acked > 1)
2288 session_tx_fifo_dequeue_drop (&tc0->connection,
2289 tc0->burst_acked - 1);
2290 tc0->burst_acked = 0;
2293 case TCP_STATE_FIN_WAIT_2:
2294 /* In addition to the processing for the ESTABLISHED state, if
2295 * the retransmission queue is empty, the user's CLOSE can be
2296 * acknowledged ("ok") but do not delete the TCB. */
2297 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2299 tc0->burst_acked = 0;
2301 case TCP_STATE_CLOSE_WAIT:
2302 /* Do the same processing as for the ESTABLISHED state. */
2303 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2306 if (!(tc0->flags & TCP_CONN_FINPNDG))
2309 /* Still have outstanding tx data */
2310 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2311 if (max_dequeue > tc0->burst_acked)
2315 tcp_connection_timers_reset (tc0);
2316 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2317 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2319 case TCP_STATE_CLOSING:
2320 /* In addition to the processing for the ESTABLISHED state, if
2321 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2322 * otherwise ignore the segment. */
2323 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2326 if (tc0->snd_una != tc0->snd_nxt)
2329 tcp_connection_timers_reset (tc0);
2330 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2331 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2332 session_transport_closed_notify (&tc0->connection);
2336 case TCP_STATE_LAST_ACK:
2337 /* The only thing that [should] arrive in this state is an
2338 * acknowledgment of our FIN. If our FIN is now acknowledged,
2339 * delete the TCB, enter the CLOSED state, and return. */
2341 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2344 /* Apparently our ACK for the peer's FIN was lost */
2345 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2351 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2352 session_transport_closed_notify (&tc0->connection);
2354 /* Don't free the connection from the data path since
2355 * we can't ensure that we have no packets already enqueued
2356 * to output. Rely instead on the waitclose timer */
2357 tcp_connection_timers_reset (tc0);
2358 tcp_program_cleanup (tcp_get_worker (tc0->c_thread_index), tc0);
2363 case TCP_STATE_TIME_WAIT:
2364 /* The only thing that can arrive in this state is a
2365 * retransmission of the remote FIN. Acknowledge it, and restart
2366 * the 2 MSL timeout. */
2368 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2374 tcp_program_ack (tc0);
2375 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2383 /* 6: check the URG bit TODO */
2385 /* 7: process the segment text */
2388 case TCP_STATE_ESTABLISHED:
2389 case TCP_STATE_FIN_WAIT_1:
2390 case TCP_STATE_FIN_WAIT_2:
2391 if (vnet_buffer (b0)->tcp.data_len)
2392 error0 = tcp_segment_rcv (wrk, tc0, b0);
2394 case TCP_STATE_CLOSE_WAIT:
2395 case TCP_STATE_CLOSING:
2396 case TCP_STATE_LAST_ACK:
2397 case TCP_STATE_TIME_WAIT:
2398 /* This should not occur, since a FIN has been received from the
2399 * remote side. Ignore the segment text. */
2403 /* 8: check the FIN bit */
2407 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
2411 case TCP_STATE_ESTABLISHED:
2412 /* Account for the FIN and send ack */
2414 tcp_program_ack (tc0);
2415 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
2416 tcp_program_disconnect (wrk, tc0);
2417 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, 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 (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2429 case TCP_STATE_CLOSE_WAIT:
2430 case TCP_STATE_CLOSING:
2431 case TCP_STATE_LAST_ACK:
2434 case TCP_STATE_FIN_WAIT_1:
2437 if (tc0->flags & TCP_CONN_FINPNDG)
2439 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2440 * sending it. Since we already received a fin, do not wait
2442 tc0->flags |= TCP_CONN_FINRCVD;
2443 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2444 tcp_cfg.closewait_time);
2448 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2449 tcp_program_ack (tc0);
2450 /* Wait for ACK for our FIN but not forever */
2451 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2452 tcp_cfg.closing_time);
2455 case TCP_STATE_FIN_WAIT_2:
2456 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2458 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2459 tcp_connection_timers_reset (tc0);
2460 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2461 tcp_program_ack (tc0);
2462 session_transport_closed_notify (&tc0->connection);
2464 case TCP_STATE_TIME_WAIT:
2465 /* Remain in the TIME-WAIT state. Restart the time-wait
2468 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2471 error0 = TCP_ERROR_FIN_RCVD;
2475 tcp_inc_counter (rcv_process, error0, 1);
2476 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2478 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2479 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2483 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2485 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2486 tcp_handle_postponed_dequeues (wrk);
2487 tcp_handle_disconnects (wrk);
2488 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2490 return from_frame->n_vectors;
2493 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2494 vlib_node_runtime_t * node,
2495 vlib_frame_t * from_frame)
2497 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2500 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2501 vlib_node_runtime_t * node,
2502 vlib_frame_t * from_frame)
2504 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2508 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2510 .name = "tcp4-rcv-process",
2511 /* Takes a vector of packets. */
