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 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_una_max - tc->snd_una);
585 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
587 if (seq_leq (tc->psh_seq, tc->snd_una))
588 tc->flags &= ~TCP_CONN_PSH_PENDING;
591 if (tcp_is_descheduled (tc))
594 /* If everything has been acked, stop retransmit timer
595 * otherwise update. */
596 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
598 /* Update pacer based on our new cwnd estimate */
599 tcp_connection_tx_pacer_update (tc);
603 _vec_len (wrk->pending_deq_acked) = 0;
607 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
609 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
611 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
612 tc->flags |= TCP_CONN_DEQ_PENDING;
614 tc->burst_acked += tc->bytes_acked;
618 * Try to update snd_wnd based on feedback received from peer.
620 * If successful, and new window is 'effectively' 0, activate persist
624 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
626 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
627 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
628 if (seq_lt (tc->snd_wl1, seq)
629 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
631 tc->snd_wnd = snd_wnd;
634 TCP_EVT (TCP_EVT_SND_WND, tc);
636 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
638 /* Set persist timer if not set and we just got 0 wnd */
639 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
640 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
642 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
643 tcp_persist_timer_set (&wrk->timer_wheel, tc);
648 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
650 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
651 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
654 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
657 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
667 * Init loss recovery/fast recovery.
669 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
670 * updated in @ref tcp_cc_handle_event after fast retransmit
673 tcp_cc_init_congestion (tcp_connection_t * tc)
675 tcp_fastrecovery_on (tc);
676 tc->snd_congestion = tc->snd_nxt;
677 tc->cwnd_acc_bytes = 0;
678 tc->snd_rxt_bytes = 0;
679 tc->rxt_delivered = 0;
680 tc->prr_delivered = 0;
681 tc->prr_start = tc->snd_una;
682 tc->prev_ssthresh = tc->ssthresh;
683 tc->prev_cwnd = tc->cwnd;
685 tc->snd_rxt_ts = tcp_tstamp (tc);
686 tcp_cc_congestion (tc);
688 /* Post retransmit update cwnd to ssthresh and account for the
689 * three segments that have left the network and should've been
690 * buffered at the receiver XXX */
691 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
692 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
694 tc->fr_occurences += 1;
695 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
699 tcp_cc_congestion_undo (tcp_connection_t * tc)
701 tc->cwnd = tc->prev_cwnd;
702 tc->ssthresh = tc->prev_ssthresh;
703 tcp_cc_undo_recovery (tc);
704 ASSERT (tc->rto_boff == 0);
705 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
709 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
711 return (tcp_in_recovery (tc) && tc->rto_boff == 1
713 && tcp_opts_tstamp (&tc->rcv_opts)
714 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
718 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
720 return (tcp_cc_is_spurious_timeout_rxt (tc));
724 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
728 /* If of of the two conditions lower hold, reset dupacks because
729 * we're probably after timeout (RFC6582 heuristics).
730 * If Cumulative ack does not cover more than congestion threshold,
732 * 1) The following doesn't hold: The congestion window is greater
733 * than SMSS bytes and the difference between highest_ack
734 * and prev_highest_ack is at most 4*SMSS bytes
735 * 2) Echoed timestamp in the last non-dup ack does not equal the
738 if (seq_leq (tc->snd_una, tc->snd_congestion)
739 && ((!(tc->cwnd > tc->snd_mss
740 && tc->bytes_acked <= 4 * tc->snd_mss))
741 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
747 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
751 tcp_cc_recover (tcp_connection_t * tc)
753 sack_scoreboard_hole_t *hole;
756 ASSERT (tcp_in_cong_recovery (tc));
758 if (tcp_cc_is_spurious_retransmit (tc))
760 tcp_cc_congestion_undo (tc);
764 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
767 /* Previous recovery left us congested. Continue sending as part
768 * of the current recovery event with an updated snd_congestion */
769 if (tc->sack_sb.sacked_bytes)
771 tc->snd_congestion = tc->snd_nxt;
772 tcp_program_retransmit (tc);
776 tc->rxt_delivered = 0;
777 tc->snd_rxt_bytes = 0;
779 tc->prr_delivered = 0;
781 tc->flags &= ~TCP_CONN_RXT_PENDING;
783 hole = scoreboard_first_hole (&tc->sack_sb);
784 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
785 scoreboard_clear (&tc->sack_sb);
787 if (!tcp_in_recovery (tc) && !is_spurious)
788 tcp_cc_recovered (tc);
790 tcp_fastrecovery_off (tc);
791 tcp_fastrecovery_first_off (tc);
792 tcp_recovery_off (tc);
793 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
795 ASSERT (tc->rto_boff == 0);
796 ASSERT (!tcp_in_cong_recovery (tc));
797 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
803 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
805 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
807 /* Congestion avoidance */
808 tcp_cc_rcv_ack (tc, rs);
810 /* If a cumulative ack, make sure dupacks is 0 */
813 /* When dupacks hits the threshold we only enter fast retransmit if
814 * cumulative ack covers more than snd_congestion. Should snd_una
815 * wrap this test may fail under otherwise valid circumstances.
