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 vlib_error_desc_t tcp_input_error_counters[] = {
25 #define tcp_error(f, n, s, d) { #n, d, VL_COUNTER_SEVERITY_##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_tstamp (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_tstamp (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 += rs->delivered;
875 tc->rcv_dupacks += 1;
876 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
878 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
881 tc->prr_delivered += clib_min (tc->snd_mss,
882 tc->snd_nxt - tc->snd_una);
884 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
888 /* If partial ack, assume that the first un-acked segment was lost */
889 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
890 tcp_fastrecovery_first_on (tc);
894 * See if we can exit and stop retransmitting
896 if (seq_geq (tc->snd_una, tc->snd_congestion))
898 /* If spurious return, we've already updated everything */
899 if (tcp_cc_recover (tc))
901 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
905 /* Treat as congestion avoidance ack */
906 tcp_cc_rcv_ack (tc, rs);
910 tcp_program_retransmit (tc);
913 * Notify cc of the event
916 if (!tc->bytes_acked)
918 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
922 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
923 * reset dupacks to 0. Also needed if in congestion recovery */
926 if (tcp_in_recovery (tc))
927 tcp_cc_rcv_ack (tc, rs);
929 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
933 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
935 if (!tcp_in_cong_recovery (tc))
938 if (tcp_opts_sack_permitted (&tc->rcv_opts))
939 tcp_rcv_sacks (tc, tc->snd_una);
943 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
944 tcp_bt_sample_delivery_rate (tc, rs);
946 tcp_cc_handle_event (tc, rs, 1);
950 * Check if duplicate ack as per RFC5681 Sec. 2
953 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
956 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
957 && seq_gt (tc->snd_nxt, tc->snd_una)
958 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
959 && (prev_snd_wnd == tc->snd_wnd));
963 * Checks if ack is a congestion control event.
966 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
967 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
969 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
970 * defined to be 'duplicate' as well */
971 *is_dack = tc->sack_sb.last_sacked_bytes
972 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
974 return (*is_dack || tcp_in_cong_recovery (tc));
978 * Process incoming ACK
981 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
982 tcp_header_t * th, u32 * error)
984 u32 prev_snd_wnd, prev_snd_una;
985 tcp_rate_sample_t rs = { 0 };
988 TCP_EVT (TCP_EVT_CC_STAT, tc);
990 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
991 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
993 /* We've probably entered recovery and the peer still has some
994 * of the data we've sent. Update snd_nxt and accept the ack */
995 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
996 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
998 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1002 tc->errors.above_ack_wnd += 1;
1003 *error = TCP_ERROR_ACK_FUTURE;
1004 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1008 /* If old ACK, probably it's an old dupack */
1009 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1011 tc->errors.below_ack_wnd += 1;
1012 *error = TCP_ERROR_ACK_OLD;
1013 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1015 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1018 tcp_handle_old_ack (tc, &rs);
1020 /* Don't drop yet */
1027 * Looks okay, process feedback
1030 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1031 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1033 prev_snd_wnd = tc->snd_wnd;
1034 prev_snd_una = tc->snd_una;
1035 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1036 vnet_buffer (b)->tcp.ack_number,
1037 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1038 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1039 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1040 tcp_validate_txf_size (tc, tc->bytes_acked);
1042 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1043 tcp_bt_sample_delivery_rate (tc, &rs);
1045 rs.delivered = tc->bytes_acked + tc->sack_sb.last_sacked_bytes -
1046 tc->sack_sb.last_bytes_delivered;
1048 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1050 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1051 if (tc->bytes_acked)
1052 tcp_program_dequeue (wrk, tc);
1055 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1058 * Check if we have congestion event
1061 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1063 tcp_cc_handle_event (tc, &rs, is_dack);
1064 tc->dupacks_in += is_dack;
1065 if (!tcp_in_cong_recovery (tc))
1067 *error = TCP_ERROR_ACK_OK;
1070 *error = TCP_ERROR_ACK_DUP;
1071 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1077 * Update congestion control (slow start/congestion avoidance)