2512 .vector_size = sizeof (u32),
2513 .n_errors = TCP_N_ERROR,
2514 .error_strings = tcp_error_strings,
2515 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2518 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2519 foreach_tcp_state_next
2522 .format_trace = format_tcp_rx_trace_short,
2527 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2529 .name = "tcp6-rcv-process",
2530 /* Takes a vector of packets. */
2531 .vector_size = sizeof (u32),
2532 .n_errors = TCP_N_ERROR,
2533 .error_strings = tcp_error_strings,
2534 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2537 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2538 foreach_tcp_state_next
2541 .format_trace = format_tcp_rx_trace_short,
2546 * LISTEN state processing as per RFC 793 p. 65
2549 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2550 vlib_frame_t * from_frame, int is_ip4)
2552 u32 n_left_from, *from, n_syns = 0, *first_buffer;
2553 u32 thread_index = vm->thread_index;
2555 from = first_buffer = vlib_frame_vector_args (from_frame);
2556 n_left_from = from_frame->n_vectors;
2558 while (n_left_from > 0)
2560 u32 bi, error = TCP_ERROR_NONE;
2561 tcp_connection_t *lc, *child;
2568 b = vlib_get_buffer (vm, bi);
2570 lc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2571 if (PREDICT_FALSE (lc == 0))
2573 tcp_connection_t *tc;
2574 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2576 if (tc->state != TCP_STATE_TIME_WAIT)
2578 error = TCP_ERROR_CREATE_EXISTS;
2581 lc = tcp_lookup_listener (b, tc->c_fib_index, is_ip4);
2582 /* clean up the old session */
2583 tcp_connection_del (tc);
2586 /* Make sure connection wasn't just created */
2587 child = tcp_lookup_connection (lc->c_fib_index, b, thread_index,
2589 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2591 error = TCP_ERROR_CREATE_EXISTS;
2595 /* Create child session. For syn-flood protection use filter */
2597 /* 1. first check for an RST: handled in dispatch */
2598 /* if (tcp_rst (th0))
2602 /* 2. second check for an ACK: handled in dispatch */
2603 /* if (tcp_ack (th0))
2605 tcp_send_reset (b0, is_ip4);
2610 /* 3. check for a SYN (did that already) */
2612 /* Create child session and send SYN-ACK */
2613 child = tcp_connection_alloc (thread_index);
2615 if (tcp_options_parse (tcp_buffer_hdr (b), &child->rcv_opts, 1))
2617 error = TCP_ERROR_OPTIONS;
2618 tcp_connection_free (child);
2622 tcp_init_w_buffer (child, b, is_ip4);
2624 child->state = TCP_STATE_SYN_RCVD;
2625 child->c_fib_index = lc->c_fib_index;
2626 child->cc_algo = lc->cc_algo;
2627 tcp_connection_init_vars (child);
2628 child->rto = TCP_RTO_MIN;
2630 if (session_stream_accept (&child->connection, lc->c_s_index,
2631 lc->c_thread_index, 0 /* notify */ ))
2633 tcp_connection_cleanup (child);
2634 error = TCP_ERROR_CREATE_SESSION_FAIL;
2638 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2640 tcp_send_synack (child);
2642 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2646 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
2649 t = vlib_add_trace (vm, node, b, sizeof (*t));
2650 clib_memcpy_fast (&t->tcp_header, tcp_buffer_hdr (b),
2651 sizeof (t->tcp_header));
2652 clib_memcpy_fast (&t->tcp_connection, lc,
2653 sizeof (t->tcp_connection));
2656 n_syns += (error == TCP_ERROR_NONE);
2659 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2660 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2662 return from_frame->n_vectors;
2665 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2666 vlib_frame_t * from_frame)
2668 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2671 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2672 vlib_frame_t * from_frame)
2674 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2678 VLIB_REGISTER_NODE (tcp4_listen_node) =
2680 .name = "tcp4-listen",
2681 /* Takes a vector of packets. */
2682 .vector_size = sizeof (u32),
2683 .n_errors = TCP_N_ERROR,
2684 .error_strings = tcp_error_strings,
2685 .n_next_nodes = TCP_LISTEN_N_NEXT,
2688 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2689 foreach_tcp_state_next
2692 .format_trace = format_tcp_rx_trace_short,
2697 VLIB_REGISTER_NODE (tcp6_listen_node) =
2699 .name = "tcp6-listen",
2700 /* Takes a vector of packets. */
2701 .vector_size = sizeof (u32),
2702 .n_errors = TCP_N_ERROR,
2703 .error_strings = tcp_error_strings,
2704 .n_next_nodes = TCP_LISTEN_N_NEXT,
2707 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2708 foreach_tcp_state_next
2711 .format_trace = format_tcp_rx_trace_short,
2715 typedef enum _tcp_input_next
2717 TCP_INPUT_NEXT_DROP,
2718 TCP_INPUT_NEXT_LISTEN,
2719 TCP_INPUT_NEXT_RCV_PROCESS,
2720 TCP_INPUT_NEXT_SYN_SENT,
2721 TCP_INPUT_NEXT_ESTABLISHED,
2722 TCP_INPUT_NEXT_RESET,
2723 TCP_INPUT_NEXT_PUNT,
2727 #define foreach_tcp4_input_next \
2728 _ (DROP, "ip4-drop") \
2729 _ (LISTEN, "tcp4-listen") \
2730 _ (RCV_PROCESS, "tcp4-rcv-process") \
2731 _ (SYN_SENT, "tcp4-syn-sent") \
2732 _ (ESTABLISHED, "tcp4-established") \
2733 _ (RESET, "tcp4-reset") \
2734 _ (PUNT, "ip4-punt")
2736 #define foreach_tcp6_input_next \
2737 _ (DROP, "ip6-drop") \
2738 _ (LISTEN, "tcp6-listen") \
2739 _ (RCV_PROCESS, "tcp6-rcv-process") \
2740 _ (SYN_SENT, "tcp6-syn-sent") \
2741 _ (ESTABLISHED, "tcp6-established") \
2742 _ (RESET, "tcp6-reset") \
2743 _ (PUNT, "ip6-punt")
2745 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2748 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2749 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2751 tcp_connection_t *tc;
2756 for (i = 0; i < n_bufs; i++)
2758 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2760 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2761 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2763 tcp = vlib_buffer_get_current (bs[i]);
