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 */
218 tc->rst_state = tc->state;
221 case TCP_STATE_ESTABLISHED:
222 tcp_connection_timers_reset (tc);
223 tcp_cong_recovery_off (tc);
224 tcp_program_reset_ntf (wrk, tc);
225 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
226 tcp_program_cleanup (wrk, tc);
228 case TCP_STATE_CLOSE_WAIT:
229 case TCP_STATE_FIN_WAIT_1:
230 case TCP_STATE_FIN_WAIT_2:
231 case TCP_STATE_CLOSING:
232 case TCP_STATE_LAST_ACK:
233 tcp_connection_timers_reset (tc);
234 tcp_cong_recovery_off (tc);
235 tcp_program_reset_ntf (wrk, tc);
236 /* Make sure we mark the session as closed. In some states we may
237 * be still trying to send data */
238 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
239 tcp_program_cleanup (wrk, tc);
241 case TCP_STATE_CLOSED:
242 case TCP_STATE_TIME_WAIT:
245 TCP_DBG ("reset state: %u", tc->state);
250 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
252 * It first verifies if segment has a wrapped sequence number (PAWS) and then
253 * does the processing associated to the first four steps (ignoring security
254 * and precedence): sequence number, rst bit and syn bit checks.
256 * @return 0 if segments passes validation.
259 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
260 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
262 /* We could get a burst of RSTs interleaved with acks */
263 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
265 tcp_send_reset (tc0);
266 *error0 = TCP_ERROR_CONNECTION_CLOSED;
270 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
272 *error0 = TCP_ERROR_SEGMENT_INVALID;
276 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
278 *error0 = TCP_ERROR_OPTIONS;
282 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
284 *error0 = TCP_ERROR_PAWS;
285 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
286 vnet_buffer (b0)->tcp.seq_end);
288 /* If it just so happens that a segment updates tsval_recent for a
289 * segment over 24 days old, invalidate tsval_recent. */
290 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
291 tcp_time_now_w_thread (tc0->c_thread_index)))
293 tc0->tsval_recent = tc0->rcv_opts.tsval;
294 clib_warning ("paws failed: 24-day old segment");
296 /* Drop after ack if not rst. Resets can fail paws check as per
297 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
298 * be subjected to the PAWS check by verifying an acceptable value in
300 else if (!tcp_rst (th0))
302 tcp_program_ack (tc0);
303 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
308 /* 1st: check sequence number */
309 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
310 vnet_buffer (b0)->tcp.seq_end))
312 /* SYN/SYN-ACK retransmit */
314 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
316 tcp_options_parse (th0, &tc0->rcv_opts, 1);
317 if (tc0->state == TCP_STATE_SYN_RCVD)
319 tcp_send_synack (tc0);
320 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
321 *error0 = TCP_ERROR_SYNS_RCVD;
325 tcp_program_ack (tc0);
326 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
327 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
332 /* If our window is 0 and the packet is in sequence, let it pass
333 * through for ack processing. It should be dropped later. */
334 if (tc0->rcv_wnd < tc0->snd_mss
335 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
338 /* If we entered recovery and peer did so as well, there's a chance that
339 * dup acks won't be acceptable on either end because seq_end may be less
340 * than rcv_las. This can happen if acks are lost in both directions. */
341 if (tcp_in_recovery (tc0)
342 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
343 tc0->rcv_las - tc0->rcv_wnd)
344 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
345 tc0->rcv_nxt + tc0->rcv_wnd))
348 *error0 = TCP_ERROR_RCV_WND;
350 /* If we advertised a zero rcv_wnd and the segment is in the past or the
351 * next one that we expect, it is probably a window probe */
352 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
353 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
354 tc0->rcv_las + tc0->rcv_opts.mss))
355 *error0 = TCP_ERROR_ZERO_RWND;
357 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
360 /* If not RST, send dup ack */
363 tcp_program_dupack (tc0);
364 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
372 /* 2nd: check the RST bit */
373 if (PREDICT_FALSE (tcp_rst (th0)))
375 tcp_rcv_rst (wrk, tc0);
376 *error0 = TCP_ERROR_RST_RCVD;
380 /* 3rd: check security and precedence (skip) */
382 /* 4th: check the SYN bit (in window) */
383 if (PREDICT_FALSE (tcp_syn (th0)))
385 /* As per RFC5961 send challenge ack instead of reset */
386 tcp_program_ack (tc0);
387 *error0 = TCP_ERROR_SPURIOUS_SYN;
391 /* If segment in window, save timestamp */
392 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
393 vnet_buffer (b0)->tcp.seq_end);
401 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
403 /* SND.UNA =< SEG.ACK =< SND.NXT */
404 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
405 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
407 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
408 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
410 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
413 *error = TCP_ERROR_ACK_INVALID;
418 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
419 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
420 *error = TCP_ERROR_ACK_OK;
425 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
427 * Note that although the original article, srtt and rttvar are scaled
428 * to minimize round-off errors, here we don't. Instead, we rely on
429 * better precision time measurements.
432 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
438 err = mrtt - tc->srtt;
440 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
441 * The increase should be bound */
442 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
443 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
444 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
448 /* First measurement. */
450 tc->rttvar = mrtt >> 1;
455 tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
457 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
461 * Update rtt estimate
463 * We have potentially three sources of rtt measurements:
465 * TSOPT difference between current and echoed timestamp. It has ms
466 * precision and can be computed per ack
467 * ACK timing one sequence number is tracked per rtt with us (micro second)
469 * rate sample if enabled, all outstanding bytes are tracked with us
470 * precision. Every ack and sack are a rtt sample
472 * Middle boxes are known to fiddle with TCP options so we give higher
473 * priority to ACK timing.
475 * For now, rate sample rtts are only used under congestion.
478 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
482 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
483 * RTT because they're ambiguous. */
484 if (tcp_in_cong_recovery (tc))
486 /* Accept rtt estimates for samples that have not been retransmitted */
487 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
488 || (rs->flags & TCP_BTS_IS_RXT))
491 tcp_estimate_rtt_us (tc, rs->rtt_time);
492 mrtt = rs->rtt_time * THZ;
496 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
498 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
499 tcp_estimate_rtt_us (tc, sample);
500 mrtt = clib_max ((u32) (sample * THZ), 1);
501 /* Allow measuring of a new RTT */
504 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
505 * snd_una, i.e., the left side of the send window:
506 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
507 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
509 u32 now = tcp_tstamp (tc);
510 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
515 /* Ignore dubious measurements */
516 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
519 tcp_estimate_rtt (tc, mrtt);
523 /* If we got here something must've been ACKed so make sure boff is 0,
524 * even if mrtt is not valid since we update the rto lower */
532 tcp_estimate_initial_rtt (tcp_connection_t * tc)
534 u8 thread_index = vlib_num_workers ()? 1 : 0;
539 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
540 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
541 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
546 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
547 mrtt = clib_max (mrtt, 1);
548 /* Due to retransmits we don't know the initial mrtt */
549 if (tc->rto_boff && mrtt > 1 * THZ)
551 tc->mrtt_us = (f64) mrtt *TCP_TICK;
554 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
555 tcp_estimate_rtt (tc, mrtt);
560 * Dequeue bytes for connections that have received acks in last burst
563 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
565 u32 thread_index = wrk->vm->thread_index;
566 u32 *pending_deq_acked;
567 tcp_connection_t *tc;
570 if (!vec_len (wrk->pending_deq_acked))
573 pending_deq_acked = wrk->pending_deq_acked;
574 for (i = 0; i < vec_len (pending_deq_acked); i++)
576 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
577 tc->flags &= ~TCP_CONN_DEQ_PENDING;
579 if (PREDICT_FALSE (!tc->burst_acked))
582 /* Dequeue the newly ACKed bytes */
583 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
584 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
586 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
588 if (seq_leq (tc->psh_seq, tc->snd_una))
589 tc->flags &= ~TCP_CONN_PSH_PENDING;
592 if (tcp_is_descheduled (tc))
595 /* If everything has been acked, stop retransmit timer
596 * otherwise update. */
597 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
599 /* Update pacer based on our new cwnd estimate */
600 tcp_connection_tx_pacer_update (tc);
604 _vec_len (wrk->pending_deq_acked) = 0;
608 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
610 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
612 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
613 tc->flags |= TCP_CONN_DEQ_PENDING;
615 tc->burst_acked += tc->bytes_acked;
619 * Try to update snd_wnd based on feedback received from peer.