1079 tcp_cc_update (tc, &rs);
1080 *error = TCP_ERROR_ACK_OK;
1085 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1087 if (!tcp_disconnect_pending (tc))
1089 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1090 tcp_disconnect_pending_on (tc);
1095 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1097 u32 thread_index, *pending_disconnects, *pending_resets;
1098 tcp_connection_t *tc;
1101 if (vec_len (wrk->pending_disconnects))
1103 thread_index = wrk->vm->thread_index;
1104 pending_disconnects = wrk->pending_disconnects;
1105 for (i = 0; i < vec_len (pending_disconnects); i++)
1107 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1108 tcp_disconnect_pending_off (tc);
1109 session_transport_closing_notify (&tc->connection);
1111 _vec_len (wrk->pending_disconnects) = 0;
1114 if (vec_len (wrk->pending_resets))
1116 thread_index = wrk->vm->thread_index;
1117 pending_resets = wrk->pending_resets;
1118 for (i = 0; i < vec_len (pending_resets); i++)
1120 tc = tcp_connection_get (pending_resets[i], thread_index);
1121 tcp_disconnect_pending_off (tc);
1122 tcp_handle_rst (tc);
1124 _vec_len (wrk->pending_resets) = 0;
1129 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1132 /* Reject out-of-order fins */
1133 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1136 /* Account for the FIN and send ack */
1138 tc->flags |= TCP_CONN_FINRCVD;
1139 tcp_program_ack (tc);
1140 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1141 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1142 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1143 tcp_program_disconnect (wrk, tc);
1144 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1145 tcp_cfg.closewait_time);
1146 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1147 *error = TCP_ERROR_FIN_RCVD;
1150 /** Enqueue data for delivery to application */
1152 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1155 int written, error = TCP_ERROR_ENQUEUED;
1157 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1159 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1160 1 /* queue event */ , 1);
1161 tc->bytes_in += written;
1163 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1165 /* Update rcv_nxt */
1166 if (PREDICT_TRUE (written == data_len))
1168 tc->rcv_nxt += written;
1170 /* If more data written than expected, account for out-of-order bytes. */
1171 else if (written > data_len)
1173 tc->rcv_nxt += written;
1174 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1176 else if (written > 0)
1178 /* We've written something but FIFO is probably full now */
1179 tc->rcv_nxt += written;
1180 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1184 /* Packet made it through for ack processing */
1185 if (tc->rcv_wnd < tc->snd_mss)
1186 return TCP_ERROR_ZERO_RWND;
1188 return TCP_ERROR_FIFO_FULL;
1191 /* Update SACK list if need be */
1192 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
1194 /* Remove SACK blocks that have been delivered */
1195 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1201 /** Enqueue out-of-order data */
1203 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1209 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1212 /* Enqueue out-of-order data with relative offset */
1213 rv = session_enqueue_stream_connection (&tc->connection, b,
1214 vnet_buffer (b)->tcp.seq_number -
1215 tc->rcv_nxt, 0 /* queue event */ ,
1218 /* Nothing written */
1221 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1222 return TCP_ERROR_FIFO_FULL;
1225 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1226 tc->bytes_in += data_len;
1228 /* Update SACK list if in use */
1229 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1231 ooo_segment_t *newest;
1234 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1236 /* Get the newest segment from the fifo */
1237 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1240 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1241 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1242 start = tc->rcv_nxt + offset;
1243 end = start + ooo_segment_length (s0->rx_fifo, newest);
1244 tcp_update_sack_list (tc, start, end);
1245 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1246 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1250 return TCP_ERROR_ENQUEUED_OOO;
1254 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1256 u32 discard, first = b->current_length;
1257 vlib_main_t *vm = vlib_get_main ();
1259 /* Handle multi-buffer segments */
1260 if (n_bytes_to_drop > b->current_length)
1262 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1266 discard = clib_min (n_bytes_to_drop, b->current_length);
1267 vlib_buffer_advance (b, discard);
1268 b = vlib_get_buffer (vm, b->next_buffer);
1269 n_bytes_to_drop -= discard;
1271 while (n_bytes_to_drop);
1272 if (n_bytes_to_drop > first)
1273 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1276 vlib_buffer_advance (b, n_bytes_to_drop);
1277 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1282 * Receive buffer for connection and handle acks
1284 * It handles both in order or out-of-order data.