2764 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2770 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2772 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2774 *next = TCP_INPUT_NEXT_DROP;
2776 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2778 *next = TCP_INPUT_NEXT_PUNT;
2779 *error = TCP_ERROR_PUNT;
2783 *next = TCP_INPUT_NEXT_RESET;
2784 *error = TCP_ERROR_NO_LISTENER;
2789 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2790 vlib_buffer_t * b, u16 * next,
2791 vlib_node_runtime_t * error_node)
2797 tcp = tcp_buffer_hdr (b);
2798 flags = tcp->flags & filter_flags;
2799 *next = tm->dispatch_table[tc->state][flags].next;
2800 error = tm->dispatch_table[tc->state][flags].error;
2803 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2805 b->error = error_node->errors[error];
2806 if (error == TCP_ERROR_DISPATCH)
2807 clib_warning ("tcp conn %u disp error state %U flags %U",
2808 tc->c_c_index, format_tcp_state, tc->state,
2809 format_tcp_flags, (int) flags);
2814 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2815 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2817 u32 n_left_from, *from, thread_index = vm->thread_index;
2818 tcp_main_t *tm = vnet_get_tcp_main ();
2819 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2820 u16 nexts[VLIB_FRAME_SIZE], *next;
2821 vlib_node_runtime_t *error_node;
2823 tcp_set_time_now (tcp_get_worker (thread_index));
2825 error_node = vlib_node_get_runtime (vm, tcp_node_index (input, is_ip4));
2826 from = vlib_frame_vector_args (frame);
2827 n_left_from = frame->n_vectors;
2828 vlib_get_buffers (vm, from, bufs, n_left_from);
2833 while (n_left_from >= 4)
2835 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2836 tcp_connection_t *tc0, *tc1;
2839 vlib_prefetch_buffer_header (b[2], STORE);
2840 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2842 vlib_prefetch_buffer_header (b[3], STORE);
2843 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2846 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2848 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2850 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2853 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2855 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2856 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2858 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2859 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2861 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], error_node);
2862 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], error_node);
2866 if (PREDICT_TRUE (tc0 != 0))
2868 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2869 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2870 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], error_node);
2874 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2875 b[0]->error = error_node->errors[error0];
2878 if (PREDICT_TRUE (tc1 != 0))
2880 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2881 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2882 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], error_node);
2886 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2887 b[1]->error = error_node->errors[error1];
2895 while (n_left_from > 0)
2897 tcp_connection_t *tc0;
2898 u32 error0 = TCP_ERROR_NO_LISTENER;
2900 if (n_left_from > 1)
2902 vlib_prefetch_buffer_header (b[1], STORE);
2903 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2906 next[0] = TCP_INPUT_NEXT_DROP;
2907 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2909 if (PREDICT_TRUE (tc0 != 0))
2911 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2912 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2913 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], error_node);
2917 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2918 b[0]->error = error_node->errors[error0];
2926 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2927 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2929 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2930 return frame->n_vectors;
2933 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2934 vlib_node_runtime_t * node,
2935 vlib_frame_t * from_frame)
2937 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2938 1 /* is_nolookup */ );
2941 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2942 vlib_node_runtime_t * node,
2943 vlib_frame_t * from_frame)
2945 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2946 1 /* is_nolookup */ );
2950 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2952 .name = "tcp4-input-nolookup",
2953 /* Takes a vector of packets. */
2954 .vector_size = sizeof (u32),
2955 .n_errors = TCP_N_ERROR,
2956 .error_strings = tcp_error_strings,
2957 .n_next_nodes = TCP_INPUT_N_NEXT,
2960 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2961 foreach_tcp4_input_next
2964 .format_buffer = format_tcp_header,
2965 .format_trace = format_tcp_rx_trace,
2970 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2972 .name = "tcp6-input-nolookup",
2973 /* Takes a vector of packets. */
2974 .vector_size = sizeof (u32),
2975 .n_errors = TCP_N_ERROR,
2976 .error_strings = tcp_error_strings,
2977 .n_next_nodes = TCP_INPUT_N_NEXT,
2980 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2981 foreach_tcp6_input_next
2984 .format_buffer = format_tcp_header,
2985 .format_trace = format_tcp_rx_trace,
2989 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2990 vlib_frame_t * from_frame)
2992 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2993 0 /* is_nolookup */ );