621 * If successful, and new window is 'effectively' 0, activate persist
625 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
627 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
628 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
629 if (seq_lt (tc->snd_wl1, seq)
630 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
632 tc->snd_wnd = snd_wnd;
635 TCP_EVT (TCP_EVT_SND_WND, tc);
637 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
639 /* Set persist timer if not set and we just got 0 wnd */
640 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
641 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
643 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
644 tcp_persist_timer_set (&wrk->timer_wheel, tc);
649 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
651 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
652 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
655 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
658 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
668 * Init loss recovery/fast recovery.
670 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
671 * updated in @ref tcp_cc_handle_event after fast retransmit
674 tcp_cc_init_congestion (tcp_connection_t * tc)
676 tcp_fastrecovery_on (tc);
677 tc->snd_congestion = tc->snd_nxt;
678 tc->cwnd_acc_bytes = 0;
679 tc->snd_rxt_bytes = 0;
680 tc->rxt_delivered = 0;
681 tc->prr_delivered = 0;
682 tc->prr_start = tc->snd_una;
683 tc->prev_ssthresh = tc->ssthresh;
684 tc->prev_cwnd = tc->cwnd;
686 tc->snd_rxt_ts = tcp_tstamp (tc);
687 tcp_cc_congestion (tc);
689 /* Post retransmit update cwnd to ssthresh and account for the
690 * three segments that have left the network and should've been
691 * buffered at the receiver XXX */
692 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
693 tc->cwnd += 3 * tc->snd_mss;
695 tc->fr_occurences += 1;
696 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
700 tcp_cc_congestion_undo (tcp_connection_t * tc)
702 tc->cwnd = tc->prev_cwnd;
703 tc->ssthresh = tc->prev_ssthresh;
704 tcp_cc_undo_recovery (tc);
705 ASSERT (tc->rto_boff == 0);
706 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
710 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
712 return (tcp_in_recovery (tc) && tc->rto_boff == 1
714 && tcp_opts_tstamp (&tc->rcv_opts)
715 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
719 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
721 return (tcp_cc_is_spurious_timeout_rxt (tc));
725 tcp_should_fastrecover_sack (tcp_connection_t * tc)
727 return (tc->sack_sb.lost_bytes
728 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
729 < tc->sack_sb.sacked_bytes));
733 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
737 /* If of of the two conditions lower hold, reset dupacks because
738 * we're probably after timeout (RFC6582 heuristics).
739 * If Cumulative ack does not cover more than congestion threshold,
741 * 1) The following doesn't hold: The congestion window is greater
742 * than SMSS bytes and the difference between highest_ack
743 * and prev_highest_ack is at most 4*SMSS bytes
744 * 2) Echoed timestamp in the last non-dup ack does not equal the
747 if (seq_leq (tc->snd_una, tc->snd_congestion)
748 && ((!(tc->cwnd > tc->snd_mss
749 && tc->bytes_acked <= 4 * tc->snd_mss))
750 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
756 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
757 || tcp_should_fastrecover_sack (tc));
761 tcp_cc_recover (tcp_connection_t * tc)
763 sack_scoreboard_hole_t *hole;
766 ASSERT (tcp_in_cong_recovery (tc));
768 if (tcp_cc_is_spurious_retransmit (tc))
770 tcp_cc_congestion_undo (tc);
774 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
777 /* Previous recovery left us congested. Continue sending as part
778 * of the current recovery event with an updated snd_congestion */
779 if (tc->sack_sb.sacked_bytes)
781 tc->snd_congestion = tc->snd_nxt;
782 tcp_program_retransmit (tc);
786 tc->rxt_delivered = 0;
787 tc->snd_rxt_bytes = 0;
789 tc->prr_delivered = 0;
791 tc->flags &= ~TCP_CONN_RXT_PENDING;
793 hole = scoreboard_first_hole (&tc->sack_sb);
794 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
795 scoreboard_clear (&tc->sack_sb);
797 if (!tcp_in_recovery (tc) && !is_spurious)
798 tcp_cc_recovered (tc);
800 tcp_fastrecovery_off (tc);
801 tcp_fastrecovery_first_off (tc);
802 tcp_recovery_off (tc);
803 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
805 ASSERT (tc->rto_boff == 0);
806 ASSERT (!tcp_in_cong_recovery (tc));
807 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
813 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
815 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
817 /* Congestion avoidance */
818 tcp_cc_rcv_ack (tc, rs);
820 /* If a cumulative ack, make sure dupacks is 0 */
823 /* When dupacks hits the threshold we only enter fast retransmit if
824 * cumulative ack covers more than snd_congestion. Should snd_una
825 * wrap this test may fail under otherwise valid circumstances.
826 * Therefore, proactively update snd_congestion when wrap detected. */
828 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
829 && seq_gt (tc->snd_congestion, tc->snd_una)))
830 tc->snd_congestion = tc->snd_una - 1;
834 * One function to rule them all ... and in the darkness bind them
837 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
840 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
842 /* If reneging, wait for timer based retransmits */
843 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
847 * If not in recovery, figure out if we should enter
849 if (!tcp_in_cong_recovery (tc))
854 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
855 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
857 if (tcp_should_fastrecover (tc, has_sack))
859 tcp_cc_init_congestion (tc);
862 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
864 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
865 tcp_program_retransmit (tc);
872 * Already in recovery
876 * Process (re)transmit feedback. Output path uses this to decide how much
877 * more data to release into the network
881 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
882 tcp_fastrecovery_first_on (tc);
884 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
885 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
886 - tc->sack_sb.last_bytes_delivered;
892 tc->rcv_dupacks += 1;
893 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
895 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
898 tc->prr_delivered += clib_min (tc->snd_mss,
899 tc->snd_nxt - tc->snd_una);
901 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
905 /* If partial ack, assume that the first un-acked segment was lost */
906 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
907 tcp_fastrecovery_first_on (tc);
911 * See if we can exit and stop retransmitting
913 if (seq_geq (tc->snd_una, tc->snd_congestion))
915 /* If spurious return, we've already updated everything */
916 if (tcp_cc_recover (tc))
918 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
922 /* Treat as congestion avoidance ack */
923 tcp_cc_rcv_ack (tc, rs);
927 tcp_program_retransmit (tc);
930 * Notify cc of the event
933 if (!tc->bytes_acked)
935 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
939 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
940 * reset dupacks to 0. Also needed if in congestion recovery */
943 if (tcp_in_recovery (tc))
944 tcp_cc_rcv_ack (tc, rs);
946 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
950 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
952 if (!tcp_in_cong_recovery (tc))
955 if (tcp_opts_sack_permitted (&tc->rcv_opts))
956 tcp_rcv_sacks (tc, tc->snd_una);
960 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
961 tcp_bt_sample_delivery_rate (tc, rs);
963 tcp_cc_handle_event (tc, rs, 1);
967 * Check if duplicate ack as per RFC5681 Sec. 2
970 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
973 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
974 && seq_gt (tc->snd_nxt, tc->snd_una)
975 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
976 && (prev_snd_wnd == tc->snd_wnd));
980 * Checks if ack is a congestion control event.