1287 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1290 u32 error, n_bytes_to_drop, n_data_bytes;
1292 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1293 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1294 ASSERT (n_data_bytes);
1295 tc->data_segs_in += 1;
1297 /* Make sure we don't consume trailing bytes */
1298 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1299 b->current_length = n_data_bytes;
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 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1483 u16 err_counters[TCP_N_ERROR] = { 0 };
1484 u32 n_left_from, *from;
1486 if (node->flags & VLIB_NODE_FLAG_TRACE)
1487 tcp_established_trace_frame (vm, node, frame, is_ip4);
1489 from = vlib_frame_vector_args (frame);
1490 n_left_from = frame->n_vectors;
1492 vlib_get_buffers (vm, from, bufs, n_left_from);
1495 while (n_left_from > 0)
1497 u32 error = TCP_ERROR_ACK_OK;
1498 tcp_connection_t *tc;
1501 if (n_left_from > 1)
1503 vlib_prefetch_buffer_header (b[1], LOAD);
1504 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1507 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1510 if (PREDICT_FALSE (tc == 0))
1512 error = TCP_ERROR_INVALID_CONNECTION;
1516 th = tcp_buffer_hdr (b[0]);
1518 /* TODO header prediction fast path */
1520 /* 1-4: check SEQ, RST, SYN */
1521 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1523 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1527 /* 5: check the ACK field */
1528 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1531 /* 6: check the URG bit TODO */
1533 /* 7: process the segment text */
1534 if (vnet_buffer (b[0])->tcp.data_len)
1535 error = tcp_segment_rcv (wrk, tc, b[0]);
1537 /* 8: check the FIN bit */
1538 if (PREDICT_FALSE (tcp_is_fin (th)))
1539 tcp_rcv_fin (wrk, tc, b[0], &error);
1542 tcp_inc_err_counter (err_counters, error, 1);
1548 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1550 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1551 tcp_store_err_counters (established, err_counters);
1552 tcp_handle_postponed_dequeues (wrk);
1553 tcp_handle_disconnects (wrk);
1554 vlib_buffer_free (vm, from, frame->n_vectors);
1556 return frame->n_vectors;
1559 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1560 vlib_node_runtime_t * node,
1561 vlib_frame_t * from_frame)
1563 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1566 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1567 vlib_node_runtime_t * node,
1568 vlib_frame_t * from_frame)
1570 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1574 VLIB_REGISTER_NODE (tcp4_established_node) =
1576 .name = "tcp4-established",
1577 /* Takes a vector of packets. */
1578 .vector_size = sizeof (u32),
1579 .n_errors = TCP_N_ERROR,
1580 .error_counters = tcp_input_error_counters,
1581 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1584 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1585 foreach_tcp_state_next
1588 .format_trace = format_tcp_rx_trace_short,
1593 VLIB_REGISTER_NODE (tcp6_established_node) =
1595 .name = "tcp6-established",
1596 /* Takes a vector of packets. */
1597 .vector_size = sizeof (u32),
1598 .n_errors = TCP_N_ERROR,
1599 .error_counters = tcp_input_error_counters,
1600 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1603 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1604 foreach_tcp_state_next
1607 .format_trace = format_tcp_rx_trace_short,
1613 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1616 transport_connection_t *tmp = 0;
1623 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1626 u8 is_ip_valid = 0, val_l, val_r;
1628 if (tc->connection.is_ip4)
1630 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1632 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1633 &tc->connection.lcl_ip.ip4);
1634 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1635 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1636 &tc->connection.rmt_ip.ip4);
1637 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1638 is_ip_valid = val_l && val_r;
1642 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1644 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1645 &tc->connection.lcl_ip.ip6);
1646 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1647 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1648 &tc->connection.rmt_ip.ip6);
1649 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1650 is_ip_valid = val_l && val_r;
1653 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1654 && (tc->state == TCP_STATE_LISTEN
1655 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1659 handle = session_lookup_half_open_handle (&tc->connection);
1660 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1661 tc->c_proto, tc->c_is_ip4);