816 * Therefore, proactively update snd_congestion when wrap detected. */
818 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
819 && seq_gt (tc->snd_congestion, tc->snd_una)))
820 tc->snd_congestion = tc->snd_una - 1;
824 * One function to rule them all ... and in the darkness bind them
827 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
830 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
832 /* If reneging, wait for timer based retransmits */
833 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
837 * If not in recovery, figure out if we should enter
839 if (!tcp_in_cong_recovery (tc))
844 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
845 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
847 if (tcp_should_fastrecover (tc, has_sack))
849 tcp_cc_init_congestion (tc);
852 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
854 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
855 tcp_program_retransmit (tc);
862 * Already in recovery
866 * Process (re)transmit feedback. Output path uses this to decide how much
867 * more data to release into the network
871 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
872 tcp_fastrecovery_first_on (tc);
874 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
875 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
876 - tc->sack_sb.last_bytes_delivered;
882 tc->rcv_dupacks += 1;
883 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
885 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
888 tc->prr_delivered += clib_min (tc->snd_mss,
889 tc->snd_nxt - tc->snd_una);
891 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
895 /* If partial ack, assume that the first un-acked segment was lost */
896 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
897 tcp_fastrecovery_first_on (tc);
901 * See if we can exit and stop retransmitting
903 if (seq_geq (tc->snd_una, tc->snd_congestion))
905 /* If spurious return, we've already updated everything */
906 if (tcp_cc_recover (tc))
908 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
912 /* Treat as congestion avoidance ack */
913 tcp_cc_rcv_ack (tc, rs);
917 tcp_program_retransmit (tc);
920 * Notify cc of the event
923 if (!tc->bytes_acked)
925 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
929 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
930 * reset dupacks to 0. Also needed if in congestion recovery */
933 if (tcp_in_recovery (tc))
934 tcp_cc_rcv_ack (tc, rs);
936 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
940 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
942 if (!tcp_in_cong_recovery (tc))
945 if (tcp_opts_sack_permitted (&tc->rcv_opts))
946 tcp_rcv_sacks (tc, tc->snd_una);
950 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
951 tcp_bt_sample_delivery_rate (tc, rs);
953 tcp_cc_handle_event (tc, rs, 1);
957 * Check if duplicate ack as per RFC5681 Sec. 2
960 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
963 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
964 && seq_gt (tc->snd_nxt, tc->snd_una)
965 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
966 && (prev_snd_wnd == tc->snd_wnd));
970 * Checks if ack is a congestion control event.
973 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
974 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
976 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
977 * defined to be 'duplicate' as well */
978 *is_dack = tc->sack_sb.last_sacked_bytes
979 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
981 return (*is_dack || tcp_in_cong_recovery (tc));
985 * Process incoming ACK
988 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
989 tcp_header_t * th, u32 * error)
991 u32 prev_snd_wnd, prev_snd_una;
992 tcp_rate_sample_t rs = { 0 };
995 TCP_EVT (TCP_EVT_CC_STAT, tc);
997 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
998 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1000 /* We've probably entered recovery and the peer still has some
1001 * of the data we've sent. Update snd_nxt and accept the ack */
1002 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1003 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1005 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1009 tc->errors.above_ack_wnd += 1;
1010 *error = TCP_ERROR_ACK_FUTURE;
1011 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1015 /* If old ACK, probably it's an old dupack */
1016 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1018 tc->errors.below_ack_wnd += 1;
1019 *error = TCP_ERROR_ACK_OLD;
1020 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1022 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1025 tcp_handle_old_ack (tc, &rs);
1027 /* Don't drop yet */
1034 * Looks okay, process feedback
1037 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1038 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1040 prev_snd_wnd = tc->snd_wnd;
1041 prev_snd_una = tc->snd_una;
1042 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1043 vnet_buffer (b)->tcp.ack_number,
1044 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1045 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1046 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1047 tcp_validate_txf_size (tc, tc->bytes_acked);
1049 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1050 tcp_bt_sample_delivery_rate (tc, &rs);
1052 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1054 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1055 if (tc->bytes_acked)
1056 tcp_program_dequeue (wrk, tc);
1059 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1062 * Check if we have congestion event
1065 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1067 tcp_cc_handle_event (tc, &rs, is_dack);
1068 tc->dupacks_in += is_dack;
1069 if (!tcp_in_cong_recovery (tc))
1071 *error = TCP_ERROR_ACK_OK;
1074 *error = TCP_ERROR_ACK_DUP;
1075 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1081 * Update congestion control (slow start/congestion avoidance)
1083 tcp_cc_update (tc, &rs);
1084 *error = TCP_ERROR_ACK_OK;
1089 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1091 if (!tcp_disconnect_pending (tc))
1093 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1094 tcp_disconnect_pending_on (tc);
1099 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1101 u32 thread_index, *pending_disconnects, *pending_resets;
1102 tcp_connection_t *tc;
1105 if (vec_len (wrk->pending_disconnects))
1107 thread_index = wrk->vm->thread_index;
1108 pending_disconnects = wrk->pending_disconnects;
1109 for (i = 0; i < vec_len (pending_disconnects); i++)
1111 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1112 tcp_disconnect_pending_off (tc);