983 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
984 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
986 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
987 * defined to be 'duplicate' as well */
988 *is_dack = tc->sack_sb.last_sacked_bytes
989 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
991 return (*is_dack || tcp_in_cong_recovery (tc));
995 * Process incoming ACK
998 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
999 tcp_header_t * th, u32 * error)
1001 u32 prev_snd_wnd, prev_snd_una;
1002 tcp_rate_sample_t rs = { 0 };
1005 TCP_EVT (TCP_EVT_CC_STAT, tc);
1007 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1008 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1010 /* We've probably entered recovery and the peer still has some
1011 * of the data we've sent. Update snd_nxt and accept the ack */
1012 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1013 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1015 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1019 tc->errors.above_ack_wnd += 1;
1020 *error = TCP_ERROR_ACK_FUTURE;
1021 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1025 /* If old ACK, probably it's an old dupack */
1026 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1028 tc->errors.below_ack_wnd += 1;
1029 *error = TCP_ERROR_ACK_OLD;
1030 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1032 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1035 tcp_handle_old_ack (tc, &rs);
1037 /* Don't drop yet */
1044 * Looks okay, process feedback
1047 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1048 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1050 prev_snd_wnd = tc->snd_wnd;
1051 prev_snd_una = tc->snd_una;
1052 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1053 vnet_buffer (b)->tcp.ack_number,
1054 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1055 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1056 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1057 tcp_validate_txf_size (tc, tc->bytes_acked);
1059 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1060 tcp_bt_sample_delivery_rate (tc, &rs);
1062 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1064 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1065 if (tc->bytes_acked)
1066 tcp_program_dequeue (wrk, tc);
1069 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1072 * Check if we have congestion event
1075 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1077 tcp_cc_handle_event (tc, &rs, is_dack);
1078 tc->dupacks_in += is_dack;
1079 if (!tcp_in_cong_recovery (tc))
1081 *error = TCP_ERROR_ACK_OK;
1084 *error = TCP_ERROR_ACK_DUP;
1085 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1091 * Update congestion control (slow start/congestion avoidance)
1093 tcp_cc_update (tc, &rs);
1094 *error = TCP_ERROR_ACK_OK;
1099 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1101 if (!tcp_disconnect_pending (tc))
1103 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1104 tcp_disconnect_pending_on (tc);
1109 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1111 u32 thread_index, *pending_disconnects, *pending_resets;
1112 tcp_connection_t *tc;
1115 if (vec_len (wrk->pending_disconnects))
1117 thread_index = wrk->vm->thread_index;
1118 pending_disconnects = wrk->pending_disconnects;
1119 for (i = 0; i < vec_len (pending_disconnects); i++)
1121 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1122 tcp_disconnect_pending_off (tc);
1123 session_transport_closing_notify (&tc->connection);
1125 _vec_len (wrk->pending_disconnects) = 0;
1128 if (vec_len (wrk->pending_resets))
1130 thread_index = wrk->vm->thread_index;
1131 pending_resets = wrk->pending_resets;
1132 for (i = 0; i < vec_len (pending_resets); i++)
1134 tc = tcp_connection_get (pending_resets[i], thread_index);
1135 tcp_disconnect_pending_off (tc);
1136 tcp_handle_rst (tc);
1138 _vec_len (wrk->pending_resets) = 0;
1143 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1146 /* Reject out-of-order fins */
1147 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1150 /* Account for the FIN and send ack */
1152 tc->flags |= TCP_CONN_FINRCVD;
1153 tcp_program_ack (tc);
1154 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1155 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1156 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1157 tcp_program_disconnect (wrk, tc);
1158 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1159 tcp_cfg.closewait_time);
1160 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1161 *error = TCP_ERROR_FIN_RCVD;
1164 /** Enqueue data for delivery to application */
1166 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1169 int written, error = TCP_ERROR_ENQUEUED;
1171 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1173 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1174 1 /* queue event */ , 1);
1175 tc->bytes_in += written;
1177 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1179 /* Update rcv_nxt */
1180 if (PREDICT_TRUE (written == data_len))
1182 tc->rcv_nxt += written;
1184 /* If more data written than expected, account for out-of-order bytes. */
1185 else if (written > data_len)
1187 tc->rcv_nxt += written;
1188 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1190 else if (written > 0)
1192 /* We've written something but FIFO is probably full now */
1193 tc->rcv_nxt += written;
1194 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1198 /* Packet made it through for ack processing */
1199 if (tc->rcv_wnd < tc->snd_mss)
1200 return TCP_ERROR_ZERO_RWND;
1202 return TCP_ERROR_FIFO_FULL;
1205 /* Update SACK list if need be */
1206 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1208 /* Remove SACK blocks that have been delivered */
1209 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1215 /** Enqueue out-of-order data */
1217 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1223 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1226 /* Enqueue out-of-order data with relative offset */
1227 rv = session_enqueue_stream_connection (&tc->connection, b,
1228 vnet_buffer (b)->tcp.seq_number -
1229 tc->rcv_nxt, 0 /* queue event */ ,
1232 /* Nothing written */
1235 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1236 return TCP_ERROR_FIFO_FULL;
1239 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1240 tc->bytes_in += data_len;
1242 /* Update SACK list if in use */
1243 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1245 ooo_segment_t *newest;
1248 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1250 /* Get the newest segment from the fifo */
1251 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1254 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1255 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1256 start = tc->rcv_nxt + offset;
1257 end = start + ooo_segment_length (s0->rx_fifo, newest);
1258 tcp_update_sack_list (tc, start, end);
1259 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1260 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1264 return TCP_ERROR_ENQUEUED_OOO;
1268 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1270 u32 discard, first = b->current_length;
1271 vlib_main_t *vm = vlib_get_main ();
1273 /* Handle multi-buffer segments */
1274 if (n_bytes_to_drop > b->current_length)
1276 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1280 discard = clib_min (n_bytes_to_drop, b->current_length);
1281 vlib_buffer_advance (b, discard);
1282 b = vlib_get_buffer (vm, b->next_buffer);
1283 n_bytes_to_drop -= discard;
1285 while (n_bytes_to_drop);
1286 if (n_bytes_to_drop > first)
1287 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1290 vlib_buffer_advance (b, n_bytes_to_drop);
1291 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1296 * Receive buffer for connection and handle acks
1298 * It handles both in order or out-of-order data.