1665 if (tmp->lcl_port == hdr->dst_port
1666 && tmp->rmt_port == hdr->src_port)
1668 TCP_DBG ("half-open is valid!");
1677 * Lookup transport connection
1679 static tcp_connection_t *
1680 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1684 transport_connection_t *tconn;
1685 tcp_connection_t *tc;
1690 ip4 = vlib_buffer_get_current (b);
1691 tcp = ip4_next_header (ip4);
1692 tconn = session_lookup_connection_wt4 (fib_index,
1697 TRANSPORT_PROTO_TCP,
1698 thread_index, &is_filtered);
1699 tc = tcp_get_connection_from_transport (tconn);
1700 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1705 ip6 = vlib_buffer_get_current (b);
1706 tcp = ip6_next_header (ip6);
1707 tconn = session_lookup_connection_wt6 (fib_index,
1712 TRANSPORT_PROTO_TCP,
1713 thread_index, &is_filtered);
1714 tc = tcp_get_connection_from_transport (tconn);
1715 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1720 static tcp_connection_t *
1721 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1727 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1728 tcp_header_t *tcp = tcp_buffer_hdr (b);
1729 s = session_lookup_listener4 (fib_index,
1731 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1735 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1736 tcp_header_t *tcp = tcp_buffer_hdr (b);
1737 s = session_lookup_listener6 (fib_index,
1739 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1742 if (PREDICT_TRUE (s != 0))
1743 return tcp_get_connection_from_transport (transport_get_listener
1744 (TRANSPORT_PROTO_TCP,
1745 s->connection_index));
1751 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1752 u32 *from, u32 n_bufs)
1754 tcp_connection_t *tc = 0;
1759 for (i = 0; i < n_bufs; i++)
1761 b = vlib_get_buffer (vm, from[i]);
1762 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1765 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1766 t = vlib_add_trace (vm, node, b, sizeof (*t));
1767 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1772 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1774 vnet_main_t *vnm = vnet_get_main ();
1775 const dpo_id_t *dpo;
1776 const load_balance_t *lb;
1777 vnet_hw_interface_t *hw_if;
1778 u32 sw_if_idx, lb_idx;
1782 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1783 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1787 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1788 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1791 lb = load_balance_get (lb_idx);
1792 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1794 dpo = load_balance_get_bucket_i (lb, 0);
1796 sw_if_idx = dpo_get_urpf (dpo);
1797 if (PREDICT_FALSE (sw_if_idx == ~0))
1800 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1801 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1802 tc->cfg_flags |= TCP_CFG_F_TSO;
1806 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1807 vlib_frame_t *frame, int is_ip4)
1809 u32 n_left_from, *from, thread_index = vm->thread_index, errors = 0;
1810 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1811 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1813 from = vlib_frame_vector_args (frame);
1814 n_left_from = frame->n_vectors;
1816 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1817 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1819 vlib_get_buffers (vm, from, bufs, n_left_from);
1822 while (n_left_from > 0)
1824 u32 ack, seq, error = TCP_ERROR_NONE;
1825 tcp_connection_t *tc, *new_tc;
1828 tc = tcp_half_open_connection_get (
1829 vnet_buffer (b[0])->tcp.connection_index);
1830 if (PREDICT_FALSE (tc == 0))
1832 error = TCP_ERROR_INVALID_CONNECTION;
1836 /* Half-open completed or cancelled recently but the connection
1837 * was't removed yet by the owning thread */
1838 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1840 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1844 ack = vnet_buffer (b[0])->tcp.ack_number;
1845 seq = vnet_buffer (b[0])->tcp.seq_number;
1846 tcp = tcp_buffer_hdr (b[0]);
1848 /* Crude check to see if the connection handle does not match
1849 * the packet. Probably connection just switched to established */
1850 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1851 tcp->src_port != tc->c_rmt_port))
1853 error = TCP_ERROR_INVALID_CONNECTION;
1857 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1859 error = TCP_ERROR_SEGMENT_INVALID;
1863 /* SYNs consume sequence numbers */
1864 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1867 * 1. check the ACK bit
1871 * If the ACK bit is set
1872 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1873 * the RST bit is set, if so drop the segment and return)
1874 * <SEQ=SEG.ACK><CTL=RST>
1875 * and discard the segment. Return.
