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, SESSION_E_REFUSED);
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_nxt)
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 in 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.
431 * A known limitation of the algorithm is that a drop in rtt results in a
432 * rttvar increase and bigger RTO.
434 * mrtt must be provided in @ref TCP_TICK multiples, i.e., in us. Note that
435 * timestamps are measured as ms ticks so they must be converted before
436 * calling this function.
439 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
443 err = mrtt - tc->srtt;
444 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
445 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
446 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
450 tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
452 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
456 * Update rtt estimate
458 * We have potentially three sources of rtt measurements:
460 * TSOPT difference between current and echoed timestamp. It has ms
461 * precision and can be computed per ack
462 * ACK timing one sequence number is tracked per rtt with us (micro second)
464 * rate sample if enabled, all outstanding bytes are tracked with us
465 * precision. Every ack and sack are a rtt sample
467 * Middle boxes are known to fiddle with TCP options so we give higher
468 * priority to ACK timing.
470 * For now, rate sample rtts are only used under congestion.
473 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
477 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
478 * RTT because they're ambiguous. */
479 if (tcp_in_cong_recovery (tc))
481 /* Accept rtt estimates for samples that have not been retransmitted */
482 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
483 || (rs->flags & TCP_BTS_IS_RXT))
486 tcp_estimate_rtt_us (tc, rs->rtt_time);
487 mrtt = rs->rtt_time * THZ;
491 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
493 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
494 tcp_estimate_rtt_us (tc, sample);
495 mrtt = clib_max ((u32) (sample * THZ), 1);
496 /* Allow measuring of a new RTT */
499 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
500 * snd_una, i.e., the left side of the send window:
501 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
502 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
504 mrtt = clib_max (tcp_tstamp (tc) - tc->rcv_opts.tsecr, 1);
505 mrtt *= TCP_TSTP_TO_HZ;
510 /* Ignore dubious measurements */
511 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
514 tcp_estimate_rtt (tc, mrtt);
518 /* If we got here something must've been ACKed so make sure boff is 0,
519 * even if mrtt is not valid since we update the rto lower */
527 tcp_estimate_initial_rtt (tcp_connection_t * tc)
529 u8 thread_index = vlib_num_workers ()? 1 : 0;
534 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
535 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
536 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
541 mrtt = tcp_tstamp (tc) - tc->rcv_opts.tsecr;
542 mrtt = clib_max (mrtt, 1) * TCP_TSTP_TO_HZ;
543 /* Due to retransmits we don't know the initial mrtt */
544 if (tc->rto_boff && mrtt > 1 * THZ)
546 tc->mrtt_us = (f64) mrtt *TCP_TICK;
549 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
551 /* First measurement as per RFC 6298 */
553 tc->rttvar = mrtt >> 1;
559 * Dequeue bytes for connections that have received acks in last burst
562 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
564 u32 thread_index = wrk->vm->thread_index;
565 u32 *pending_deq_acked;
566 tcp_connection_t *tc;
569 if (!vec_len (wrk->pending_deq_acked))
572 pending_deq_acked = wrk->pending_deq_acked;
573 for (i = 0; i < vec_len (pending_deq_acked); i++)
575 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
576 tc->flags &= ~TCP_CONN_DEQ_PENDING;
578 if (PREDICT_FALSE (!tc->burst_acked))
581 /* Dequeue the newly ACKed bytes */
582 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
583 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
585 if (tcp_is_descheduled (tc))
588 /* If everything has been acked, stop retransmit timer
589 * otherwise update. */
590 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
592 /* Update pacer based on our new cwnd estimate */
593 tcp_connection_tx_pacer_update (tc);
597 _vec_len (wrk->pending_deq_acked) = 0;
601 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
603 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
605 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
606 tc->flags |= TCP_CONN_DEQ_PENDING;
608 tc->burst_acked += tc->bytes_acked;
612 * Try to update snd_wnd based on feedback received from peer.
614 * If successful, and new window is 'effectively' 0, activate persist
618 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
620 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
621 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
622 if (seq_lt (tc->snd_wl1, seq)
623 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
625 tc->snd_wnd = snd_wnd;
628 TCP_EVT (TCP_EVT_SND_WND, tc);
630 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
632 /* Set persist timer if not set and we just got 0 wnd */
633 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
634 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
636 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
637 tcp_persist_timer_set (&wrk->timer_wheel, tc);
642 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
644 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
645 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
648 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
651 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
661 * Init loss recovery/fast recovery.
663 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
664 * updated in @ref tcp_cc_handle_event after fast retransmit
667 tcp_cc_init_congestion (tcp_connection_t * tc)
669 tcp_fastrecovery_on (tc);
670 tc->snd_congestion = tc->snd_nxt;
671 tc->cwnd_acc_bytes = 0;
672 tc->snd_rxt_bytes = 0;
673 tc->rxt_delivered = 0;
674 tc->prr_delivered = 0;
675 tc->prr_start = tc->snd_una;
676 tc->prev_ssthresh = tc->ssthresh;
677 tc->prev_cwnd = tc->cwnd;
679 tc->snd_rxt_ts = tcp_tstamp (tc);
680 tcp_cc_congestion (tc);
682 /* Post retransmit update cwnd to ssthresh and account for the
683 * three segments that have left the network and should've been
684 * buffered at the receiver XXX */
685 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
686 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
688 tc->fr_occurences += 1;
689 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
693 tcp_cc_congestion_undo (tcp_connection_t * tc)
695 tc->cwnd = tc->prev_cwnd;
696 tc->ssthresh = tc->prev_ssthresh;
697 tcp_cc_undo_recovery (tc);
698 ASSERT (tc->rto_boff == 0);
699 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
703 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
705 return (tcp_in_recovery (tc) && tc->rto_boff == 1
707 && tcp_opts_tstamp (&tc->rcv_opts)
708 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
712 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
714 return (tcp_cc_is_spurious_timeout_rxt (tc));
718 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
722 /* If of of the two conditions lower hold, reset dupacks because
723 * we're probably after timeout (RFC6582 heuristics).
724 * If Cumulative ack does not cover more than congestion threshold,
726 * 1) The following doesn't hold: The congestion window is greater
727 * than SMSS bytes and the difference between highest_ack
728 * and prev_highest_ack is at most 4*SMSS bytes
729 * 2) Echoed timestamp in the last non-dup ack does not equal the
732 if (seq_leq (tc->snd_una, tc->snd_congestion)
733 && ((!(tc->cwnd > tc->snd_mss
734 && tc->bytes_acked <= 4 * tc->snd_mss))
735 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
741 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
745 tcp_cc_recover (tcp_connection_t * tc)
747 sack_scoreboard_hole_t *hole;
750 ASSERT (tcp_in_cong_recovery (tc));
752 if (tcp_cc_is_spurious_retransmit (tc))
754 tcp_cc_congestion_undo (tc);
758 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
761 /* Previous recovery left us congested. Continue sending as part
762 * of the current recovery event with an updated snd_congestion */
763 if (tc->sack_sb.sacked_bytes)
765 tc->snd_congestion = tc->snd_nxt;
766 tcp_program_retransmit (tc);
770 tc->rxt_delivered = 0;
771 tc->snd_rxt_bytes = 0;
773 tc->prr_delivered = 0;
775 tc->flags &= ~TCP_CONN_RXT_PENDING;
777 hole = scoreboard_first_hole (&tc->sack_sb);
778 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
779 scoreboard_clear (&tc->sack_sb);
781 if (!tcp_in_recovery (tc) && !is_spurious)
782 tcp_cc_recovered (tc);
784 tcp_fastrecovery_off (tc);
785 tcp_fastrecovery_first_off (tc);
786 tcp_recovery_off (tc);
787 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
789 ASSERT (tc->rto_boff == 0);
790 ASSERT (!tcp_in_cong_recovery (tc));
791 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
797 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
799 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
801 /* Congestion avoidance */
802 tcp_cc_rcv_ack (tc, rs);
804 /* If a cumulative ack, make sure dupacks is 0 */
807 /* When dupacks hits the threshold we only enter fast retransmit if
808 * cumulative ack covers more than snd_congestion. Should snd_una
809 * wrap this test may fail under otherwise valid circumstances.