1301 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1304 u32 error, n_bytes_to_drop, n_data_bytes;
1306 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1307 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1308 ASSERT (n_data_bytes);
1309 tc->data_segs_in += 1;
1311 /* Handle out-of-order data */
1312 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1314 /* Old sequence numbers allowed through because they overlapped
1316 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1318 /* Completely in the past (possible retransmit). Ack
1319 * retransmissions since we may not have any data to send */
1320 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1322 tcp_program_dupack (tc);
1323 tc->errors.below_data_wnd++;
1324 error = TCP_ERROR_SEGMENT_OLD;
1328 /* Chop off the bytes in the past and see if what is left
1329 * can be enqueued in order */
1330 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1331 n_data_bytes -= n_bytes_to_drop;
1332 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1333 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1335 error = TCP_ERROR_SEGMENT_OLD;
1341 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1342 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1343 tcp_program_dupack (tc);
1344 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1345 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1346 tc->rcv_las + tc->rcv_wnd);
1352 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1353 * segments can be enqueued after fifo tail offset changes. */
1354 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1355 tcp_program_ack (tc);
1363 tcp_header_t tcp_header;
1364 tcp_connection_t tcp_connection;
1368 format_tcp_rx_trace (u8 * s, va_list * args)
1370 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1371 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1372 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1373 tcp_connection_t *tc = &t->tcp_connection;
1374 u32 indent = format_get_indent (s);
1376 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1377 format_tcp_state, tc->state, format_white_space, indent,
1378 format_tcp_header, &t->tcp_header, 128);
1384 format_tcp_rx_trace_short (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 *);
1390 s = format (s, "%d -> %d (%U)",
1391 clib_net_to_host_u16 (t->tcp_header.dst_port),
1392 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1393 t->tcp_connection.state);
1399 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1400 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1404 clib_memcpy_fast (&t0->tcp_connection, tc0,
1405 sizeof (t0->tcp_connection));
1409 th0 = tcp_buffer_hdr (b0);
1411 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1415 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1416 vlib_frame_t * frame, u8 is_ip4)
1420 n_left = frame->n_vectors;
1421 from = vlib_frame_vector_args (frame);
1425 tcp_connection_t *tc0;
1432 b0 = vlib_get_buffer (vm, bi0);
1434 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1436 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1437 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1439 th0 = tcp_buffer_hdr (b0);
1440 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1449 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1450 u8 is_ip4, u32 evt, u32 val)
1453 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1455 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1458 #define tcp_maybe_inc_counter(node_id, err, count) \
1460 if (next0 != tcp_next_drop (is_ip4)) \
1461 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1462 tcp6_##node_id##_node.index, is_ip4, err, \
1465 #define tcp_inc_counter(node_id, err, count) \
1466 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1467 tcp6_##node_id##_node.index, is_ip4, \
1469 #define tcp_maybe_inc_err_counter(cnts, err) \
1471 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1473 #define tcp_inc_err_counter(cnts, err, val) \
1477 #define tcp_store_err_counters(node_id, cnts) \
1480 for (i = 0; i < TCP_N_ERROR; i++) \
1482 tcp_inc_counter(node_id, i, cnts[i]); \
1487 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1488 vlib_frame_t * frame, int is_ip4)
1490 u32 thread_index = vm->thread_index, errors = 0;
1491 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1492 u32 n_left_from, *from, *first_buffer;
1493 u16 err_counters[TCP_N_ERROR] = { 0 };
1495 if (node->flags & VLIB_NODE_FLAG_TRACE)
1496 tcp_established_trace_frame (vm, node, frame, is_ip4);
1498 first_buffer = from = vlib_frame_vector_args (frame);
1499 n_left_from = frame->n_vectors;
1501 while (n_left_from > 0)
1503 u32 bi0, error0 = TCP_ERROR_ACK_OK;
1506 tcp_connection_t *tc0;
1508 if (n_left_from > 1)
1511 pb = vlib_get_buffer (vm, from[1]);
1512 vlib_prefetch_buffer_header (pb, LOAD);
1513 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1520 b0 = vlib_get_buffer (vm, bi0);
1521 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1524 if (PREDICT_FALSE (tc0 == 0))
1526 error0 = TCP_ERROR_INVALID_CONNECTION;
1530 th0 = tcp_buffer_hdr (b0);
1532 /* TODO header prediction fast path */
1534 /* 1-4: check SEQ, RST, SYN */
1535 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
1537 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
1541 /* 5: check the ACK field */
1542 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
1545 /* 6: check the URG bit TODO */
1547 /* 7: process the segment text */
1548 if (vnet_buffer (b0)->tcp.data_len)
1549 error0 = tcp_segment_rcv (wrk, tc0, b0);
1551 /* 8: check the FIN bit */
1552 if (PREDICT_FALSE (tcp_is_fin (th0)))
1553 tcp_rcv_fin (wrk, tc0, b0, &error0);
1556 tcp_inc_err_counter (err_counters, error0, 1);
1559 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1561 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1562 tcp_store_err_counters (established, err_counters);
1563 tcp_handle_postponed_dequeues (wrk);
1564 tcp_handle_disconnects (wrk);
1565 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
1567 return frame->n_vectors;
1570 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1571 vlib_node_runtime_t * node,
1572 vlib_frame_t * from_frame)
1574 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1577 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1578 vlib_node_runtime_t * node,
1579 vlib_frame_t * from_frame)
1581 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1585 VLIB_REGISTER_NODE (tcp4_established_node) =
1587 .name = "tcp4-established",
1588 /* Takes a vector of packets. */
1589 .vector_size = sizeof (u32),
1590 .n_errors = TCP_N_ERROR,
1591 .error_strings = tcp_error_strings,
1592 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1595 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1596 foreach_tcp_state_next
1599 .format_trace = format_tcp_rx_trace_short,
1604 VLIB_REGISTER_NODE (tcp6_established_node) =
1606 .name = "tcp6-established",
1607 /* Takes a vector of packets. */
1608 .vector_size = sizeof (u32),
1609 .n_errors = TCP_N_ERROR,
1610 .error_strings = tcp_error_strings,
1611 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1614 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1615 foreach_tcp_state_next
1618 .format_trace = format_tcp_rx_trace_short,
1624 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1627 transport_connection_t *tmp = 0;
1634 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1637 u8 is_ip_valid = 0, val_l, val_r;
1639 if (tc->connection.is_ip4)
1641 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1643 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1644 &tc->connection.lcl_ip.ip4);
1645 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1646 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1647 &tc->connection.rmt_ip.ip4);
1648 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1649 is_ip_valid = val_l && val_r;
1653 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1655 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1656 &tc->connection.lcl_ip.ip6);
1657 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1658 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1659 &tc->connection.rmt_ip.ip6);
1660 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1661 is_ip_valid = val_l && val_r;
1664 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1665 && (tc->state == TCP_STATE_LISTEN
1666 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1670 handle = session_lookup_half_open_handle (&tc->connection);
1671 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1672 tc->c_proto, tc->c_is_ip4);
1676 if (tmp->lcl_port == hdr->dst_port
1677 && tmp->rmt_port == hdr->src_port)
1679 TCP_DBG ("half-open is valid!");
1688 * Lookup transport connection
1690 static tcp_connection_t *
1691 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1695 transport_connection_t *tconn;
1696 tcp_connection_t *tc;
1701 ip4 = vlib_buffer_get_current (b);
1702 tcp = ip4_next_header (ip4);
1703 tconn = session_lookup_connection_wt4 (fib_index,
1708 TRANSPORT_PROTO_TCP,
1709 thread_index, &is_filtered);
1710 tc = tcp_get_connection_from_transport (tconn);
1711 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1716 ip6 = vlib_buffer_get_current (b);
1717 tcp = ip6_next_header (ip6);
1718 tconn = session_lookup_connection_wt6 (fib_index,
1723 TRANSPORT_PROTO_TCP,
1724 thread_index, &is_filtered);
1725 tc = tcp_get_connection_from_transport (tconn);
1726 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1731 static tcp_connection_t *
1732 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1738 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1739 tcp_header_t *tcp = tcp_buffer_hdr (b);
1740 s = session_lookup_listener4 (fib_index,
1742 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1746 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1747 tcp_header_t *tcp = tcp_buffer_hdr (b);
1748 s = session_lookup_listener6 (fib_index,
1750 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1753 if (PREDICT_TRUE (s != 0))
1754 return tcp_get_connection_from_transport (transport_get_listener
1755 (TRANSPORT_PROTO_TCP,
1756 s->connection_index));
1762 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1764 vnet_main_t *vnm = vnet_get_main ();
1765 const dpo_id_t *dpo;
1766 const load_balance_t *lb;
1767 vnet_hw_interface_t *hw_if;
1768 u32 sw_if_idx, lb_idx;
1772 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1773 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1777 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1778 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1781 lb = load_balance_get (lb_idx);
1782 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1784 dpo = load_balance_get_bucket_i (lb, 0);
1786 sw_if_idx = dpo_get_urpf (dpo);
1787 if (PREDICT_FALSE (sw_if_idx == ~0))
1790 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1791 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
1792 tc->cfg_flags |= TCP_CFG_F_TSO;
1796 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1797 vlib_frame_t * from_frame, int is_ip4)
1799 u32 n_left_from, *from, *first_buffer, errors = 0;
1800 u32 my_thread_index = vm->thread_index;
1801 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
1803 from = first_buffer = vlib_frame_vector_args (from_frame);
1804 n_left_from = from_frame->n_vectors;
1806 while (n_left_from > 0)
1808 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
1809 tcp_connection_t *tc0, *new_tc0;
1810 tcp_header_t *tcp0 = 0;
1818 b0 = vlib_get_buffer (vm, bi0);
1820 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
1821 if (PREDICT_FALSE (tc0 == 0))
1823 error0 = TCP_ERROR_INVALID_CONNECTION;
1827 /* Half-open completed recently but the connection was't removed
1828 * yet by the owning thread */
1829 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1831 /* Make sure the connection actually exists */
1832 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
1833 my_thread_index, is_ip4));
1834 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
1838 ack0 = vnet_buffer (b0)->tcp.ack_number;
1839 seq0 = vnet_buffer (b0)->tcp.seq_number;
1840 tcp0 = tcp_buffer_hdr (b0);
1842 /* Crude check to see if the connection handle does not match
1843 * the packet. Probably connection just switched to established */
1844 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1845 || tcp0->src_port != tc0->c_rmt_port))
1847 error0 = TCP_ERROR_INVALID_CONNECTION;
1851 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
1852 && !tcp_syn (tcp0)))
1854 error0 = TCP_ERROR_SEGMENT_INVALID;
1858 /* SYNs consume sequence numbers */
1859 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
1862 * 1. check the ACK bit
1866 * If the ACK bit is set
1867 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1868 * the RST bit is set, if so drop the segment and return)
1869 * <SEQ=SEG.ACK><CTL=RST>
1870 * and discard the segment. Return.