1876 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1880 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1883 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1884 error = TCP_ERROR_RCV_WND;
1888 /* Make sure ACK is valid */
1889 if (seq_gt (tc->snd_una, ack))
1891 error = TCP_ERROR_ACK_INVALID;
1897 * 2. check the RST bit
1902 /* If ACK is acceptable, signal client that peer is not
1903 * willing to accept connection and drop connection*/
1905 tcp_rcv_rst (wrk, tc);
1906 error = TCP_ERROR_RST_RCVD;
1911 * 3. check the security and precedence (skipped)
1915 * 4. check the SYN bit
1918 /* No SYN flag. Drop. */
1921 error = TCP_ERROR_SEGMENT_INVALID;
1926 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1928 error = TCP_ERROR_OPTIONS;
1932 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1933 * current thread pool. */
1934 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1935 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1937 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1939 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1941 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1942 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1945 if (tcp_opts_wscale (&new_tc->rcv_opts))
1946 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1948 new_tc->rcv_wscale = 0;
1950 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1951 << new_tc->snd_wscale;
1952 new_tc->snd_wl1 = seq;
1953 new_tc->snd_wl2 = ack;
1955 tcp_connection_init_vars (new_tc);
1957 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1958 if (PREDICT_TRUE (tcp_ack (tcp)))
1960 /* Our SYN is ACKed: we have iss < ack = snd_una */
1962 /* TODO Dequeue acknowledged segments if we support Fast Open */
1963 new_tc->snd_una = ack;
1964 new_tc->state = TCP_STATE_ESTABLISHED;
1966 /* Make sure las is initialized for the wnd computation */
1967 new_tc->rcv_las = new_tc->rcv_nxt;
1969 /* Notify app that we have connection. If session layer can't
1970 * allocate session send reset */
1971 if (session_stream_connect_notify (&new_tc->connection,
1974 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1975 tcp_connection_cleanup (new_tc);
1976 error = TCP_ERROR_CREATE_SESSION_FAIL;
1980 transport_fifos_init_ooo (&new_tc->connection);
1981 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1982 /* Update rtt with the syn-ack sample */
1983 tcp_estimate_initial_rtt (new_tc);
1984 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1985 error = TCP_ERROR_SYN_ACKS_RCVD;
1987 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1990 new_tc->state = TCP_STATE_SYN_RCVD;
1992 /* Notify app that we have connection */
1993 if (session_stream_connect_notify (&new_tc->connection,
1996 tcp_connection_cleanup (new_tc);
1997 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1998 TCP_EVT (TCP_EVT_RST_SENT, tc);
1999 error = TCP_ERROR_CREATE_SESSION_FAIL;
2003 transport_fifos_init_ooo (&new_tc->connection);
2004 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
2006 tcp_init_snd_vars (new_tc);
2007 tcp_send_synack (new_tc);
2008 error = TCP_ERROR_SYNS_RCVD;
2012 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
2013 tcp_check_tx_offload (new_tc, is_ip4);
2015 /* Read data, if any */
2016 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
2018 clib_warning ("rcvd data in syn-sent");
2019 error = tcp_segment_rcv (wrk, new_tc, b[0]);
2020 if (error == TCP_ERROR_ACK_OK)
2021 error = TCP_ERROR_SYN_ACKS_RCVD;
2025 /* Send ack now instead of programming it because connection was
2026 * just established and it's not optional. */
2027 tcp_send_ack (new_tc);
2032 /* If this is not the owning thread, wait for syn retransmit to
2033 * expire and cleanup then */
2034 if (tcp_half_open_connection_cleanup (tc))
2035 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
2041 tcp_inc_counter (syn_sent, error, 1);
2045 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2046 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2047 vlib_buffer_free (vm, from, frame->n_vectors);
2048 tcp_handle_disconnects (wrk);
2050 return frame->n_vectors;
2053 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2054 vlib_node_runtime_t * node,
2055 vlib_frame_t * from_frame)