810 * Therefore, proactively update snd_congestion when wrap detected. */
812 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
813 && seq_gt (tc->snd_congestion, tc->snd_una)))
814 tc->snd_congestion = tc->snd_una - 1;
818 * One function to rule them all ... and in the darkness bind them
821 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
824 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
826 /* If reneging, wait for timer based retransmits */
827 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
831 * If not in recovery, figure out if we should enter
833 if (!tcp_in_cong_recovery (tc))
838 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
839 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
841 if (tcp_should_fastrecover (tc, has_sack))
843 tcp_cc_init_congestion (tc);
846 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
848 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
849 tcp_program_retransmit (tc);
856 * Already in recovery
860 * Process (re)transmit feedback. Output path uses this to decide how much
861 * more data to release into the network
865 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
866 tcp_fastrecovery_first_on (tc);
868 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
869 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
870 - tc->sack_sb.last_bytes_delivered;
876 tc->rcv_dupacks += 1;
877 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
879 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
882 tc->prr_delivered += clib_min (tc->snd_mss,
883 tc->snd_nxt - tc->snd_una);
885 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
889 /* If partial ack, assume that the first un-acked segment was lost */
890 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
891 tcp_fastrecovery_first_on (tc);
895 * See if we can exit and stop retransmitting
897 if (seq_geq (tc->snd_una, tc->snd_congestion))
899 /* If spurious return, we've already updated everything */
900 if (tcp_cc_recover (tc))
902 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
906 /* Treat as congestion avoidance ack */
907 tcp_cc_rcv_ack (tc, rs);
911 tcp_program_retransmit (tc);
914 * Notify cc of the event
917 if (!tc->bytes_acked)
919 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
923 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
924 * reset dupacks to 0. Also needed if in congestion recovery */
927 if (tcp_in_recovery (tc))
928 tcp_cc_rcv_ack (tc, rs);
930 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
934 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
936 if (!tcp_in_cong_recovery (tc))
939 if (tcp_opts_sack_permitted (&tc->rcv_opts))
940 tcp_rcv_sacks (tc, tc->snd_una);
944 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
945 tcp_bt_sample_delivery_rate (tc, rs);
947 tcp_cc_handle_event (tc, rs, 1);
951 * Check if duplicate ack as per RFC5681 Sec. 2
954 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
957 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
958 && seq_gt (tc->snd_nxt, tc->snd_una)
959 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
960 && (prev_snd_wnd == tc->snd_wnd));
964 * Checks if ack is a congestion control event.
967 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
968 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
970 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
971 * defined to be 'duplicate' as well */
972 *is_dack = tc->sack_sb.last_sacked_bytes
973 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
975 return (*is_dack || tcp_in_cong_recovery (tc));
979 * Process incoming ACK
982 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
983 tcp_header_t * th, u32 * error)
985 u32 prev_snd_wnd, prev_snd_una;
986 tcp_rate_sample_t rs = { 0 };
989 TCP_EVT (TCP_EVT_CC_STAT, tc);
991 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
992 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
994 /* We've probably entered recovery and the peer still has some
995 * of the data we've sent. Update snd_nxt and accept the ack */
996 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
997 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
999 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1003 tc->errors.above_ack_wnd += 1;
1004 *error = TCP_ERROR_ACK_FUTURE;
1005 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1009 /* If old ACK, probably it's an old dupack */
1010 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1012 tc->errors.below_ack_wnd += 1;
1013 *error = TCP_ERROR_ACK_OLD;
1014 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1016 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1019 tcp_handle_old_ack (tc, &rs);
1021 /* Don't drop yet */
1028 * Looks okay, process feedback
1031 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1032 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1034 prev_snd_wnd = tc->snd_wnd;
1035 prev_snd_una = tc->snd_una;
1036 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1037 vnet_buffer (b)->tcp.ack_number,
1038 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1039 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1040 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1041 tcp_validate_txf_size (tc, tc->bytes_acked);
1043 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1044 tcp_bt_sample_delivery_rate (tc, &rs);
1046 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1048 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1049 if (tc->bytes_acked)
1050 tcp_program_dequeue (wrk, tc);
1053 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1056 * Check if we have congestion event
1059 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1061 tcp_cc_handle_event (tc, &rs, is_dack);
1062 tc->dupacks_in += is_dack;
1063 if (!tcp_in_cong_recovery (tc))
1065 *error = TCP_ERROR_ACK_OK;
1068 *error = TCP_ERROR_ACK_DUP;
1069 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1075 * Update congestion control (slow start/congestion avoidance)
1077 tcp_cc_update (tc, &rs);
1078 *error = TCP_ERROR_ACK_OK;
1083 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1085 if (!tcp_disconnect_pending (tc))
1087 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1088 tcp_disconnect_pending_on (tc);
1093 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1095 u32 thread_index, *pending_disconnects, *pending_resets;
1096 tcp_connection_t *tc;
1099 if (vec_len (wrk->pending_disconnects))
1101 thread_index = wrk->vm->thread_index;
1102 pending_disconnects = wrk->pending_disconnects;
1103 for (i = 0; i < vec_len (pending_disconnects); i++)
1105 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1106 tcp_disconnect_pending_off (tc);
1107 session_transport_closing_notify (&tc->connection);
1109 _vec_len (wrk->pending_disconnects) = 0;
1112 if (vec_len (wrk->pending_resets))
1114 thread_index = wrk->vm->thread_index;
1115 pending_resets = wrk->pending_resets;
1116 for (i = 0; i < vec_len (pending_resets); i++)
1118 tc = tcp_connection_get (pending_resets[i], thread_index);
1119 tcp_disconnect_pending_off (tc);
1120 tcp_handle_rst (tc);
1122 _vec_len (wrk->pending_resets) = 0;
1127 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1130 /* Reject out-of-order fins */
1131 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1134 /* Account for the FIN and send ack */
1136 tc->flags |= TCP_CONN_FINRCVD;
1137 tcp_program_ack (tc);
1138 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1139 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1140 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1141 tcp_program_disconnect (wrk, tc);
1142 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1143 tcp_cfg.closewait_time);
1144 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1145 *error = TCP_ERROR_FIN_RCVD;
1148 /** Enqueue data for delivery to application */
1150 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1153 int written, error = TCP_ERROR_ENQUEUED;
1155 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1157 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1158 1 /* queue event */ , 1);