1113 session_transport_closing_notify (&tc->connection);
1115 _vec_len (wrk->pending_disconnects) = 0;
1118 if (vec_len (wrk->pending_resets))
1120 thread_index = wrk->vm->thread_index;
1121 pending_resets = wrk->pending_resets;
1122 for (i = 0; i < vec_len (pending_resets); i++)
1124 tc = tcp_connection_get (pending_resets[i], thread_index);
1125 tcp_disconnect_pending_off (tc);
1126 tcp_handle_rst (tc);
1128 _vec_len (wrk->pending_resets) = 0;
1133 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1136 /* Reject out-of-order fins */
1137 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1140 /* Account for the FIN and send ack */
1142 tc->flags |= TCP_CONN_FINRCVD;
1143 tcp_program_ack (tc);
1144 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1145 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1146 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1147 tcp_program_disconnect (wrk, tc);
1148 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1149 tcp_cfg.closewait_time);
1150 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1151 *error = TCP_ERROR_FIN_RCVD;
1154 /** Enqueue data for delivery to application */
1156 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1159 int written, error = TCP_ERROR_ENQUEUED;
1161 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1163 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1164 1 /* queue event */ , 1);
1165 tc->bytes_in += written;
1167 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1169 /* Update rcv_nxt */
1170 if (PREDICT_TRUE (written == data_len))
1172 tc->rcv_nxt += written;
1174 /* If more data written than expected, account for out-of-order bytes. */
1175 else if (written > data_len)
1177 tc->rcv_nxt += written;
1178 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1180 else if (written > 0)
1182 /* We've written something but FIFO is probably full now */
1183 tc->rcv_nxt += written;
1184 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1188 /* Packet made it through for ack processing */
1189 if (tc->rcv_wnd < tc->snd_mss)
1190 return TCP_ERROR_ZERO_RWND;
1192 return TCP_ERROR_FIFO_FULL;
1195 /* Update SACK list if need be */
1196 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1198 /* Remove SACK blocks that have been delivered */
1199 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1205 /** Enqueue out-of-order data */
1207 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1213 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1216 /* Enqueue out-of-order data with relative offset */
1217 rv = session_enqueue_stream_connection (&tc->connection, b,
1218 vnet_buffer (b)->tcp.seq_number -
1219 tc->rcv_nxt, 0 /* queue event */ ,
1222 /* Nothing written */
1225 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1226 return TCP_ERROR_FIFO_FULL;
1229 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1230 tc->bytes_in += data_len;
1232 /* Update SACK list if in use */
1233 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1235 ooo_segment_t *newest;
1238 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1240 /* Get the newest segment from the fifo */
1241 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1244 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1245 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1246 start = tc->rcv_nxt + offset;
1247 end = start + ooo_segment_length (s0->rx_fifo, newest);
1248 tcp_update_sack_list (tc, start, end);
1249 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1250 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1254 return TCP_ERROR_ENQUEUED_OOO;
1258 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1260 u32 discard, first = b->current_length;
1261 vlib_main_t *vm = vlib_get_main ();
1263 /* Handle multi-buffer segments */
1264 if (n_bytes_to_drop > b->current_length)
1266 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1270 discard = clib_min (n_bytes_to_drop, b->current_length);
1271 vlib_buffer_advance (b, discard);
1272 b = vlib_get_buffer (vm, b->next_buffer);
1273 n_bytes_to_drop -= discard;
1275 while (n_bytes_to_drop);
1276 if (n_bytes_to_drop > first)
1277 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1280 vlib_buffer_advance (b, n_bytes_to_drop);
1281 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1286 * Receive buffer for connection and handle acks
1288 * It handles both in order or out-of-order data.
1291 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1294 u32 error, n_bytes_to_drop, n_data_bytes;
1296 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1297 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1298 ASSERT (n_data_bytes);
1299 tc->data_segs_in += 1;
1301 /* Handle out-of-order data */
1302 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1304 /* Old sequence numbers allowed through because they overlapped
1306 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1308 /* Completely in the past (possible retransmit). Ack
1309 * retransmissions since we may not have any data to send */
1310 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1312 tcp_program_dupack (tc);
1313 tc->errors.below_data_wnd++;
1314 error = TCP_ERROR_SEGMENT_OLD;
1318 /* Chop off the bytes in the past and see if what is left
1319 * can be enqueued in order */
1320 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1321 n_data_bytes -= n_bytes_to_drop;
1322 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1323 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1325 error = TCP_ERROR_SEGMENT_OLD;
1331 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1332 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1333 tcp_program_dupack (tc);
1334 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1335 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1336 tc->rcv_las + tc->rcv_wnd);
1342 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1343 * segments can be enqueued after fifo tail offset changes. */
1344 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1345 tcp_program_ack (tc);
1353 tcp_header_t tcp_header;
1354 tcp_connection_t tcp_connection;
1358 format_tcp_rx_trace (u8 * s, va_list * args)
1360 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1361 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1362 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1363 tcp_connection_t *tc = &t->tcp_connection;
1364 u32 indent = format_get_indent (s);
1366 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1367 format_tcp_state, tc->state, format_white_space, indent,
1368 format_tcp_header, &t->tcp_header, 128);
1374 format_tcp_rx_trace_short (u8 * s, va_list * args)