1871 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1875 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
1877 if (!tcp_rst (tcp0))
1878 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1879 error0 = TCP_ERROR_RCV_WND;
1883 /* Make sure ACK is valid */
1884 if (seq_gt (tc0->snd_una, ack0))
1886 error0 = TCP_ERROR_ACK_INVALID;
1892 * 2. check the RST bit
1897 /* If ACK is acceptable, signal client that peer is not
1898 * willing to accept connection and drop connection*/
1900 tcp_rcv_rst (wrk, tc0);
1901 error0 = TCP_ERROR_RST_RCVD;
1906 * 3. check the security and precedence (skipped)
1910 * 4. check the SYN bit
1913 /* No SYN flag. Drop. */
1914 if (!tcp_syn (tcp0))
1916 error0 = TCP_ERROR_SEGMENT_INVALID;
1921 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
1923 error0 = TCP_ERROR_OPTIONS;
1927 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1928 * current thread pool. */
1929 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
1930 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
1931 new_tc0->irs = seq0;
1932 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1933 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1935 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
1937 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
1938 new_tc0->tsval_recent_age = tcp_time_now ();
1941 if (tcp_opts_wscale (&new_tc0->rcv_opts))
1942 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
1944 new_tc0->rcv_wscale = 0;
1946 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
1947 << new_tc0->snd_wscale;
1948 new_tc0->snd_wl1 = seq0;
1949 new_tc0->snd_wl2 = ack0;
1951 tcp_connection_init_vars (new_tc0);
1953 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1954 if (PREDICT_TRUE (tcp_ack (tcp0)))
1956 /* Our SYN is ACKed: we have iss < ack = snd_una */
1958 /* TODO Dequeue acknowledged segments if we support Fast Open */
1959 new_tc0->snd_una = ack0;
1960 new_tc0->state = TCP_STATE_ESTABLISHED;
1962 /* Make sure las is initialized for the wnd computation */
1963 new_tc0->rcv_las = new_tc0->rcv_nxt;
1965 /* Notify app that we have connection. If session layer can't
1966 * allocate session send reset */
1967 if (session_stream_connect_notify (&new_tc0->connection,
1970 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
1971 tcp_connection_cleanup (new_tc0);
1972 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1976 new_tc0->tx_fifo_size =
1977 transport_tx_fifo_size (&new_tc0->connection);
1978 /* Update rtt with the syn-ack sample */
1979 tcp_estimate_initial_rtt (new_tc0);
1980 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
1981 error0 = TCP_ERROR_SYN_ACKS_RCVD;
1983 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1986 new_tc0->state = TCP_STATE_SYN_RCVD;
1988 /* Notify app that we have connection */
1989 if (session_stream_connect_notify (&new_tc0->connection,
1992 tcp_connection_cleanup (new_tc0);
1993 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1994 TCP_EVT (TCP_EVT_RST_SENT, tc0);
1995 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1999 new_tc0->tx_fifo_size =
2000 transport_tx_fifo_size (&new_tc0->connection);
2001 new_tc0->rtt_ts = 0;
2002 tcp_init_snd_vars (new_tc0);
2003 tcp_send_synack (new_tc0);
2004 error0 = TCP_ERROR_SYNS_RCVD;
2008 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2009 tcp_check_tx_offload (new_tc0, is_ip4);
2011 /* Read data, if any */
2012 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2014 clib_warning ("rcvd data in syn-sent");
2015 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2016 if (error0 == TCP_ERROR_ACK_OK)
2017 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2021 /* Send ack now instead of programming it because connection was
2022 * just established and it's not optional. */
2023 tcp_send_ack (new_tc0);
2028 /* If this is not the owning thread, wait for syn retransmit to
2029 * expire and cleanup then */
2030 if (tcp_half_open_connection_cleanup (tc0))
2031 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2035 tcp_inc_counter (syn_sent, error0, 1);
2036 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2038 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2039 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2040 clib_memcpy_fast (&t0->tcp_connection, tc0,
2041 sizeof (t0->tcp_connection));
2045 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2047 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2048 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2049 tcp_handle_disconnects (wrk);
2051 return from_frame->n_vectors;
2054 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2055 vlib_node_runtime_t * node,
2056 vlib_frame_t * from_frame)
2058 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2061 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2062 vlib_node_runtime_t * node,
2063 vlib_frame_t * from_frame)
2065 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2069 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2071 .name = "tcp4-syn-sent",
2072 /* Takes a vector of packets. */
2073 .vector_size = sizeof (u32),
2074 .n_errors = TCP_N_ERROR,
2075 .error_strings = tcp_error_strings,
2076 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2079 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2080 foreach_tcp_state_next
2083 .format_trace = format_tcp_rx_trace_short,
2088 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2090 .name = "tcp6-syn-sent",
2091 /* Takes a vector of packets. */
2092 .vector_size = sizeof (u32),
2093 .n_errors = TCP_N_ERROR,
2094 .error_strings = tcp_error_strings,
2095 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2098 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2099 foreach_tcp_state_next
2102 .format_trace = format_tcp_rx_trace_short,
2107 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2108 * as per RFC793 p. 64
2111 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2112 vlib_frame_t * from_frame, int is_ip4)
2114 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2115 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2116 u32 n_left_from, *from, max_dequeue;
2118 from = first_buffer = vlib_frame_vector_args (from_frame);
2119 n_left_from = from_frame->n_vectors;
2121 while (n_left_from > 0)
2123 u32 bi0, error0 = TCP_ERROR_NONE;
2124 tcp_header_t *tcp0 = 0;
2125 tcp_connection_t *tc0;
2133 b0 = vlib_get_buffer (vm, bi0);
2134 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2136 if (PREDICT_FALSE (tc0 == 0))
2138 error0 = TCP_ERROR_INVALID_CONNECTION;
2142 tcp0 = tcp_buffer_hdr (b0);
2143 is_fin0 = tcp_is_fin (tcp0);
2147 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2149 tcp_connection_t *tmp;
2150 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2152 if (tmp->state != tc0->state)
2154 if (tc0->state != TCP_STATE_CLOSED)
2155 clib_warning ("state changed");
2162 * Special treatment for CLOSED
2164 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2166 error0 = TCP_ERROR_CONNECTION_CLOSED;
2171 * For all other states (except LISTEN)
2174 /* 1-4: check SEQ, RST, SYN */
2175 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2178 /* 5: check the ACK field */
2181 case TCP_STATE_SYN_RCVD:
2183 /* Make sure the segment is exactly right */
2184 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2186 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2187 error0 = TCP_ERROR_SEGMENT_INVALID;
2192 * If the segment acknowledgment is not acceptable, form a
2194 * <SEQ=SEG.ACK><CTL=RST>
2197 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2199 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2200 error0 = TCP_ERROR_SEGMENT_INVALID;
2204 /* Update rtt and rto */
2205 tcp_estimate_initial_rtt (tc0);
2206 tcp_connection_tx_pacer_update (tc0);
2208 /* Switch state to ESTABLISHED */
2209 tc0->state = TCP_STATE_ESTABLISHED;
2210 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2212 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2213 tcp_check_tx_offload (tc0, is_ip4);
2215 /* Initialize session variables */
2216 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2217 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2218 << tc0->rcv_opts.wscale;
2219 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2220 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2222 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2223 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc0);
2224 if (session_stream_accept_notify (&tc0->connection))
2226 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2227 tcp_send_reset (tc0);
2228 session_transport_delete_notify (&tc0->connection);
2229 tcp_connection_cleanup (tc0);
2232 error0 = TCP_ERROR_ACK_OK;
2234 case TCP_STATE_ESTABLISHED:
2235 /* We can get packets in established state here because they
2236 * were enqueued before state change */
2237 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2241 case TCP_STATE_FIN_WAIT_1:
2242 /* In addition to the processing for the ESTABLISHED state, if
2243 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2244 * continue processing in that state. */
2245 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2248 /* Still have to send the FIN */
2249 if (tc0->flags & TCP_CONN_FINPNDG)
2251 /* TX fifo finally drained */
2252 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2253 if (max_dequeue <= tc0->burst_acked)
2255 /* If a fin was received and data was acked extend wait */
2256 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2257 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2258 tcp_cfg.closewait_time);