2996 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2997 vlib_frame_t * from_frame)
2999 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3000 0 /* is_nolookup */ );
3004 VLIB_REGISTER_NODE (tcp4_input_node) =
3006 .name = "tcp4-input",
3007 /* Takes a vector of packets. */
3008 .vector_size = sizeof (u32),
3009 .n_errors = TCP_N_ERROR,
3010 .error_strings = tcp_error_strings,
3011 .n_next_nodes = TCP_INPUT_N_NEXT,
3014 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3015 foreach_tcp4_input_next
3018 .format_buffer = format_tcp_header,
3019 .format_trace = format_tcp_rx_trace,
3024 VLIB_REGISTER_NODE (tcp6_input_node) =
3026 .name = "tcp6-input",
3027 /* Takes a vector of packets. */
3028 .vector_size = sizeof (u32),
3029 .n_errors = TCP_N_ERROR,
3030 .error_strings = tcp_error_strings,
3031 .n_next_nodes = TCP_INPUT_N_NEXT,
3034 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3035 foreach_tcp6_input_next
3038 .format_buffer = format_tcp_header,
3039 .format_trace = format_tcp_rx_trace,
3043 #ifndef CLIB_MARCH_VARIANT
3045 tcp_dispatch_table_init (tcp_main_t * tm)
3048 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3049 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3051 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3052 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3055 #define _(t,f,n,e) \
3057 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3058 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3061 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3062 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3063 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3064 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3065 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3066 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3067 TCP_ERROR_ACK_INVALID);
3068 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3069 TCP_ERROR_SEGMENT_INVALID);
3070 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3071 TCP_ERROR_SEGMENT_INVALID);
3072 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3073 TCP_ERROR_INVALID_CONNECTION);
3074 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3075 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3076 TCP_ERROR_SEGMENT_INVALID);
3077 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3078 TCP_ERROR_SEGMENT_INVALID);
3079 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3080 TCP_ERROR_SEGMENT_INVALID);
3081 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3082 TCP_ERROR_SEGMENT_INVALID);
3083 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3084 TCP_ERROR_SEGMENT_INVALID);
3085 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3086 TCP_ERROR_SEGMENT_INVALID);
3087 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3088 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3089 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3090 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3091 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3092 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3094 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3095 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3097 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3099 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3100 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3101 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3102 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3104 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3106 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3107 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3108 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3110 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3111 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3112 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3113 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3114 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3115 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3116 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3117 /* SYN-ACK for a SYN */
3118 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3120 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3121 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3122 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3124 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3125 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3127 /* ACK for for established connection -> tcp-established. */
3128 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3129 /* FIN for for established connection -> tcp-established. */
3130 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3131 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3133 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3135 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3136 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3137 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3139 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3140 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3141 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3142 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3143 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3144 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3145 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3146 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3148 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3149 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3151 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3153 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3154 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3155 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3156 /* ACK or FIN-ACK to our FIN */