1159 tc->bytes_in += written;
1161 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1163 /* Update rcv_nxt */
1164 if (PREDICT_TRUE (written == data_len))
1166 tc->rcv_nxt += written;
1168 /* If more data written than expected, account for out-of-order bytes. */
1169 else if (written > data_len)
1171 tc->rcv_nxt += written;
1172 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1174 else if (written > 0)
1176 /* We've written something but FIFO is probably full now */
1177 tc->rcv_nxt += written;
1178 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1182 /* Packet made it through for ack processing */
1183 if (tc->rcv_wnd < tc->snd_mss)
1184 return TCP_ERROR_ZERO_RWND;
1186 return TCP_ERROR_FIFO_FULL;
1189 /* Update SACK list if need be */
1190 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1192 /* Remove SACK blocks that have been delivered */
1193 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1199 /** Enqueue out-of-order data */
1201 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1207 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1210 /* Enqueue out-of-order data with relative offset */
1211 rv = session_enqueue_stream_connection (&tc->connection, b,
1212 vnet_buffer (b)->tcp.seq_number -
1213 tc->rcv_nxt, 0 /* queue event */ ,
1216 /* Nothing written */
1219 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1220 return TCP_ERROR_FIFO_FULL;
1223 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1224 tc->bytes_in += data_len;
1226 /* Update SACK list if in use */
1227 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1229 ooo_segment_t *newest;
1232 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1234 /* Get the newest segment from the fifo */
1235 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1238 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1239 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1240 start = tc->rcv_nxt + offset;
1241 end = start + ooo_segment_length (s0->rx_fifo, newest);
1242 tcp_update_sack_list (tc, start, end);
1243 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1244 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1248 return TCP_ERROR_ENQUEUED_OOO;
1252 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1254 u32 discard, first = b->current_length;
1255 vlib_main_t *vm = vlib_get_main ();
1257 /* Handle multi-buffer segments */
1258 if (n_bytes_to_drop > b->current_length)
1260 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1264 discard = clib_min (n_bytes_to_drop, b->current_length);
1265 vlib_buffer_advance (b, discard);
1266 b = vlib_get_buffer (vm, b->next_buffer);
1267 n_bytes_to_drop -= discard;
1269 while (n_bytes_to_drop);
1270 if (n_bytes_to_drop > first)
1271 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1274 vlib_buffer_advance (b, n_bytes_to_drop);
1275 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1280 * Receive buffer for connection and handle acks
1282 * It handles both in order or out-of-order data.
1285 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1288 u32 error, n_bytes_to_drop, n_data_bytes;
1290 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1291 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1292 ASSERT (n_data_bytes);
1293 tc->data_segs_in += 1;
1295 /* Make sure we don't consume trailing bytes */
1296 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1297 b->current_length = n_data_bytes;
1299 /* Handle out-of-order data */
1300 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1302 /* Old sequence numbers allowed through because they overlapped
1304 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1306 /* Completely in the past (possible retransmit). Ack
1307 * retransmissions since we may not have any data to send */
1308 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1310 tcp_program_dupack (tc);
1311 tc->errors.below_data_wnd++;
1312 error = TCP_ERROR_SEGMENT_OLD;
1316 /* Chop off the bytes in the past and see if what is left
1317 * can be enqueued in order */
1318 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1319 n_data_bytes -= n_bytes_to_drop;
1320 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1321 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1323 error = TCP_ERROR_SEGMENT_OLD;
1329 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1330 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1331 tcp_program_dupack (tc);
1332 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1333 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1334 tc->rcv_las + tc->rcv_wnd);
1340 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1341 * segments can be enqueued after fifo tail offset changes. */
1342 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1343 tcp_program_ack (tc);
1351 tcp_header_t tcp_header;
1352 tcp_connection_t tcp_connection;
1356 format_tcp_rx_trace (u8 * s, va_list * args)
1358 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1359 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1360 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1361 tcp_connection_t *tc = &t->tcp_connection;
1362 u32 indent = format_get_indent (s);
1364 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1365 format_tcp_state, tc->state, format_white_space, indent,
1366 format_tcp_header, &t->tcp_header, 128);
1372 format_tcp_rx_trace_short (u8 * s, va_list * args)
1374 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1375 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1376 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1378 s = format (s, "%d -> %d (%U)",
1379 clib_net_to_host_u16 (t->tcp_header.dst_port),
1380 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1381 t->tcp_connection.state);
1387 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1388 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1392 clib_memcpy_fast (&t0->tcp_connection, tc0,
1393 sizeof (t0->tcp_connection));
1397 th0 = tcp_buffer_hdr (b0);
1399 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1403 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1404 vlib_frame_t * frame, u8 is_ip4)
1408 n_left = frame->n_vectors;
1409 from = vlib_frame_vector_args (frame);
1413 tcp_connection_t *tc0;
1420 b0 = vlib_get_buffer (vm, bi0);
1422 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1424 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1425 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1427 th0 = tcp_buffer_hdr (b0);
1428 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1437 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1438 u8 is_ip4, u32 evt, u32 val)
1441 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1443 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1446 #define tcp_maybe_inc_counter(node_id, err, count) \
1448 if (next0 != tcp_next_drop (is_ip4)) \
1449 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1450 tcp6_##node_id##_node.index, is_ip4, err, \
1453 #define tcp_inc_counter(node_id, err, count) \
1454 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1455 tcp6_##node_id##_node.index, is_ip4, \
1457 #define tcp_maybe_inc_err_counter(cnts, err) \
1459 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1461 #define tcp_inc_err_counter(cnts, err, val) \
1465 #define tcp_store_err_counters(node_id, cnts) \
1468 for (i = 0; i < TCP_N_ERROR; i++) \
1470 tcp_inc_counter(node_id, i, cnts[i]); \
1475 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1476 vlib_frame_t * frame, int is_ip4)
1478 u32 thread_index = vm->thread_index, errors = 0;
1479 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1480 u32 n_left_from, *from, *first_buffer;
1481 u16 err_counters[TCP_N_ERROR] = { 0 };
1483 if (node->flags & VLIB_NODE_FLAG_TRACE)
1484 tcp_established_trace_frame (vm, node, frame, is_ip4);
1486 first_buffer = from = vlib_frame_vector_args (frame);
1487 n_left_from = frame->n_vectors;
1489 while (n_left_from > 0)
1491 u32 bi0, error0 = TCP_ERROR_ACK_OK;
1494 tcp_connection_t *tc0;
1496 if (n_left_from > 1)
1499 pb = vlib_get_buffer (vm, from[1]);
1500 vlib_prefetch_buffer_header (pb, LOAD);