2260 /* If FIN is ACKed */
2261 else if (tc0->snd_una == tc0->snd_nxt)
2263 /* Stop all retransmit timers because we have nothing more
2265 tcp_connection_timers_reset (tc0);
2267 /* We already have a FIN but didn't transition to CLOSING
2268 * because of outstanding tx data. Close the connection. */
2269 if (tc0->flags & TCP_CONN_FINRCVD)
2271 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2272 session_transport_closed_notify (&tc0->connection);
2273 tcp_program_cleanup (wrk, tc0);
2277 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2278 /* Enable waitclose because we're willing to wait for peer's
2279 * FIN but not indefinitely. */
2280 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2281 tcp_cfg.finwait2_time);
2283 /* Don't try to deq the FIN acked */
2284 if (tc0->burst_acked > 1)
2285 session_tx_fifo_dequeue_drop (&tc0->connection,
2286 tc0->burst_acked - 1);
2287 tc0->burst_acked = 0;
2290 case TCP_STATE_FIN_WAIT_2:
2291 /* In addition to the processing for the ESTABLISHED state, if
2292 * the retransmission queue is empty, the user's CLOSE can be
2293 * acknowledged ("ok") but do not delete the TCB. */
2294 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2296 tc0->burst_acked = 0;
2298 case TCP_STATE_CLOSE_WAIT:
2299 /* Do the same processing as for the ESTABLISHED state. */
2300 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2303 if (!(tc0->flags & TCP_CONN_FINPNDG))
2306 /* Still have outstanding tx data */
2307 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2308 if (max_dequeue > tc0->burst_acked)
2312 tcp_connection_timers_reset (tc0);
2313 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2314 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2315 tcp_cfg.lastack_time);
2317 case TCP_STATE_CLOSING:
2318 /* In addition to the processing for the ESTABLISHED state, if
2319 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2320 * otherwise ignore the segment. */
2321 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2324 if (tc0->snd_una != tc0->snd_nxt)
2327 tcp_connection_timers_reset (tc0);
2328 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2329 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2330 tcp_cfg.timewait_time);
2331 session_transport_closed_notify (&tc0->connection);
2335 case TCP_STATE_LAST_ACK:
2336 /* The only thing that [should] arrive in this state is an
2337 * acknowledgment of our FIN. If our FIN is now acknowledged,
2338 * delete the TCB, enter the CLOSED state, and return. */
2340 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2343 /* Apparently our ACK for the peer's FIN was lost */
2344 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2350 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2351 session_transport_closed_notify (&tc0->connection);
2353 /* Don't free the connection from the data path since
2354 * we can't ensure that we have no packets already enqueued
2355 * to output. Rely instead on the waitclose timer */
2356 tcp_connection_timers_reset (tc0);
2357 tcp_program_cleanup (tcp_get_worker (tc0->c_thread_index), tc0);
2362 case TCP_STATE_TIME_WAIT:
2363 /* The only thing that can arrive in this state is a
2364 * retransmission of the remote FIN. Acknowledge it, and restart
2365 * the 2 MSL timeout. */
2367 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2373 tcp_program_ack (tc0);
2374 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2375 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 (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2418 tcp_cfg.closewait_time);
2420 case TCP_STATE_SYN_RCVD:
2421 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2422 * notified yet, set a cleanup timer instead of relying on
2423 * disconnect notify and the implicit close call. */
2424 tcp_connection_timers_reset (tc0);
2427 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2428 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2429 tcp_cfg.lastack_time);
2431 case TCP_STATE_CLOSE_WAIT:
2432 case TCP_STATE_CLOSING:
2433 case TCP_STATE_LAST_ACK:
2436 case TCP_STATE_FIN_WAIT_1:
2439 if (tc0->flags & TCP_CONN_FINPNDG)
2441 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2442 * sending it. Since we already received a fin, do not wait
2444 tc0->flags |= TCP_CONN_FINRCVD;
2445 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2446 tcp_cfg.closewait_time);
2450 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2451 tcp_program_ack (tc0);
2452 /* Wait for ACK for our FIN but not forever */
2453 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2454 tcp_cfg.closing_time);
2457 case TCP_STATE_FIN_WAIT_2:
2458 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2460 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2461 tcp_connection_timers_reset (tc0);
2462 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2463 tcp_cfg.timewait_time);
2464 tcp_program_ack (tc0);
2465 session_transport_closed_notify (&tc0->connection);
2467 case TCP_STATE_TIME_WAIT:
2468 /* Remain in the TIME-WAIT state. Restart the time-wait
2471 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2472 tcp_cfg.timewait_time);
2475 error0 = TCP_ERROR_FIN_RCVD;
2479 tcp_inc_counter (rcv_process, error0, 1);
2480 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2482 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2483 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2487 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2489 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2490 tcp_handle_postponed_dequeues (wrk);
2491 tcp_handle_disconnects (wrk);
2492 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2494 return from_frame->n_vectors;
2497 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2498 vlib_node_runtime_t * node,
2499 vlib_frame_t * from_frame)
2501 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2504 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2505 vlib_node_runtime_t * node,
2506 vlib_frame_t * from_frame)
2508 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2512 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2514 .name = "tcp4-rcv-process",
2515 /* Takes a vector of packets. */
2516 .vector_size = sizeof (u32),
2517 .n_errors = TCP_N_ERROR,
2518 .error_strings = tcp_error_strings,
2519 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2522 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2523 foreach_tcp_state_next
2526 .format_trace = format_tcp_rx_trace_short,
2531 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2533 .name = "tcp6-rcv-process",
2534 /* Takes a vector of packets. */
2535 .vector_size = sizeof (u32),
2536 .n_errors = TCP_N_ERROR,
2537 .error_strings = tcp_error_strings,
2538 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2541 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2542 foreach_tcp_state_next
2545 .format_trace = format_tcp_rx_trace_short,
2550 * LISTEN state processing as per RFC 793 p. 65
2553 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2554 vlib_frame_t * from_frame, int is_ip4)
2556 u32 n_left_from, *from, n_syns = 0, *first_buffer;
2557 u32 thread_index = vm->thread_index;
2559 from = first_buffer = vlib_frame_vector_args (from_frame);
2560 n_left_from = from_frame->n_vectors;
2562 while (n_left_from > 0)
2564 u32 bi, error = TCP_ERROR_NONE;
2565 tcp_connection_t *lc, *child;
2572 b = vlib_get_buffer (vm, bi);
2574 lc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2575 if (PREDICT_FALSE (lc == 0))
2577 tcp_connection_t *tc;
2578 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2580 if (tc->state != TCP_STATE_TIME_WAIT)
2582 error = TCP_ERROR_CREATE_EXISTS;
2585 lc = tcp_lookup_listener (b, tc->c_fib_index, is_ip4);
2586 /* clean up the old session */
2587 tcp_connection_del (tc);
2590 /* Make sure connection wasn't just created */
2591 child = tcp_lookup_connection (lc->c_fib_index, b, thread_index,
2593 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2595 error = TCP_ERROR_CREATE_EXISTS;
2599 /* Create child session. For syn-flood protection use filter */
2601 /* 1. first check for an RST: handled in dispatch */
2602 /* if (tcp_rst (th0))
2606 /* 2. second check for an ACK: handled in dispatch */
2607 /* if (tcp_ack (th0))
2609 tcp_send_reset (b0, is_ip4);
2614 /* 3. check for a SYN (did that already) */
2616 /* Create child session and send SYN-ACK */
2617 child = tcp_connection_alloc (thread_index);
2619 if (tcp_options_parse (tcp_buffer_hdr (b), &child->rcv_opts, 1))
2621 error = TCP_ERROR_OPTIONS;
2622 tcp_connection_free (child);
2626 tcp_init_w_buffer (child, b, is_ip4);
2628 child->state = TCP_STATE_SYN_RCVD;
2629 child->c_fib_index = lc->c_fib_index;
2630 child->cc_algo = lc->cc_algo;
2631 tcp_connection_init_vars (child);
2632 child->rto = TCP_RTO_MIN;
2635 * This initializes elog track, must be done before synack.
2636 * We also do it before possible tcp_connection_cleanup() as it
2637 * generates TCP_EVT_DELETE event.
2639 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2641 if (session_stream_accept (&child->connection, lc->c_s_index,
2642 lc->c_thread_index, 0 /* notify */ ))
2644 tcp_connection_cleanup (child);
2645 error = TCP_ERROR_CREATE_SESSION_FAIL;
2649 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2651 tcp_send_synack (child);
2655 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
2658 t = vlib_add_trace (vm, node, b, sizeof (*t));
2659 clib_memcpy_fast (&t->tcp_header, tcp_buffer_hdr (b),
2660 sizeof (t->tcp_header));
2661 clib_memcpy_fast (&t->tcp_connection, lc,