1376 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1377 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1378 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1380 s = format (s, "%d -> %d (%U)",
1381 clib_net_to_host_u16 (t->tcp_header.dst_port),
1382 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1383 t->tcp_connection.state);
1389 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1390 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1394 clib_memcpy_fast (&t0->tcp_connection, tc0,
1395 sizeof (t0->tcp_connection));
1399 th0 = tcp_buffer_hdr (b0);
1401 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1405 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1406 vlib_frame_t * frame, u8 is_ip4)
1410 n_left = frame->n_vectors;
1411 from = vlib_frame_vector_args (frame);
1415 tcp_connection_t *tc0;
1422 b0 = vlib_get_buffer (vm, bi0);
1424 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1426 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1427 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1429 th0 = tcp_buffer_hdr (b0);
1430 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1439 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1440 u8 is_ip4, u32 evt, u32 val)
1443 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1445 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1448 #define tcp_maybe_inc_counter(node_id, err, count) \
1450 if (next0 != tcp_next_drop (is_ip4)) \
1451 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1452 tcp6_##node_id##_node.index, is_ip4, err, \
1455 #define tcp_inc_counter(node_id, err, count) \
1456 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1457 tcp6_##node_id##_node.index, is_ip4, \
1459 #define tcp_maybe_inc_err_counter(cnts, err) \
1461 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1463 #define tcp_inc_err_counter(cnts, err, val) \
1467 #define tcp_store_err_counters(node_id, cnts) \
1470 for (i = 0; i < TCP_N_ERROR; i++) \
1472 tcp_inc_counter(node_id, i, cnts[i]); \
1477 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1478 vlib_frame_t * frame, int is_ip4)
1480 u32 thread_index = vm->thread_index, errors = 0;
1481 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1482 u32 n_left_from, *from, *first_buffer;
1483 u16 err_counters[TCP_N_ERROR] = { 0 };
1485 if (node->flags & VLIB_NODE_FLAG_TRACE)
1486 tcp_established_trace_frame (vm, node, frame, is_ip4);
1488 first_buffer = from = vlib_frame_vector_args (frame);
1489 n_left_from = frame->n_vectors;
1491 while (n_left_from > 0)
1493 u32 bi0, error0 = TCP_ERROR_ACK_OK;
1496 tcp_connection_t *tc0;
1498 if (n_left_from > 1)
1501 pb = vlib_get_buffer (vm, from[1]);
1502 vlib_prefetch_buffer_header (pb, LOAD);
1503 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1510 b0 = vlib_get_buffer (vm, bi0);
1511 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1514 if (PREDICT_FALSE (tc0 == 0))
1516 error0 = TCP_ERROR_INVALID_CONNECTION;
1520 th0 = tcp_buffer_hdr (b0);
1522 /* TODO header prediction fast path */
1524 /* 1-4: check SEQ, RST, SYN */
1525 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
1527 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
1531 /* 5: check the ACK field */
1532 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
1535 /* 6: check the URG bit TODO */
1537 /* 7: process the segment text */
1538 if (vnet_buffer (b0)->tcp.data_len)
1539 error0 = tcp_segment_rcv (wrk, tc0, b0);
1541 /* 8: check the FIN bit */
1542 if (PREDICT_FALSE (tcp_is_fin (th0)))
1543 tcp_rcv_fin (wrk, tc0, b0, &error0);
1546 tcp_inc_err_counter (err_counters, error0, 1);
1549 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1551 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1552 tcp_store_err_counters (established, err_counters);
1553 tcp_handle_postponed_dequeues (wrk);
1554 tcp_handle_disconnects (wrk);
1555 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
1557 return frame->n_vectors;
1560 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1561 vlib_node_runtime_t * node,
1562 vlib_frame_t * from_frame)
1564 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1567 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1568 vlib_node_runtime_t * node,
1569 vlib_frame_t * from_frame)
1571 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1575 VLIB_REGISTER_NODE (tcp4_established_node) =
1577 .name = "tcp4-established",
1578 /* Takes a vector of packets. */
1579 .vector_size = sizeof (u32),
1580 .n_errors = TCP_N_ERROR,
1581 .error_strings = tcp_error_strings,
1582 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1585 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1586 foreach_tcp_state_next
1589 .format_trace = format_tcp_rx_trace_short,
1594 VLIB_REGISTER_NODE (tcp6_established_node) =
1596 .name = "tcp6-established",
1597 /* Takes a vector of packets. */
1598 .vector_size = sizeof (u32),
1599 .n_errors = TCP_N_ERROR,
1600 .error_strings = tcp_error_strings,
1601 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1604 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1605 foreach_tcp_state_next
1608 .format_trace = format_tcp_rx_trace_short,
1614 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1617 transport_connection_t *tmp = 0;
1624 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1627 u8 is_ip_valid = 0, val_l, val_r;
1629 if (tc->connection.is_ip4)
1631 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1633 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1634 &tc->connection.lcl_ip.ip4);
1635 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1636 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1637 &tc->connection.rmt_ip.ip4);
1638 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1639 is_ip_valid = val_l && val_r;
1643 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1645 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1646 &tc->connection.lcl_ip.ip6);
1647 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1648 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1649 &tc->connection.rmt_ip.ip6);
1650 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1651 is_ip_valid = val_l && val_r;
1654 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1655 && (tc->state == TCP_STATE_LISTEN
1656 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1660 handle = session_lookup_half_open_handle (&tc->connection);
1661 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1662 tc->c_proto, tc->c_is_ip4);
1666 if (tmp->lcl_port == hdr->dst_port
1667 && tmp->rmt_port == hdr->src_port)
1669 TCP_DBG ("half-open is valid!");
1678 * Lookup transport connection
1680 static tcp_connection_t *