1501 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1508 b0 = vlib_get_buffer (vm, bi0);
1509 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1512 if (PREDICT_FALSE (tc0 == 0))
1514 error0 = TCP_ERROR_INVALID_CONNECTION;
1518 th0 = tcp_buffer_hdr (b0);
1520 /* TODO header prediction fast path */
1522 /* 1-4: check SEQ, RST, SYN */
1523 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
1525 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
1529 /* 5: check the ACK field */
1530 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
1533 /* 6: check the URG bit TODO */
1535 /* 7: process the segment text */
1536 if (vnet_buffer (b0)->tcp.data_len)
1537 error0 = tcp_segment_rcv (wrk, tc0, b0);
1539 /* 8: check the FIN bit */
1540 if (PREDICT_FALSE (tcp_is_fin (th0)))
1541 tcp_rcv_fin (wrk, tc0, b0, &error0);
1544 tcp_inc_err_counter (err_counters, error0, 1);
1547 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1549 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1550 tcp_store_err_counters (established, err_counters);
1551 tcp_handle_postponed_dequeues (wrk);
1552 tcp_handle_disconnects (wrk);
1553 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
1555 return frame->n_vectors;
1558 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1559 vlib_node_runtime_t * node,
1560 vlib_frame_t * from_frame)
1562 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1565 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1566 vlib_node_runtime_t * node,
1567 vlib_frame_t * from_frame)
1569 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1573 VLIB_REGISTER_NODE (tcp4_established_node) =
1575 .name = "tcp4-established",
1576 /* Takes a vector of packets. */
1577 .vector_size = sizeof (u32),
1578 .n_errors = TCP_N_ERROR,
1579 .error_strings = tcp_error_strings,
1580 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1583 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1584 foreach_tcp_state_next
1587 .format_trace = format_tcp_rx_trace_short,
1592 VLIB_REGISTER_NODE (tcp6_established_node) =
1594 .name = "tcp6-established",
1595 /* Takes a vector of packets. */
1596 .vector_size = sizeof (u32),
1597 .n_errors = TCP_N_ERROR,
1598 .error_strings = tcp_error_strings,
1599 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1602 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1603 foreach_tcp_state_next
1606 .format_trace = format_tcp_rx_trace_short,
1612 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1615 transport_connection_t *tmp = 0;
1622 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1625 u8 is_ip_valid = 0, val_l, val_r;
1627 if (tc->connection.is_ip4)
1629 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1631 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1632 &tc->connection.lcl_ip.ip4);
1633 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1634 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1635 &tc->connection.rmt_ip.ip4);
1636 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1637 is_ip_valid = val_l && val_r;
1641 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1643 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1644 &tc->connection.lcl_ip.ip6);
1645 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1646 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1647 &tc->connection.rmt_ip.ip6);
1648 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1649 is_ip_valid = val_l && val_r;
1652 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1653 && (tc->state == TCP_STATE_LISTEN
1654 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1658 handle = session_lookup_half_open_handle (&tc->connection);
1659 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1660 tc->c_proto, tc->c_is_ip4);
1664 if (tmp->lcl_port == hdr->dst_port
1665 && tmp->rmt_port == hdr->src_port)
1667 TCP_DBG ("half-open is valid!");
1676 * Lookup transport connection
1678 static tcp_connection_t *
1679 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1683 transport_connection_t *tconn;
1684 tcp_connection_t *tc;
1689 ip4 = vlib_buffer_get_current (b);
1690 tcp = ip4_next_header (ip4);
1691 tconn = session_lookup_connection_wt4 (fib_index,
1696 TRANSPORT_PROTO_TCP,
1697 thread_index, &is_filtered);
1698 tc = tcp_get_connection_from_transport (tconn);
1699 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1704 ip6 = vlib_buffer_get_current (b);
1705 tcp = ip6_next_header (ip6);
1706 tconn = session_lookup_connection_wt6 (fib_index,
1711 TRANSPORT_PROTO_TCP,
1712 thread_index, &is_filtered);
1713 tc = tcp_get_connection_from_transport (tconn);
1714 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1719 static tcp_connection_t *
1720 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1726 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1727 tcp_header_t *tcp = tcp_buffer_hdr (b);
1728 s = session_lookup_listener4 (fib_index,
1730 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1734 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1735 tcp_header_t *tcp = tcp_buffer_hdr (b);
1736 s = session_lookup_listener6 (fib_index,
1738 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1741 if (PREDICT_TRUE (s != 0))
1742 return tcp_get_connection_from_transport (transport_get_listener
1743 (TRANSPORT_PROTO_TCP,
1744 s->connection_index));
1750 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1752 vnet_main_t *vnm = vnet_get_main ();
1753 const dpo_id_t *dpo;
1754 const load_balance_t *lb;
1755 vnet_hw_interface_t *hw_if;
1756 u32 sw_if_idx, lb_idx;
1760 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1761 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1765 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1766 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1769 lb = load_balance_get (lb_idx);
1770 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1772 dpo = load_balance_get_bucket_i (lb, 0);
1774 sw_if_idx = dpo_get_urpf (dpo);
1775 if (PREDICT_FALSE (sw_if_idx == ~0))
1778 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1779 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
1780 tc->cfg_flags |= TCP_CFG_F_TSO;
1784 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1785 vlib_frame_t * from_frame, int is_ip4)
1787 u32 n_left_from, *from, *first_buffer, errors = 0;
1788 u32 my_thread_index = vm->thread_index;
1789 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
1791 from = first_buffer = vlib_frame_vector_args (from_frame);
1792 n_left_from = from_frame->n_vectors;
1794 while (n_left_from > 0)
1796 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
1797 tcp_connection_t *tc0, *new_tc0;
1798 tcp_header_t *tcp0 = 0;
1806 b0 = vlib_get_buffer (vm, bi0);
1808 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
1809 if (PREDICT_FALSE (tc0 == 0))
1811 error0 = TCP_ERROR_INVALID_CONNECTION;
1815 /* Half-open completed recently but the connection was't removed
1816 * yet by the owning thread */
1817 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1819 /* Make sure the connection actually exists */
1820 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
1821 my_thread_index, is_ip4));
1822 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
1826 ack0 = vnet_buffer (b0)->tcp.ack_number;
1827 seq0 = vnet_buffer (b0)->tcp.seq_number;
1828 tcp0 = tcp_buffer_hdr (b0);
1830 /* Crude check to see if the connection handle does not match
1831 * the packet. Probably connection just switched to established */
1832 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1833 || tcp0->src_port != tc0->c_rmt_port))
1835 error0 = TCP_ERROR_INVALID_CONNECTION;
1839 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
1840 && !tcp_syn (tcp0)))
1842 error0 = TCP_ERROR_SEGMENT_INVALID;
1846 /* SYNs consume sequence numbers */
1847 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
1850 * 1. check the ACK bit
1854 * If the ACK bit is set
1855 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1856 * the RST bit is set, if so drop the segment and return)
1857 * <SEQ=SEG.ACK><CTL=RST>
1858 * and discard the segment. Return.