3157 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3158 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3160 /* FIN in reply to our FIN from the other side */
3161 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3162 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3163 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3165 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3166 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3167 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3168 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3169 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3170 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3171 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3173 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3174 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3175 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3176 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3178 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3180 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3181 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3182 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3183 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3185 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3186 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3187 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3188 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3190 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3192 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3193 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3194 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3195 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3197 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3198 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3200 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3202 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3203 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3204 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3206 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3207 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3208 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3209 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3210 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3211 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3212 /* FIN confirming that the peer (app) has closed */
3213 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3214 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3215 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3217 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3218 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3220 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3221 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3223 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3224 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3226 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3227 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3229 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3231 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3233 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3234 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3235 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3237 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3238 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3239 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3240 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3241 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3242 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3243 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3244 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3246 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3247 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3249 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3251 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3252 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3253 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3254 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3255 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3257 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3258 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3260 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3261 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3262 * incoming segment not containing a RST causes a RST to be sent in
3264 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3265 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3266 TCP_ERROR_CONNECTION_CLOSED);
3267 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3268 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3269 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3270 TCP_ERROR_CONNECTION_CLOSED);
3274 static clib_error_t *
3275 tcp_input_init (vlib_main_t * vm)
3277 clib_error_t *error = 0;
3278 tcp_main_t *tm = vnet_get_tcp_main ();
3280 if ((error = vlib_call_init_function (vm, tcp_init)))
3283 /* Initialize dispatch table. */
3284 tcp_dispatch_table_init (tm);
3289 VLIB_INIT_FUNCTION (tcp_input_init);
3291 #endif /* CLIB_MARCH_VARIANT */
3294 * fd.io coding-style-patch-verification: ON
3297 * eval: (c-set-style "gnu")