1681 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1685 transport_connection_t *tconn;
1686 tcp_connection_t *tc;
1691 ip4 = vlib_buffer_get_current (b);
1692 tcp = ip4_next_header (ip4);
1693 tconn = session_lookup_connection_wt4 (fib_index,
1698 TRANSPORT_PROTO_TCP,
1699 thread_index, &is_filtered);
1700 tc = tcp_get_connection_from_transport (tconn);
1701 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1706 ip6 = vlib_buffer_get_current (b);
1707 tcp = ip6_next_header (ip6);
1708 tconn = session_lookup_connection_wt6 (fib_index,
1713 TRANSPORT_PROTO_TCP,
1714 thread_index, &is_filtered);
1715 tc = tcp_get_connection_from_transport (tconn);
1716 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1721 static tcp_connection_t *
1722 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1728 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1729 tcp_header_t *tcp = tcp_buffer_hdr (b);
1730 s = session_lookup_listener4 (fib_index,
1732 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1736 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1737 tcp_header_t *tcp = tcp_buffer_hdr (b);
1738 s = session_lookup_listener6 (fib_index,
1740 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1743 if (PREDICT_TRUE (s != 0))
1744 return tcp_get_connection_from_transport (transport_get_listener
1745 (TRANSPORT_PROTO_TCP,
1746 s->connection_index));
1752 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1754 vnet_main_t *vnm = vnet_get_main ();
1755 const dpo_id_t *dpo;
1756 const load_balance_t *lb;
1757 vnet_hw_interface_t *hw_if;
1758 u32 sw_if_idx, lb_idx;
1762 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1763 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1767 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1768 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1771 lb = load_balance_get (lb_idx);
1772 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1774 dpo = load_balance_get_bucket_i (lb, 0);
1776 sw_if_idx = dpo_get_urpf (dpo);
1777 if (PREDICT_FALSE (sw_if_idx == ~0))
1780 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1781 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
1782 tc->cfg_flags |= TCP_CFG_F_TSO;
1786 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1787 vlib_frame_t * from_frame, int is_ip4)
1789 u32 n_left_from, *from, *first_buffer, errors = 0;
1790 u32 my_thread_index = vm->thread_index;
1791 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
1793 from = first_buffer = vlib_frame_vector_args (from_frame);
1794 n_left_from = from_frame->n_vectors;
1796 while (n_left_from > 0)
1798 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
1799 tcp_connection_t *tc0, *new_tc0;
1800 tcp_header_t *tcp0 = 0;
1808 b0 = vlib_get_buffer (vm, bi0);
1810 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
1811 if (PREDICT_FALSE (tc0 == 0))
1813 error0 = TCP_ERROR_INVALID_CONNECTION;
1817 /* Half-open completed recently but the connection was't removed
1818 * yet by the owning thread */
1819 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1821 /* Make sure the connection actually exists */
1822 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
1823 my_thread_index, is_ip4));
1824 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
1828 ack0 = vnet_buffer (b0)->tcp.ack_number;
1829 seq0 = vnet_buffer (b0)->tcp.seq_number;
1830 tcp0 = tcp_buffer_hdr (b0);
1832 /* Crude check to see if the connection handle does not match
1833 * the packet. Probably connection just switched to established */
1834 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1835 || tcp0->src_port != tc0->c_rmt_port))
1837 error0 = TCP_ERROR_INVALID_CONNECTION;
1841 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
1842 && !tcp_syn (tcp0)))
1844 error0 = TCP_ERROR_SEGMENT_INVALID;
1848 /* SYNs consume sequence numbers */
1849 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
1852 * 1. check the ACK bit
1856 * If the ACK bit is set
1857 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1858 * the RST bit is set, if so drop the segment and return)
1859 * <SEQ=SEG.ACK><CTL=RST>
1860 * and discard the segment. Return.
1861 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1865 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
1867 if (!tcp_rst (tcp0))
1868 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1869 error0 = TCP_ERROR_RCV_WND;
1873 /* Make sure ACK is valid */
1874 if (seq_gt (tc0->snd_una, ack0))
1876 error0 = TCP_ERROR_ACK_INVALID;
1882 * 2. check the RST bit
1887 /* If ACK is acceptable, signal client that peer is not
1888 * willing to accept connection and drop connection*/
1890 tcp_rcv_rst (wrk, tc0);
1891 error0 = TCP_ERROR_RST_RCVD;
1896 * 3. check the security and precedence (skipped)
1900 * 4. check the SYN bit
1903 /* No SYN flag. Drop. */
1904 if (!tcp_syn (tcp0))
1906 error0 = TCP_ERROR_SEGMENT_INVALID;
1911 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
1913 error0 = TCP_ERROR_OPTIONS;
1917 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1918 * current thread pool. */
1919 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
1920 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
1921 new_tc0->irs = seq0;
1922 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1923 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1925 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
1927 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
1928 new_tc0->tsval_recent_age = tcp_time_now ();
1931 if (tcp_opts_wscale (&new_tc0->rcv_opts))
1932 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
1934 new_tc0->rcv_wscale = 0;
1936 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
1937 << new_tc0->snd_wscale;
1938 new_tc0->snd_wl1 = seq0;
1939 new_tc0->snd_wl2 = ack0;
1941 tcp_connection_init_vars (new_tc0);
1943 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1944 if (PREDICT_TRUE (tcp_ack (tcp0)))
1946 /* Our SYN is ACKed: we have iss < ack = snd_una */
1948 /* TODO Dequeue acknowledged segments if we support Fast Open */
1949 new_tc0->snd_una = ack0;
1950 new_tc0->state = TCP_STATE_ESTABLISHED;
1952 /* Make sure las is initialized for the wnd computation */
1953 new_tc0->rcv_las = new_tc0->rcv_nxt;
1955 /* Notify app that we have connection. If session layer can't
1956 * allocate session send reset */
1957 if (session_stream_connect_notify (&new_tc0->connection,
1960 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
1961 tcp_connection_cleanup (new_tc0);
1962 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
1966 new_tc0->tx_fifo_size =
1967 transport_tx_fifo_size (&new_tc0->connection);