2057 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2060 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2061 vlib_node_runtime_t * node,
2062 vlib_frame_t * from_frame)
2064 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2068 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2070 .name = "tcp4-syn-sent",
2071 /* Takes a vector of packets. */
2072 .vector_size = sizeof (u32),
2073 .n_errors = TCP_N_ERROR,
2074 .error_counters = tcp_input_error_counters,
2075 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2078 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2079 foreach_tcp_state_next
2082 .format_trace = format_tcp_rx_trace_short,
2087 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2089 .name = "tcp6-syn-sent",
2090 /* Takes a vector of packets. */
2091 .vector_size = sizeof (u32),
2092 .n_errors = TCP_N_ERROR,
2093 .error_counters = tcp_input_error_counters,
2094 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2097 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2098 foreach_tcp_state_next
2101 .format_trace = format_tcp_rx_trace_short,
2106 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2107 u32 *from, u32 n_bufs)
2109 u32 thread_index = vm->thread_index;
2110 tcp_connection_t *tc = 0;
2115 for (i = 0; i < n_bufs; i++)
2117 b = vlib_get_buffer (vm, from[i]);
2118 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2120 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2122 t = vlib_add_trace (vm, node, b, sizeof (*t));
2123 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2128 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2129 * as per RFC793 p. 64
2132 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2133 vlib_frame_t *frame, int is_ip4)
2135 u32 thread_index = vm->thread_index, errors, n_left_from, *from, max_deq;
2136 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2137 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2139 from = vlib_frame_vector_args (frame);
2140 n_left_from = frame->n_vectors;
2142 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2143 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2145 vlib_get_buffers (vm, from, bufs, n_left_from);
2148 while (n_left_from > 0)
2150 u32 error = TCP_ERROR_NONE;
2151 tcp_header_t *tcp = 0;
2152 tcp_connection_t *tc;
2155 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2157 if (PREDICT_FALSE (tc == 0))
2159 error = TCP_ERROR_INVALID_CONNECTION;
2163 tcp = tcp_buffer_hdr (b[0]);
2164 is_fin = tcp_is_fin (tcp);
2168 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2170 tcp_connection_t *tmp;
2171 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2173 if (tmp->state != tc->state)
2175 if (tc->state != TCP_STATE_CLOSED)
2176 clib_warning ("state changed");
2183 * Special treatment for CLOSED
2185 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2187 error = TCP_ERROR_CONNECTION_CLOSED;
2192 * For all other states (except LISTEN)
2195 /* 1-4: check SEQ, RST, SYN */
2196 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2199 /* 5: check the ACK field */
2202 case TCP_STATE_SYN_RCVD:
2204 /* Make sure the segment is exactly right */
2205 if (tc->rcv_nxt != vnet_buffer (b[0])->tcp.seq_number || is_fin)
2207 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2208 error = TCP_ERROR_SEGMENT_INVALID;
2213 * If the segment acknowledgment is not acceptable, form a
2215 * <SEQ=SEG.ACK><CTL=RST>
2218 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2220 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2221 error = TCP_ERROR_SEGMENT_INVALID;
2225 /* Update rtt and rto */
2226 tcp_estimate_initial_rtt (tc);
2227 tcp_connection_tx_pacer_update (tc);
2229 /* Switch state to ESTABLISHED */
2230 tc->state = TCP_STATE_ESTABLISHED;
2231 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2233 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2234 tcp_check_tx_offload (tc, is_ip4);
2236 /* Initialize session variables */
2237 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2238 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2239 << tc->rcv_opts.wscale;
2240 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2241 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2243 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2244 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2245 if (session_stream_accept_notify (&tc->connection))