1859 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1863 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
1865 if (!tcp_rst (tcp0))
1866 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1867 error0 = TCP_ERROR_RCV_WND;
1871 /* Make sure ACK is valid */
1872 if (seq_gt (tc0->snd_una, ack0))
1874 error0 = TCP_ERROR_ACK_INVALID;
1880 * 2. check the RST bit
1885 /* If ACK is acceptable, signal client that peer is not
1886 * willing to accept connection and drop connection*/
1888 tcp_rcv_rst (wrk, tc0);
1889 error0 = TCP_ERROR_RST_RCVD;
1894 * 3. check the security and precedence (skipped)
1898 * 4. check the SYN bit
1901 /* No SYN flag. Drop. */
1902 if (!tcp_syn (tcp0))
1904 error0 = TCP_ERROR_SEGMENT_INVALID;
1909 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
1911 error0 = TCP_ERROR_OPTIONS;
1915 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1916 * current thread pool. */
1917 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
1918 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
1919 new_tc0->irs = seq0;
1920 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1921 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1923 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
1925 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
1926 new_tc0->tsval_recent_age = tcp_time_now ();
1929 if (tcp_opts_wscale (&new_tc0->rcv_opts))
1930 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
1932 new_tc0->rcv_wscale = 0;
1934 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
1935 << new_tc0->snd_wscale;
1936 new_tc0->snd_wl1 = seq0;
1937 new_tc0->snd_wl2 = ack0;
1939 tcp_connection_init_vars (new_tc0);
1941 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1942 if (PREDICT_TRUE (tcp_ack (tcp0)))
1944 /* Our SYN is ACKed: we have iss < ack = snd_una */
1946 /* TODO Dequeue acknowledged segments if we support Fast Open */
1947 new_tc0->snd_una = ack0;
1948 new_tc0->state = TCP_STATE_ESTABLISHED;
1950 /* Make sure las is initialized for the wnd computation */
1951 new_tc0->rcv_las = new_tc0->rcv_nxt;
1953 /* Notify app that we have connection. If session layer can't
1954 * allocate session send reset */
1955 if (session_stream_connect_notify (&new_tc0->connection,
1958 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
1959 tcp_connection_cleanup (new_tc0);
1960 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1964 transport_fifos_init_ooo (&new_tc0->connection);
1965 new_tc0->tx_fifo_size =
1966 transport_tx_fifo_size (&new_tc0->connection);
1967 /* Update rtt with the syn-ack sample */
1968 tcp_estimate_initial_rtt (new_tc0);
1969 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
1970 error0 = TCP_ERROR_SYN_ACKS_RCVD;
1972 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1975 new_tc0->state = TCP_STATE_SYN_RCVD;
1977 /* Notify app that we have connection */
1978 if (session_stream_connect_notify (&new_tc0->connection,
1981 tcp_connection_cleanup (new_tc0);
1982 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1983 TCP_EVT (TCP_EVT_RST_SENT, tc0);
1984 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1988 transport_fifos_init_ooo (&new_tc0->connection);
1989 new_tc0->tx_fifo_size =
1990 transport_tx_fifo_size (&new_tc0->connection);
1991 new_tc0->rtt_ts = 0;
1992 tcp_init_snd_vars (new_tc0);
1993 tcp_send_synack (new_tc0);
1994 error0 = TCP_ERROR_SYNS_RCVD;
1998 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
1999 tcp_check_tx_offload (new_tc0, is_ip4);
2001 /* Read data, if any */
2002 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2004 clib_warning ("rcvd data in syn-sent");
2005 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2006 if (error0 == TCP_ERROR_ACK_OK)
2007 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2011 /* Send ack now instead of programming it because connection was
2012 * just established and it's not optional. */
2013 tcp_send_ack (new_tc0);
2018 /* If this is not the owning thread, wait for syn retransmit to
2019 * expire and cleanup then */
2020 if (tcp_half_open_connection_cleanup (tc0))
2021 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2025 tcp_inc_counter (syn_sent, error0, 1);
2026 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2028 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2029 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2030 clib_memcpy_fast (&t0->tcp_connection, tc0,
2031 sizeof (t0->tcp_connection));
2035 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2037 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2038 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2039 tcp_handle_disconnects (wrk);
2041 return from_frame->n_vectors;
2044 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2045 vlib_node_runtime_t * node,
2046 vlib_frame_t * from_frame)
2048 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2051 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2052 vlib_node_runtime_t * node,
2053 vlib_frame_t * from_frame)
2055 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2059 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2061 .name = "tcp4-syn-sent",
2062 /* Takes a vector of packets. */
2063 .vector_size = sizeof (u32),
2064 .n_errors = TCP_N_ERROR,
2065 .error_strings = tcp_error_strings,
2066 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2069 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2070 foreach_tcp_state_next
2073 .format_trace = format_tcp_rx_trace_short,
2078 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2080 .name = "tcp6-syn-sent",
2081 /* Takes a vector of packets. */
2082 .vector_size = sizeof (u32),
2083 .n_errors = TCP_N_ERROR,
2084 .error_strings = tcp_error_strings,
2085 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2088 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2089 foreach_tcp_state_next
2092 .format_trace = format_tcp_rx_trace_short,
2097 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2098 * as per RFC793 p. 64
2101 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2102 vlib_frame_t * from_frame, int is_ip4)
2104 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2105 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2106 u32 n_left_from, *from, max_dequeue;
2108 from = first_buffer = vlib_frame_vector_args (from_frame);
2109 n_left_from = from_frame->n_vectors;
2111 while (n_left_from > 0)
2113 u32 bi0, error0 = TCP_ERROR_NONE;
2114 tcp_header_t *tcp0 = 0;
2115 tcp_connection_t *tc0;
2123 b0 = vlib_get_buffer (vm, bi0);
2124 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2126 if (PREDICT_FALSE (tc0 == 0))
2128 error0 = TCP_ERROR_INVALID_CONNECTION;
2132 tcp0 = tcp_buffer_hdr (b0);
2133 is_fin0 = tcp_is_fin (tcp0);
2137 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2139 tcp_connection_t *tmp;
2140 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2142 if (tmp->state != tc0->state)
2144 if (tc0->state != TCP_STATE_CLOSED)
2145 clib_warning ("state changed");
2152 * Special treatment for CLOSED
2154 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2156 error0 = TCP_ERROR_CONNECTION_CLOSED;
2161 * For all other states (except LISTEN)
2164 /* 1-4: check SEQ, RST, SYN */
2165 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2168 /* 5: check the ACK field */
2171 case TCP_STATE_SYN_RCVD:
2173 /* Make sure the segment is exactly right */
2174 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2176 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2177 error0 = TCP_ERROR_SEGMENT_INVALID;
2182 * If the segment acknowledgment is not acceptable, form a
2184 * <SEQ=SEG.ACK><CTL=RST>
2187 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2189 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2190 error0 = TCP_ERROR_SEGMENT_INVALID;
2194 /* Update rtt and rto */
2195 tcp_estimate_initial_rtt (tc0);
2196 tcp_connection_tx_pacer_update (tc0);
2198 /* Switch state to ESTABLISHED */
2199 tc0->state = TCP_STATE_ESTABLISHED;
2200 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2202 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2203 tcp_check_tx_offload (tc0, is_ip4);
2205 /* Initialize session variables */
2206 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2207 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2208 << tc0->rcv_opts.wscale;
2209 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2210 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2212 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2213 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc0);
2214 if (session_stream_accept_notify (&tc0->connection))
2216 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2217 tcp_send_reset (tc0);
2218 session_transport_delete_notify (&tc0->connection);
2219 tcp_connection_cleanup (tc0);
2222 error0 = TCP_ERROR_ACK_OK;
2224 case TCP_STATE_ESTABLISHED:
2225 /* We can get packets in established state here because they
2226 * were enqueued before state change */
2227 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2231 case TCP_STATE_FIN_WAIT_1:
2232 /* In addition to the processing for the ESTABLISHED state, if
2233 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2234 * continue processing in that state. */
2235 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2238 /* Still have to send the FIN */
2239 if (tc0->flags & TCP_CONN_FINPNDG)
2241 /* TX fifo finally drained */
2242 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2243 if (max_dequeue <= tc0->burst_acked)
2245 /* If a fin was received and data was acked extend wait */
2246 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2247 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2248 tcp_cfg.closewait_time);
2250 /* If FIN is ACKed */
2251 else if (tc0->snd_una == tc0->snd_nxt)
2253 /* Stop all retransmit timers because we have nothing more