1968 /* Update rtt with the syn-ack sample */
1969 tcp_estimate_initial_rtt (new_tc0);
1970 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
1971 error0 = TCP_ERROR_SYN_ACKS_RCVD;
1973 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1976 new_tc0->state = TCP_STATE_SYN_RCVD;
1978 /* Notify app that we have connection */
1979 if (session_stream_connect_notify (&new_tc0->connection,
1982 tcp_connection_cleanup (new_tc0);
1983 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
1984 TCP_EVT (TCP_EVT_RST_SENT, tc0);
1985 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
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);
2384 case TCP_STATE_CLOSE_WAIT:
2385 case TCP_STATE_CLOSING:
2386 case TCP_STATE_LAST_ACK:
2387 case TCP_STATE_TIME_WAIT:
2388 /* This should not occur, since a FIN has been received from the
2389 * remote side. Ignore the segment text. */
2393 /* 8: check the FIN bit */
2397 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
2401 case TCP_STATE_ESTABLISHED:
2402 /* Account for the FIN and send ack */
2404 tcp_program_ack (tc0);
2405 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
2406 tcp_program_disconnect (wrk, tc0);
2407 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2408 tcp_cfg.closewait_time);
2410 case TCP_STATE_SYN_RCVD:
2411 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2412 * notified yet, set a cleanup timer instead of relying on
2413 * disconnect notify and the implicit close call. */
2414 tcp_connection_timers_reset (tc0);
2417 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2418 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2419 tcp_cfg.lastack_time);
2421 case TCP_STATE_CLOSE_WAIT:
2422 case TCP_STATE_CLOSING:
2423 case TCP_STATE_LAST_ACK:
2426 case TCP_STATE_FIN_WAIT_1:
2429 if (tc0->flags & TCP_CONN_FINPNDG)
2431 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2432 * sending it. Since we already received a fin, do not wait
2434 tc0->flags |= TCP_CONN_FINRCVD;
2435 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2436 tcp_cfg.closewait_time);
2440 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2441 tcp_program_ack (tc0);
2442 /* Wait for ACK for our FIN but not forever */
2443 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2444 tcp_cfg.closing_time);
2447 case TCP_STATE_FIN_WAIT_2:
2448 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2450 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2451 tcp_connection_timers_reset (tc0);
2452 tcp_timer_set (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2453 tcp_cfg.timewait_time);
2454 tcp_program_ack (tc0);
2455 session_transport_closed_notify (&tc0->connection);
2457 case TCP_STATE_TIME_WAIT:
2458 /* Remain in the TIME-WAIT state. Restart the time-wait
2461 tcp_timer_update (&wrk->timer_wheel, tc0, TCP_TIMER_WAITCLOSE,
2462 tcp_cfg.timewait_time);
2465 error0 = TCP_ERROR_FIN_RCVD;
2469 tcp_inc_counter (rcv_process, error0, 1);
2470 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2472 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2473 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2477 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2479 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2480 tcp_handle_postponed_dequeues (wrk);
2481 tcp_handle_disconnects (wrk);
2482 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2484 return from_frame->n_vectors;
2487 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2488 vlib_node_runtime_t * node,
2489 vlib_frame_t * from_frame)
2491 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2494 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2495 vlib_node_runtime_t * node,
2496 vlib_frame_t * from_frame)
2498 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2502 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2504 .name = "tcp4-rcv-process",
2505 /* Takes a vector of packets. */
2506 .vector_size = sizeof (u32),
2507 .n_errors = TCP_N_ERROR,
2508 .error_strings = tcp_error_strings,
2509 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2512 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2513 foreach_tcp_state_next
2516 .format_trace = format_tcp_rx_trace_short,
2521 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2523 .name = "tcp6-rcv-process",
2524 /* Takes a vector of packets. */
2525 .vector_size = sizeof (u32),
2526 .n_errors = TCP_N_ERROR,
2527 .error_strings = tcp_error_strings,
2528 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2531 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2532 foreach_tcp_state_next
2535 .format_trace = format_tcp_rx_trace_short,
2540 * LISTEN state processing as per RFC 793 p. 65
2543 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2544 vlib_frame_t * from_frame, int is_ip4)
2546 u32 n_left_from, *from, n_syns = 0, *first_buffer;
2547 u32 thread_index = vm->thread_index;
2549 from = first_buffer = vlib_frame_vector_args (from_frame);
2550 n_left_from = from_frame->n_vectors;
2552 while (n_left_from > 0)
2554 u32 bi, error = TCP_ERROR_NONE;
2555 tcp_connection_t *lc, *child;
2562 b = vlib_get_buffer (vm, bi);
2564 lc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2565 if (PREDICT_FALSE (lc == 0))
2567 tcp_connection_t *tc;
2568 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2570 if (tc->state != TCP_STATE_TIME_WAIT)
2572 error = TCP_ERROR_CREATE_EXISTS;
2575 lc = tcp_lookup_listener (b, tc->c_fib_index, is_ip4);
2576 /* clean up the old session */
2577 tcp_connection_del (tc);
2580 /* Make sure connection wasn't just created */
2581 child = tcp_lookup_connection (lc->c_fib_index, b, thread_index,
2583 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2585 error = TCP_ERROR_CREATE_EXISTS;
2589 /* Create child session. For syn-flood protection use filter */
2591 /* 1. first check for an RST: handled in dispatch */
2592 /* if (tcp_rst (th0))
2596 /* 2. second check for an ACK: handled in dispatch */
2597 /* if (tcp_ack (th0))
2599 tcp_send_reset (b0, is_ip4);
2604 /* 3. check for a SYN (did that already) */
2606 /* Create child session and send SYN-ACK */
2607 child = tcp_connection_alloc (thread_index);
2609 if (tcp_options_parse (tcp_buffer_hdr (b), &child->rcv_opts, 1))
2611 error = TCP_ERROR_OPTIONS;
2612 tcp_connection_free (child);
2616 tcp_init_w_buffer (child, b, is_ip4);
2618 child->state = TCP_STATE_SYN_RCVD;
2619 child->c_fib_index = lc->c_fib_index;
2620 child->cc_algo = lc->cc_algo;
2621 tcp_connection_init_vars (child);
2622 child->rto = TCP_RTO_MIN;
2625 * This initializes elog track, must be done before synack.
2626 * We also do it before possible tcp_connection_cleanup() as it
2627 * generates TCP_EVT_DELETE event.