2662 sizeof (t->tcp_connection));
2665 n_syns += (error == TCP_ERROR_NONE);
2668 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2669 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2671 return from_frame->n_vectors;
2674 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2675 vlib_frame_t * from_frame)
2677 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2680 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2681 vlib_frame_t * from_frame)
2683 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2687 VLIB_REGISTER_NODE (tcp4_listen_node) =
2689 .name = "tcp4-listen",
2690 /* Takes a vector of packets. */
2691 .vector_size = sizeof (u32),
2692 .n_errors = TCP_N_ERROR,
2693 .error_strings = tcp_error_strings,
2694 .n_next_nodes = TCP_LISTEN_N_NEXT,
2697 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2698 foreach_tcp_state_next
2701 .format_trace = format_tcp_rx_trace_short,
2706 VLIB_REGISTER_NODE (tcp6_listen_node) =
2708 .name = "tcp6-listen",
2709 /* Takes a vector of packets. */
2710 .vector_size = sizeof (u32),
2711 .n_errors = TCP_N_ERROR,
2712 .error_strings = tcp_error_strings,
2713 .n_next_nodes = TCP_LISTEN_N_NEXT,
2716 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2717 foreach_tcp_state_next
2720 .format_trace = format_tcp_rx_trace_short,
2724 typedef enum _tcp_input_next
2726 TCP_INPUT_NEXT_DROP,
2727 TCP_INPUT_NEXT_LISTEN,
2728 TCP_INPUT_NEXT_RCV_PROCESS,
2729 TCP_INPUT_NEXT_SYN_SENT,
2730 TCP_INPUT_NEXT_ESTABLISHED,
2731 TCP_INPUT_NEXT_RESET,
2732 TCP_INPUT_NEXT_PUNT,
2736 #define foreach_tcp4_input_next \
2737 _ (DROP, "ip4-drop") \
2738 _ (LISTEN, "tcp4-listen") \
2739 _ (RCV_PROCESS, "tcp4-rcv-process") \
2740 _ (SYN_SENT, "tcp4-syn-sent") \
2741 _ (ESTABLISHED, "tcp4-established") \
2742 _ (RESET, "tcp4-reset") \
2743 _ (PUNT, "ip4-punt")
2745 #define foreach_tcp6_input_next \
2746 _ (DROP, "ip6-drop") \
2747 _ (LISTEN, "tcp6-listen") \
2748 _ (RCV_PROCESS, "tcp6-rcv-process") \
2749 _ (SYN_SENT, "tcp6-syn-sent") \
2750 _ (ESTABLISHED, "tcp6-established") \
2751 _ (RESET, "tcp6-reset") \
2752 _ (PUNT, "ip6-punt")
2754 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2757 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2758 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2760 tcp_connection_t *tc;
2765 for (i = 0; i < n_bufs; i++)
2767 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2769 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2770 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2772 tcp = vlib_buffer_get_current (bs[i]);
2773 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2779 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2781 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2783 *next = TCP_INPUT_NEXT_DROP;
2785 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2787 *next = TCP_INPUT_NEXT_PUNT;
2788 *error = TCP_ERROR_PUNT;
2792 *next = TCP_INPUT_NEXT_RESET;
2793 *error = TCP_ERROR_NO_LISTENER;
2798 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2799 vlib_buffer_t * b, u16 * next,
2800 vlib_node_runtime_t * error_node)
2806 tcp = tcp_buffer_hdr (b);
2807 flags = tcp->flags & filter_flags;
2808 *next = tm->dispatch_table[tc->state][flags].next;
2809 error = tm->dispatch_table[tc->state][flags].error;
2812 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2814 b->error = error_node->errors[error];
2815 if (error == TCP_ERROR_DISPATCH)
2816 clib_warning ("tcp conn %u disp error state %U flags %U",
2817 tc->c_c_index, format_tcp_state, tc->state,
2818 format_tcp_flags, (int) flags);
2823 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2824 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2826 u32 n_left_from, *from, thread_index = vm->thread_index;
2827 tcp_main_t *tm = vnet_get_tcp_main ();
2828 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2829 u16 nexts[VLIB_FRAME_SIZE], *next;
2831 tcp_set_time_now (tcp_get_worker (thread_index));
2833 from = vlib_frame_vector_args (frame);
2834 n_left_from = frame->n_vectors;
2835 vlib_get_buffers (vm, from, bufs, n_left_from);
2840 while (n_left_from >= 4)
2842 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2843 tcp_connection_t *tc0, *tc1;
2846 vlib_prefetch_buffer_header (b[2], STORE);
2847 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2849 vlib_prefetch_buffer_header (b[3], STORE);
2850 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2853 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2855 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2857 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2860 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2862 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2863 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2865 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2866 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2868 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2869 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2873 if (PREDICT_TRUE (tc0 != 0))
2875 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2876 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2877 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2881 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2882 b[0]->error = node->errors[error0];
2885 if (PREDICT_TRUE (tc1 != 0))
2887 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2888 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2889 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2893 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2894 b[1]->error = node->errors[error1];
2902 while (n_left_from > 0)
2904 tcp_connection_t *tc0;
2905 u32 error0 = TCP_ERROR_NO_LISTENER;
2907 if (n_left_from > 1)
2909 vlib_prefetch_buffer_header (b[1], STORE);
2910 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2913 next[0] = TCP_INPUT_NEXT_DROP;
2914 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2916 if (PREDICT_TRUE (tc0 != 0))
2918 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2919 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2920 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2924 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2925 b[0]->error = node->errors[error0];
2933 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2934 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2936 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2937 return frame->n_vectors;
2940 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2941 vlib_node_runtime_t * node,
2942 vlib_frame_t * from_frame)
2944 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2945 1 /* is_nolookup */ );
2948 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2949 vlib_node_runtime_t * node,
2950 vlib_frame_t * from_frame)
2952 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2953 1 /* is_nolookup */ );
2957 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2959 .name = "tcp4-input-nolookup",
2960 /* Takes a vector of packets. */
2961 .vector_size = sizeof (u32),
2962 .n_errors = TCP_N_ERROR,
2963 .error_strings = tcp_error_strings,
2964 .n_next_nodes = TCP_INPUT_N_NEXT,
2967 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2968 foreach_tcp4_input_next
2971 .format_buffer = format_tcp_header,
2972 .format_trace = format_tcp_rx_trace,
2977 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2979 .name = "tcp6-input-nolookup",
2980 /* Takes a vector of packets. */
2981 .vector_size = sizeof (u32),
2982 .n_errors = TCP_N_ERROR,
2983 .error_strings = tcp_error_strings,
2984 .n_next_nodes = TCP_INPUT_N_NEXT,
2987 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2988 foreach_tcp6_input_next
2991 .format_buffer = format_tcp_header,
2992 .format_trace = format_tcp_rx_trace,
2996 VLIB_NODE_FN (tcp4_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, 1 /* is_ip4 */ ,
3000 0 /* is_nolookup */ );
3003 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3004 vlib_frame_t * from_frame)
3006 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3007 0 /* is_nolookup */ );
3011 VLIB_REGISTER_NODE (tcp4_input_node) =
3013 .name = "tcp4-input",
3014 /* Takes a vector of packets. */
3015 .vector_size = sizeof (u32),
3016 .n_errors = TCP_N_ERROR,
3017 .error_strings = tcp_error_strings,
3018 .n_next_nodes = TCP_INPUT_N_NEXT,
3021 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3022 foreach_tcp4_input_next
3025 .format_buffer = format_tcp_header,
3026 .format_trace = format_tcp_rx_trace,
3031 VLIB_REGISTER_NODE (tcp6_input_node) =
3033 .name = "tcp6-input",
3034 /* Takes a vector of packets. */
3035 .vector_size = sizeof (u32),
3036 .n_errors = TCP_N_ERROR,
3037 .error_strings = tcp_error_strings,
3038 .n_next_nodes = TCP_INPUT_N_NEXT,
3041 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3042 foreach_tcp6_input_next
3045 .format_buffer = format_tcp_header,
3046 .format_trace = format_tcp_rx_trace,
3050 #ifndef CLIB_MARCH_VARIANT
3052 tcp_dispatch_table_init (tcp_main_t * tm)
3055 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3056 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3058 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3059 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3062 #define _(t,f,n,e) \
3064 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3065 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3068 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3069 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3070 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3071 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3072 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3073 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3074 TCP_ERROR_ACK_INVALID);