2255 tcp_connection_timers_reset (tc0);
2257 /* We already have a FIN but didn't transition to CLOSING
2258 * because of outstanding tx data. Close the connection. */
2259 if (tc0->flags & TCP_CONN_FINRCVD)
2261 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2262 session_transport_closed_notify (&tc0->connection);
2263 tcp_program_cleanup (wrk, tc0);
2267 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2268 /* Enable waitclose because we're willing to wait for peer's
2269 * FIN but not indefinitely. */
2270 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2271 tcp_cfg.finwait2_time);
2273 /* Don't try to deq the FIN acked */
2274 if (tc0->burst_acked > 1)
2275 session_tx_fifo_dequeue_drop (&tc0->connection,
2276 tc0->burst_acked - 1);
2277 tc0->burst_acked = 0;
2280 case TCP_STATE_FIN_WAIT_2:
2281 /* In addition to the processing for the ESTABLISHED state, if
2282 * the retransmission queue is empty, the user's CLOSE can be
2283 * acknowledged ("ok") but do not delete the TCB. */
2284 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2286 tc0->burst_acked = 0;
2288 case TCP_STATE_CLOSE_WAIT:
2289 /* Do the same processing as for the ESTABLISHED state. */
2290 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2293 if (!(tc0->flags & TCP_CONN_FINPNDG))
2296 /* Still have outstanding tx data */
2297 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2298 if (max_dequeue > tc0->burst_acked)
2302 tcp_connection_timers_reset (tc0);
2303 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2304 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2305 tcp_cfg.lastack_time);
2307 case TCP_STATE_CLOSING:
2308 /* In addition to the processing for the ESTABLISHED state, if
2309 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2310 * otherwise ignore the segment. */
2311 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2314 if (tc0->snd_una != tc0->snd_nxt)
2317 tcp_connection_timers_reset (tc0);
2318 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2319 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2320 tcp_cfg.timewait_time);
2321 session_transport_closed_notify (&tc0->connection);
2325 case TCP_STATE_LAST_ACK:
2326 /* The only thing that [should] arrive in this state is an
2327 * acknowledgment of our FIN. If our FIN is now acknowledged,
2328 * delete the TCB, enter the CLOSED state, and return. */
2330 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2333 /* Apparently our ACK for the peer's FIN was lost */
2334 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2340 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2341 session_transport_closed_notify (&tc0->connection);
2343 /* Don't free the connection from the data path since
2344 * we can't ensure that we have no packets already enqueued
2345 * to output. Rely instead on the waitclose timer */
2346 tcp_connection_timers_reset (tc0);
2347 tcp_program_cleanup (tcp_get_worker (tc0->c_thread_index), tc0);
2352 case TCP_STATE_TIME_WAIT:
2353 /* The only thing that can arrive in this state is a
2354 * retransmission of the remote FIN. Acknowledge it, and restart
2355 * the 2 MSL timeout. */
2357 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2363 tcp_program_ack (tc0);
2364 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2365 tcp_cfg.timewait_time);
2373 /* 6: check the URG bit TODO */
2375 /* 7: process the segment text */
2378 case TCP_STATE_ESTABLISHED:
2379 case TCP_STATE_FIN_WAIT_1:
2380 case TCP_STATE_FIN_WAIT_2:
2381 if (vnet_buffer (b0)->tcp.data_len)
2382 error0 = tcp_segment_rcv (wrk, tc0, b0);
2383 /* Don't accept out of order fins lower */
2384 if (vnet_buffer (b0)->tcp.seq_end != tc0->rcv_nxt)
2387 case TCP_STATE_CLOSE_WAIT:
2388 case TCP_STATE_CLOSING:
2389 case TCP_STATE_LAST_ACK:
2390 case TCP_STATE_TIME_WAIT:
2391 /* This should not occur, since a FIN has been received from the
2392 * remote side. Ignore the segment text. */
2396 /* 8: check the FIN bit */
2400 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
2404 case TCP_STATE_ESTABLISHED:
2405 /* Account for the FIN and send ack */
2407 tcp_program_ack (tc0);
2408 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
2409 tcp_program_disconnect (wrk, tc0);
2410 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2411 tcp_cfg.closewait_time);
2413 case TCP_STATE_SYN_RCVD:
2414 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2415 * notified yet, set a cleanup timer instead of relying on
2416 * disconnect notify and the implicit close call. */
2417 tcp_connection_timers_reset (tc0);
2420 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2421 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2422 tcp_cfg.lastack_time);
2424 case TCP_STATE_CLOSE_WAIT:
2425 case TCP_STATE_CLOSING:
2426 case TCP_STATE_LAST_ACK:
2429 case TCP_STATE_FIN_WAIT_1:
2432 if (tc0->flags & TCP_CONN_FINPNDG)
2434 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2435 * sending it. Since we already received a fin, do not wait
2437 tc0->flags |= TCP_CONN_FINRCVD;
2438 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2439 tcp_cfg.closewait_time);
2443 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2444 tcp_program_ack (tc0);
2445 /* Wait for ACK for our FIN but not forever */
2446 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2447 tcp_cfg.closing_time);
2450 case TCP_STATE_FIN_WAIT_2:
2451 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2453 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2454 tcp_connection_timers_reset (tc0);
2455 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2456 tcp_cfg.timewait_time);
2457 tcp_program_ack (tc0);
2458 session_transport_closed_notify (&tc0->connection);
2460 case TCP_STATE_TIME_WAIT:
2461 /* Remain in the TIME-WAIT state. Restart the time-wait
2464 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2465 tcp_cfg.timewait_time);
2468 error0 = TCP_ERROR_FIN_RCVD;
2472 tcp_inc_counter (rcv_process, error0, 1);
2473 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2475 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2476 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2480 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2482 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2483 tcp_handle_postponed_dequeues (wrk);
2484 tcp_handle_disconnects (wrk);
2485 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2487 return from_frame->n_vectors;
2490 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2491 vlib_node_runtime_t * node,
2492 vlib_frame_t * from_frame)
2494 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2497 VLIB_NODE_FN (tcp6_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, 0 /* is_ip4 */ );
2505 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2507 .name = "tcp4-rcv-process",
2508 /* Takes a vector of packets. */
2509 .vector_size = sizeof (u32),
2510 .n_errors = TCP_N_ERROR,
2511 .error_strings = tcp_error_strings,
2512 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2515 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2516 foreach_tcp_state_next
2519 .format_trace = format_tcp_rx_trace_short,
2524 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2526 .name = "tcp6-rcv-process",
2527 /* Takes a vector of packets. */
2528 .vector_size = sizeof (u32),
2529 .n_errors = TCP_N_ERROR,
2530 .error_strings = tcp_error_strings,
2531 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2534 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2535 foreach_tcp_state_next
2538 .format_trace = format_tcp_rx_trace_short,
2543 * LISTEN state processing as per RFC 793 p. 65
2546 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2547 vlib_frame_t * from_frame, int is_ip4)
2549 u32 n_left_from, *from, n_syns = 0, *first_buffer;
2550 u32 thread_index = vm->thread_index;
2552 from = first_buffer = vlib_frame_vector_args (from_frame);
2553 n_left_from = from_frame->n_vectors;
2555 while (n_left_from > 0)
2557 u32 bi, error = TCP_ERROR_NONE;
2558 tcp_connection_t *lc, *child;
2565 b = vlib_get_buffer (vm, bi);
2567 lc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2568 if (PREDICT_FALSE (lc == 0))
2570 tcp_connection_t *tc;
2571 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2573 if (tc->state != TCP_STATE_TIME_WAIT)
2575 error = TCP_ERROR_CREATE_EXISTS;
2578 lc = tcp_lookup_listener (b, tc->c_fib_index, is_ip4);
2579 /* clean up the old session */
2580 tcp_connection_del (tc);
2581 /* listener was cleaned up */
2584 error = TCP_ERROR_NO_LISTENER;
2589 /* Make sure connection wasn't just created */
2590 child = tcp_lookup_connection (lc->c_fib_index, b, thread_index,
2592 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2594 error = TCP_ERROR_CREATE_EXISTS;
2598 /* Create child session. For syn-flood protection use filter */
2600 /* 1. first check for an RST: handled in dispatch */
2601 /* if (tcp_rst (th0))
2605 /* 2. second check for an ACK: handled in dispatch */
2606 /* if (tcp_ack (th0))
2608 tcp_send_reset (b0, is_ip4);
2613 /* 3. check for a SYN (did that already) */
2615 /* Create child session and send SYN-ACK */
2616 child = tcp_connection_alloc (thread_index);
2618 if (tcp_options_parse (tcp_buffer_hdr (b), &child->rcv_opts, 1))
2620 error = TCP_ERROR_OPTIONS;
2621 tcp_connection_free (child);
2625 tcp_init_w_buffer (child, b, is_ip4);
2627 child->state = TCP_STATE_SYN_RCVD;
2628 child->c_fib_index = lc->c_fib_index;
2629 child->cc_algo = lc->cc_algo;
2630 tcp_connection_init_vars (child);
2631 child->rto = TCP_RTO_MIN;
2634 * This initializes elog track, must be done before synack.
2635 * We also do it before possible tcp_connection_cleanup() as it
2636 * generates TCP_EVT_DELETE event.
2638 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2640 if (session_stream_accept (&child->connection, lc->c_s_index,