2629 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2631 if (session_stream_accept (&child->connection, lc->c_s_index,
2632 lc->c_thread_index, 0 /* notify */ ))
2634 tcp_connection_cleanup (child);
2635 error = TCP_ERROR_CREATE_SESSION_FAIL;
2639 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2641 tcp_send_synack (child);
2645 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
2648 t = vlib_add_trace (vm, node, b, sizeof (*t));
2649 clib_memcpy_fast (&t->tcp_header, tcp_buffer_hdr (b),
2650 sizeof (t->tcp_header));
2651 clib_memcpy_fast (&t->tcp_connection, lc,
2652 sizeof (t->tcp_connection));
2655 n_syns += (error == TCP_ERROR_NONE);
2658 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2659 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2661 return from_frame->n_vectors;
2664 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2665 vlib_frame_t * from_frame)
2667 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2670 VLIB_NODE_FN (tcp6_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, 0 /* is_ip4 */ );
2677 VLIB_REGISTER_NODE (tcp4_listen_node) =
2679 .name = "tcp4-listen",
2680 /* Takes a vector of packets. */
2681 .vector_size = sizeof (u32),
2682 .n_errors = TCP_N_ERROR,
2683 .error_strings = tcp_error_strings,
2684 .n_next_nodes = TCP_LISTEN_N_NEXT,
2687 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2688 foreach_tcp_state_next
2691 .format_trace = format_tcp_rx_trace_short,
2696 VLIB_REGISTER_NODE (tcp6_listen_node) =
2698 .name = "tcp6-listen",
2699 /* Takes a vector of packets. */
2700 .vector_size = sizeof (u32),
2701 .n_errors = TCP_N_ERROR,
2702 .error_strings = tcp_error_strings,
2703 .n_next_nodes = TCP_LISTEN_N_NEXT,
2706 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2707 foreach_tcp_state_next
2710 .format_trace = format_tcp_rx_trace_short,
2714 typedef enum _tcp_input_next
2716 TCP_INPUT_NEXT_DROP,
2717 TCP_INPUT_NEXT_LISTEN,
2718 TCP_INPUT_NEXT_RCV_PROCESS,
2719 TCP_INPUT_NEXT_SYN_SENT,
2720 TCP_INPUT_NEXT_ESTABLISHED,
2721 TCP_INPUT_NEXT_RESET,
2722 TCP_INPUT_NEXT_PUNT,
2726 #define foreach_tcp4_input_next \
2727 _ (DROP, "ip4-drop") \
2728 _ (LISTEN, "tcp4-listen") \
2729 _ (RCV_PROCESS, "tcp4-rcv-process") \
2730 _ (SYN_SENT, "tcp4-syn-sent") \
2731 _ (ESTABLISHED, "tcp4-established") \
2732 _ (RESET, "tcp4-reset") \
2733 _ (PUNT, "ip4-punt")
2735 #define foreach_tcp6_input_next \
2736 _ (DROP, "ip6-drop") \
2737 _ (LISTEN, "tcp6-listen") \
2738 _ (RCV_PROCESS, "tcp6-rcv-process") \
2739 _ (SYN_SENT, "tcp6-syn-sent") \
2740 _ (ESTABLISHED, "tcp6-established") \
2741 _ (RESET, "tcp6-reset") \
2742 _ (PUNT, "ip6-punt")
2744 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2747 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2748 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2750 tcp_connection_t *tc;
2755 for (i = 0; i < n_bufs; i++)
2757 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2759 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2760 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2762 tcp = vlib_buffer_get_current (bs[i]);
2763 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2769 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2771 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2773 *next = TCP_INPUT_NEXT_DROP;
2775 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2777 *next = TCP_INPUT_NEXT_PUNT;
2778 *error = TCP_ERROR_PUNT;
2782 *next = TCP_INPUT_NEXT_RESET;
2783 *error = TCP_ERROR_NO_LISTENER;
2788 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2789 vlib_buffer_t * b, u16 * next,
2790 vlib_node_runtime_t * error_node)
2796 tcp = tcp_buffer_hdr (b);
2797 flags = tcp->flags & filter_flags;
2798 *next = tm->dispatch_table[tc->state][flags].next;
2799 error = tm->dispatch_table[tc->state][flags].error;
2802 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2804 b->error = error_node->errors[error];
2805 if (error == TCP_ERROR_DISPATCH)
2806 clib_warning ("tcp conn %u disp error state %U flags %U",
2807 tc->c_c_index, format_tcp_state, tc->state,
2808 format_tcp_flags, (int) flags);
2813 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2814 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2816 u32 n_left_from, *from, thread_index = vm->thread_index;
2817 tcp_main_t *tm = vnet_get_tcp_main ();
2818 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2819 u16 nexts[VLIB_FRAME_SIZE], *next;
2821 tcp_set_time_now (tcp_get_worker (thread_index));
2823 from = vlib_frame_vector_args (frame);
2824 n_left_from = frame->n_vectors;
2825 vlib_get_buffers (vm, from, bufs, n_left_from);
2830 while (n_left_from >= 4)
2832 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2833 tcp_connection_t *tc0, *tc1;
2836 vlib_prefetch_buffer_header (b[2], STORE);
2837 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2839 vlib_prefetch_buffer_header (b[3], STORE);
2840 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2843 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2845 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2847 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2850 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2852 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2853 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2855 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2856 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2858 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2859 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2863 if (PREDICT_TRUE (tc0 != 0))
2865 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2866 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2867 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2871 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2872 b[0]->error = node->errors[error0];
2875 if (PREDICT_TRUE (tc1 != 0))
2877 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2878 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2879 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2883 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2884 b[1]->error = node->errors[error1];
2892 while (n_left_from > 0)
2894 tcp_connection_t *tc0;
2895 u32 error0 = TCP_ERROR_NO_LISTENER;
2897 if (n_left_from > 1)
2899 vlib_prefetch_buffer_header (b[1], STORE);
2900 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2903 next[0] = TCP_INPUT_NEXT_DROP;
2904 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2906 if (PREDICT_TRUE (tc0 != 0))
2908 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2909 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2910 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2914 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2915 b[0]->error = node->errors[error0];
2923 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2924 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2926 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2927 return frame->n_vectors;
2930 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2931 vlib_node_runtime_t * node,
2932 vlib_frame_t * from_frame)
2934 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2935 1 /* is_nolookup */ );
2938 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2939 vlib_node_runtime_t * node,
2940 vlib_frame_t * from_frame)
2942 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2943 1 /* is_nolookup */ );
2947 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2949 .name = "tcp4-input-nolookup",
2950 /* Takes a vector of packets. */
2951 .vector_size = sizeof (u32),
2952 .n_errors = TCP_N_ERROR,
2953 .error_strings = tcp_error_strings,
2954 .n_next_nodes = TCP_INPUT_N_NEXT,
2957 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2958 foreach_tcp4_input_next
2961 .format_buffer = format_tcp_header,
2962 .format_trace = format_tcp_rx_trace,
2967 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2969 .name = "tcp6-input-nolookup",
2970 /* Takes a vector of packets. */
2971 .vector_size = sizeof (u32),
2972 .n_errors = TCP_N_ERROR,
2973 .error_strings = tcp_error_strings,
2974 .n_next_nodes = TCP_INPUT_N_NEXT,
2977 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2978 foreach_tcp6_input_next
2981 .format_buffer = format_tcp_header,
2982 .format_trace = format_tcp_rx_trace,
2986 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2987 vlib_frame_t * from_frame)
2989 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2990 0 /* is_nolookup */ );
2993 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2994 vlib_frame_t * from_frame)
2996 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2997 0 /* is_nolookup */ );
3001 VLIB_REGISTER_NODE (tcp4_input_node) =
3003 .name = "tcp4-input",
3004 /* Takes a vector of packets. */
3005 .vector_size = sizeof (u32),
3006 .n_errors = TCP_N_ERROR,
3007 .error_strings = tcp_error_strings,
3008 .n_next_nodes = TCP_INPUT_N_NEXT,
3011 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3012 foreach_tcp4_input_next
3015 .format_buffer = format_tcp_header,
3016 .format_trace = format_tcp_rx_trace,
3021 VLIB_REGISTER_NODE (tcp6_input_node) =
3023 .name = "tcp6-input",
3024 /* Takes a vector of packets. */
3025 .vector_size = sizeof (u32),
3026 .n_errors = TCP_N_ERROR,
3027 .error_strings = tcp_error_strings,
3028 .n_next_nodes = TCP_INPUT_N_NEXT,
3031 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3032 foreach_tcp6_input_next
3035 .format_buffer = format_tcp_header,
3036 .format_trace = format_tcp_rx_trace,
3040 #ifndef CLIB_MARCH_VARIANT
3042 tcp_dispatch_table_init (tcp_main_t * tm)
3045 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3046 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3048 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3049 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3052 #define _(t,f,n,e) \