3075 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3076 TCP_ERROR_SEGMENT_INVALID);
3077 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3078 TCP_ERROR_SEGMENT_INVALID);
3079 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3080 TCP_ERROR_INVALID_CONNECTION);
3081 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3082 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3083 TCP_ERROR_SEGMENT_INVALID);
3084 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3085 TCP_ERROR_SEGMENT_INVALID);
3086 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3087 TCP_ERROR_SEGMENT_INVALID);
3088 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3089 TCP_ERROR_SEGMENT_INVALID);
3090 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3091 TCP_ERROR_SEGMENT_INVALID);
3092 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3093 TCP_ERROR_SEGMENT_INVALID);
3094 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3095 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3096 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3097 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3098 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3099 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3101 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3102 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3104 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3106 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3107 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3108 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3109 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3111 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3113 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3114 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3115 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3117 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3118 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3119 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3120 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3121 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3122 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3123 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3124 /* SYN-ACK for a SYN */
3125 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3127 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3128 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3129 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3131 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3132 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3134 /* ACK for for established connection -> tcp-established. */
3135 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3136 /* FIN for for established connection -> tcp-established. */
3137 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3138 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3140 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3142 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3143 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3144 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3146 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3147 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3148 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3149 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3150 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3151 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3152 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3153 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3155 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3156 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3158 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3160 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3161 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3162 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3163 /* ACK or FIN-ACK to our FIN */
3164 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3165 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3167 /* FIN in reply to our FIN from the other side */
3168 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3169 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3170 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3172 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3173 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3174 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3175 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3176 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3177 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3178 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3180 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3181 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3182 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3183 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3185 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3187 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3188 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3189 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3190 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3192 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3193 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3194 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3195 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3197 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3199 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3200 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3201 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3202 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3204 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3205 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3207 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3209 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3210 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3211 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3213 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3214 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3215 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3216 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3217 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3218 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 /* FIN confirming that the peer (app) has closed */
3220 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3221 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3227 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3230 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3231 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3233 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3235 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3236 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3237 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3239 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3241 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3242 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3243 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3245 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3246 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3247 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3248 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3249 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3250 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3251 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3252 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3254 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3255 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3257 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3259 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3260 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3261 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3262 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3263 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3265 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3266 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3268 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3269 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3270 * incoming segment not containing a RST causes a RST to be sent in
3272 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3273 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3274 TCP_ERROR_CONNECTION_CLOSED);
3275 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3276 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3277 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3278 TCP_ERROR_CONNECTION_CLOSED);
3282 static clib_error_t *
3283 tcp_input_init (vlib_main_t * vm)
3285 clib_error_t *error = 0;
3286 tcp_main_t *tm = vnet_get_tcp_main ();
3288 if ((error = vlib_call_init_function (vm, tcp_init)))
3291 /* Initialize dispatch table. */
3292 tcp_dispatch_table_init (tm);
3297 VLIB_INIT_FUNCTION (tcp_input_init);
3299 #endif /* CLIB_MARCH_VARIANT */
3302 * fd.io coding-style-patch-verification: ON
3305 * eval: (c-set-style "gnu")