2641 lc->c_thread_index, 0 /* notify */ ))
2643 tcp_connection_cleanup (child);
2644 error = TCP_ERROR_CREATE_SESSION_FAIL;
2648 transport_fifos_init_ooo (&child->connection);
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))
2657 tcp_rx_trace_t *t = vlib_add_trace (vm, node, b, sizeof (*t));
2658 tcp_set_rx_trace_data (t, lc, tcp_buffer_hdr (b), b, is_ip4);
2661 n_syns += (error == TCP_ERROR_NONE);
2664 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2665 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2667 return from_frame->n_vectors;
2670 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2671 vlib_frame_t * from_frame)
2673 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2676 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2677 vlib_frame_t * from_frame)
2679 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2683 VLIB_REGISTER_NODE (tcp4_listen_node) =
2685 .name = "tcp4-listen",
2686 /* Takes a vector of packets. */
2687 .vector_size = sizeof (u32),
2688 .n_errors = TCP_N_ERROR,
2689 .error_strings = tcp_error_strings,
2690 .n_next_nodes = TCP_LISTEN_N_NEXT,
2693 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2694 foreach_tcp_state_next
2697 .format_trace = format_tcp_rx_trace_short,
2702 VLIB_REGISTER_NODE (tcp6_listen_node) =
2704 .name = "tcp6-listen",
2705 /* Takes a vector of packets. */
2706 .vector_size = sizeof (u32),
2707 .n_errors = TCP_N_ERROR,
2708 .error_strings = tcp_error_strings,
2709 .n_next_nodes = TCP_LISTEN_N_NEXT,
2712 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2713 foreach_tcp_state_next
2716 .format_trace = format_tcp_rx_trace_short,
2720 typedef enum _tcp_input_next
2722 TCP_INPUT_NEXT_DROP,
2723 TCP_INPUT_NEXT_LISTEN,
2724 TCP_INPUT_NEXT_RCV_PROCESS,
2725 TCP_INPUT_NEXT_SYN_SENT,
2726 TCP_INPUT_NEXT_ESTABLISHED,
2727 TCP_INPUT_NEXT_RESET,
2728 TCP_INPUT_NEXT_PUNT,
2732 #define foreach_tcp4_input_next \
2733 _ (DROP, "ip4-drop") \
2734 _ (LISTEN, "tcp4-listen") \
2735 _ (RCV_PROCESS, "tcp4-rcv-process") \
2736 _ (SYN_SENT, "tcp4-syn-sent") \
2737 _ (ESTABLISHED, "tcp4-established") \
2738 _ (RESET, "tcp4-reset") \
2739 _ (PUNT, "ip4-punt")
2741 #define foreach_tcp6_input_next \
2742 _ (DROP, "ip6-drop") \
2743 _ (LISTEN, "tcp6-listen") \
2744 _ (RCV_PROCESS, "tcp6-rcv-process") \
2745 _ (SYN_SENT, "tcp6-syn-sent") \
2746 _ (ESTABLISHED, "tcp6-established") \
2747 _ (RESET, "tcp6-reset") \
2748 _ (PUNT, "ip6-punt")
2750 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2753 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2754 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2756 tcp_connection_t *tc;
2761 for (i = 0; i < n_bufs; i++)
2763 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2765 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2766 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2768 tcp = vlib_buffer_get_current (bs[i]);
2769 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2775 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2777 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2779 *next = TCP_INPUT_NEXT_DROP;
2781 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2783 *next = TCP_INPUT_NEXT_PUNT;
2784 *error = TCP_ERROR_PUNT;
2788 *next = TCP_INPUT_NEXT_RESET;
2789 *error = TCP_ERROR_NO_LISTENER;
2794 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2795 vlib_buffer_t * b, u16 * next,
2796 vlib_node_runtime_t * error_node)
2802 tcp = tcp_buffer_hdr (b);
2803 flags = tcp->flags & filter_flags;
2804 *next = tm->dispatch_table[tc->state][flags].next;
2805 error = tm->dispatch_table[tc->state][flags].error;
2808 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2810 b->error = error_node->errors[error];
2811 if (error == TCP_ERROR_DISPATCH)
2812 clib_warning ("tcp conn %u disp error state %U flags %U",
2813 tc->c_c_index, format_tcp_state, tc->state,
2814 format_tcp_flags, (int) flags);
2819 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2820 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2822 u32 n_left_from, *from, thread_index = vm->thread_index;
2823 tcp_main_t *tm = vnet_get_tcp_main ();
2824 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2825 u16 nexts[VLIB_FRAME_SIZE], *next;
2827 tcp_set_time_now (tcp_get_worker (thread_index));
2829 from = vlib_frame_vector_args (frame);
2830 n_left_from = frame->n_vectors;
2831 vlib_get_buffers (vm, from, bufs, n_left_from);
2836 while (n_left_from >= 4)
2838 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2839 tcp_connection_t *tc0, *tc1;
2842 vlib_prefetch_buffer_header (b[2], STORE);
2843 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2845 vlib_prefetch_buffer_header (b[3], STORE);
2846 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2849 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2851 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2853 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2856 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2858 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2859 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2861 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2862 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2864 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2865 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2869 if (PREDICT_TRUE (tc0 != 0))
2871 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2872 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2873 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2877 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2878 b[0]->error = node->errors[error0];
2881 if (PREDICT_TRUE (tc1 != 0))
2883 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2884 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2885 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2889 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2890 b[1]->error = node->errors[error1];
2898 while (n_left_from > 0)
2900 tcp_connection_t *tc0;
2901 u32 error0 = TCP_ERROR_NO_LISTENER;
2903 if (n_left_from > 1)
2905 vlib_prefetch_buffer_header (b[1], STORE);
2906 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2909 next[0] = TCP_INPUT_NEXT_DROP;
2910 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2912 if (PREDICT_TRUE (tc0 != 0))
2914 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2915 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2916 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2920 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2921 b[0]->error = node->errors[error0];
2929 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2930 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2932 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2933 return frame->n_vectors;
2936 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2937 vlib_node_runtime_t * node,
2938 vlib_frame_t * from_frame)
2940 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2941 1 /* is_nolookup */ );
2944 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2945 vlib_node_runtime_t * node,
2946 vlib_frame_t * from_frame)
2948 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2949 1 /* is_nolookup */ );
2953 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2955 .name = "tcp4-input-nolookup",
2956 /* Takes a vector of packets. */
2957 .vector_size = sizeof (u32),
2958 .n_errors = TCP_N_ERROR,
2959 .error_strings = tcp_error_strings,
2960 .n_next_nodes = TCP_INPUT_N_NEXT,
2963 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2964 foreach_tcp4_input_next
2967 .format_buffer = format_tcp_header,
2968 .format_trace = format_tcp_rx_trace,
2973 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2975 .name = "tcp6-input-nolookup",
2976 /* Takes a vector of packets. */
2977 .vector_size = sizeof (u32),
2978 .n_errors = TCP_N_ERROR,
2979 .error_strings = tcp_error_strings,
2980 .n_next_nodes = TCP_INPUT_N_NEXT,
2983 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2984 foreach_tcp6_input_next
2987 .format_buffer = format_tcp_header,
2988 .format_trace = format_tcp_rx_trace,
2992 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2993 vlib_frame_t * from_frame)
2995 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2996 0 /* is_nolookup */ );
2999 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3000 vlib_frame_t * from_frame)
3002 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3003 0 /* is_nolookup */ );
3007 VLIB_REGISTER_NODE (tcp4_input_node) =
3009 .name = "tcp4-input",
3010 /* Takes a vector of packets. */
3011 .vector_size = sizeof (u32),
3012 .n_errors = TCP_N_ERROR,
3013 .error_strings = tcp_error_strings,
3014 .n_next_nodes = TCP_INPUT_N_NEXT,
3017 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3018 foreach_tcp4_input_next
3021 .format_buffer = format_tcp_header,
3022 .format_trace = format_tcp_rx_trace,
3027 VLIB_REGISTER_NODE (tcp6_input_node) =
3029 .name = "tcp6-input",
3030 /* Takes a vector of packets. */
3031 .vector_size = sizeof (u32),
3032 .n_errors = TCP_N_ERROR,
3033 .error_strings = tcp_error_strings,
3034 .n_next_nodes = TCP_INPUT_N_NEXT,
3037 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3038 foreach_tcp6_input_next
3041 .format_buffer = format_tcp_header,
3042 .format_trace = format_tcp_rx_trace,
3046 #ifndef CLIB_MARCH_VARIANT
3048 tcp_dispatch_table_init (tcp_main_t * tm)
3051 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3052 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3054 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3055 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3058 #define _(t,f,n,e) \