3054 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3055 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3058 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3059 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3060 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3061 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3062 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3063 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3064 TCP_ERROR_ACK_INVALID);
3065 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3066 TCP_ERROR_SEGMENT_INVALID);
3067 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3068 TCP_ERROR_SEGMENT_INVALID);
3069 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3070 TCP_ERROR_INVALID_CONNECTION);
3071 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3072 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3073 TCP_ERROR_SEGMENT_INVALID);
3074 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3075 TCP_ERROR_SEGMENT_INVALID);
3076 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3077 TCP_ERROR_SEGMENT_INVALID);
3078 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3079 TCP_ERROR_SEGMENT_INVALID);
3080 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3081 TCP_ERROR_SEGMENT_INVALID);
3082 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3083 TCP_ERROR_SEGMENT_INVALID);
3084 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3085 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3086 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3087 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3088 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3089 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3091 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3092 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3094 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3096 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3097 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3098 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3099 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3101 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3103 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3104 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3105 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3107 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3108 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3109 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3110 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3111 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3112 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3113 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3114 /* SYN-ACK for a SYN */
3115 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3117 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3118 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3119 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3121 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3122 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3124 /* ACK for for established connection -> tcp-established. */
3125 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3126 /* FIN for for established connection -> tcp-established. */
3127 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3128 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3130 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3132 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3133 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3134 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3136 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3137 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3138 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3139 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3140 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3141 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3142 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3143 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3145 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3146 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3148 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3150 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3151 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3152 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3153 /* ACK or FIN-ACK to our FIN */
3154 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3155 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3157 /* FIN in reply to our FIN from the other side */
3158 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3159 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3160 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3162 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3163 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3164 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3165 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3166 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3167 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3168 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3170 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3171 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3172 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3173 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3175 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3177 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3178 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3179 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3180 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3182 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3183 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3184 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3185 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3187 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3189 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3190 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3191 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3192 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3194 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3195 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3197 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3199 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3200 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3201 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3203 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3204 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3205 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3206 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3207 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3208 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3209 /* FIN confirming that the peer (app) has closed */
3210 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3211 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3212 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3214 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3215 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3217 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3218 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3221 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3226 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3227 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3230 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3232 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3233 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3236 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3237 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3238 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3239 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3240 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3241 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3242 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3243 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3245 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3246 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3248 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3250 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3251 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3252 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3253 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3254 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3256 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3257 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3259 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3260 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3261 * incoming segment not containing a RST causes a RST to be sent in
3263 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3264 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3265 TCP_ERROR_CONNECTION_CLOSED);
3266 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3267 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3268 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3269 TCP_ERROR_CONNECTION_CLOSED);
3273 static clib_error_t *
3274 tcp_input_init (vlib_main_t * vm)
3276 clib_error_t *error = 0;
3277 tcp_main_t *tm = vnet_get_tcp_main ();
3279 if ((error = vlib_call_init_function (vm, tcp_init)))
3282 /* Initialize dispatch table. */
3283 tcp_dispatch_table_init (tm);
3288 VLIB_INIT_FUNCTION (tcp_input_init);
3290 #endif /* CLIB_MARCH_VARIANT */
3293 * fd.io coding-style-patch-verification: ON
3296 * eval: (c-set-style "gnu")