3060 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3061 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3064 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3065 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3066 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3067 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3068 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3069 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3070 TCP_ERROR_ACK_INVALID);
3071 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3072 TCP_ERROR_SEGMENT_INVALID);
3073 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3074 TCP_ERROR_SEGMENT_INVALID);
3075 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3076 TCP_ERROR_INVALID_CONNECTION);
3077 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3078 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3079 TCP_ERROR_SEGMENT_INVALID);
3080 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3081 TCP_ERROR_SEGMENT_INVALID);
3082 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3083 TCP_ERROR_SEGMENT_INVALID);
3084 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3085 TCP_ERROR_SEGMENT_INVALID);
3086 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3087 TCP_ERROR_SEGMENT_INVALID);
3088 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3089 TCP_ERROR_SEGMENT_INVALID);
3090 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3091 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3092 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3093 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3094 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3095 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3097 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3098 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3100 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3102 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3103 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3104 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3105 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3107 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3109 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3110 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3111 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3113 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3114 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3115 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3116 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3117 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3118 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3119 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3120 /* SYN-ACK for a SYN */
3121 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3123 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3124 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3125 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3127 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3128 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3130 /* ACK for for established connection -> tcp-established. */
3131 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3132 /* FIN for for established connection -> tcp-established. */
3133 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3134 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3136 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3138 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3139 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3140 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3142 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3143 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3144 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3145 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3146 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3147 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3148 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3149 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3151 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3152 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3154 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3156 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3157 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3158 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3159 /* ACK or FIN-ACK to our FIN */
3160 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3161 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3163 /* FIN in reply to our FIN from the other side */
3164 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3165 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3166 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3168 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3169 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3170 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3171 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3172 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3173 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3174 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3176 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3177 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3178 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3179 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3181 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3183 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3184 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3185 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3186 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3188 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3189 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3190 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3191 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3193 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3195 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3196 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3197 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3198 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3200 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3201 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3203 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3205 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3206 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3207 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3209 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3210 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3211 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3212 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3213 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3214 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3215 /* FIN confirming that the peer (app) has closed */
3216 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3217 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3218 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3220 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3221 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3223 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3224 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3227 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3230 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3231 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3232 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3233 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3236 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3238 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3239 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3240 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3242 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3243 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3244 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3245 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3246 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3247 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3248 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3249 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3251 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3252 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3254 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3256 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3257 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3258 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3259 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3260 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3262 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3263 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3265 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3266 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3267 * incoming segment not containing a RST causes a RST to be sent in
3269 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3270 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3271 TCP_ERROR_CONNECTION_CLOSED);
3272 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3273 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3274 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3275 TCP_ERROR_CONNECTION_CLOSED);
3279 static clib_error_t *
3280 tcp_input_init (vlib_main_t * vm)
3282 clib_error_t *error = 0;
3283 tcp_main_t *tm = vnet_get_tcp_main ();
3285 if ((error = vlib_call_init_function (vm, tcp_init)))
3288 /* Initialize dispatch table. */
3289 tcp_dispatch_table_init (tm);
3294 VLIB_INIT_FUNCTION (tcp_input_init);
3296 #endif /* CLIB_MARCH_VARIANT */
3299 * fd.io coding-style-patch-verification: ON
3302 * eval: (c-set-style "gnu")