2247 error = TCP_ERROR_MSG_QUEUE_FULL;
2248 tcp_send_reset (tc);
2249 session_transport_delete_notify (&tc->connection);
2250 tcp_connection_cleanup (tc);
2253 error = TCP_ERROR_ACK_OK;
2255 case TCP_STATE_ESTABLISHED:
2256 /* We can get packets in established state here because they
2257 * were enqueued before state change */
2258 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2262 case TCP_STATE_FIN_WAIT_1:
2263 /* In addition to the processing for the ESTABLISHED state, if
2264 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2265 * continue processing in that state. */
2266 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2269 /* Still have to send the FIN */
2270 if (tc->flags & TCP_CONN_FINPNDG)
2272 /* TX fifo finally drained */
2273 max_deq = transport_max_tx_dequeue (&tc->connection);
2274 if (max_deq <= tc->burst_acked)
2276 /* If a fin was received and data was acked extend wait */
2277 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2278 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2279 tcp_cfg.closewait_time);
2281 /* If FIN is ACKed */
2282 else if (tc->snd_una == tc->snd_nxt)
2284 /* Stop all retransmit timers because we have nothing more
2286 tcp_connection_timers_reset (tc);
2288 /* We already have a FIN but didn't transition to CLOSING
2289 * because of outstanding tx data. Close the connection. */
2290 if (tc->flags & TCP_CONN_FINRCVD)
2292 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2293 session_transport_closed_notify (&tc->connection);
2294 tcp_program_cleanup (wrk, tc);
2298 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2299 /* Enable waitclose because we're willing to wait for peer's
2300 * FIN but not indefinitely. */
2301 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2302 tcp_cfg.finwait2_time);
2304 /* Don't try to deq the FIN acked */
2305 if (tc->burst_acked > 1)
2306 session_tx_fifo_dequeue_drop (&tc->connection,
2307 tc->burst_acked - 1);
2308 tc->burst_acked = 0;
2311 case TCP_STATE_FIN_WAIT_2:
2312 /* In addition to the processing for the ESTABLISHED state, if
2313 * the retransmission queue is empty, the user's CLOSE can be
2314 * acknowledged ("ok") but do not delete the TCB. */
2315 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2317 tc->burst_acked = 0;
2319 case TCP_STATE_CLOSE_WAIT:
2320 /* Do the same processing as for the ESTABLISHED state. */
2321 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2324 if (!(tc->flags & TCP_CONN_FINPNDG))
2327 /* Still have outstanding tx data */
2328 max_deq = transport_max_tx_dequeue (&tc->connection);
2329 if (max_deq > tc->burst_acked)
2333 tcp_connection_timers_reset (tc);
2334 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2335 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2336 tcp_cfg.lastack_time);
2338 case TCP_STATE_CLOSING:
2339 /* In addition to the processing for the ESTABLISHED state, if
2340 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2341 * otherwise ignore the segment. */
2342 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2345 if (tc->snd_una != tc->snd_nxt)
2348 tcp_connection_timers_reset (tc);
2349 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2350 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2351 tcp_cfg.timewait_time);
2352 session_transport_closed_notify (&tc->connection);
2356 case TCP_STATE_LAST_ACK:
2357 /* The only thing that [should] arrive in this state is an
2358 * acknowledgment of our FIN. If our FIN is now acknowledged,
2359 * delete the TCB, enter the CLOSED state, and return. */
2361 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2364 /* Apparently our ACK for the peer's FIN was lost */
2365 if (is_fin && tc->snd_una != tc->snd_nxt)
2371 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2372 session_transport_closed_notify (&tc->connection);
2374 /* Don't free the connection from the data path since
2375 * we can't ensure that we have no packets already enqueued
2376 * to output. Rely instead on the waitclose timer */
2377 tcp_connection_timers_reset (tc);
2378 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2383 case TCP_STATE_TIME_WAIT:
2384 /* The only thing that can arrive in this state is a
2385 * retransmission of the remote FIN. Acknowledge it, and restart
2386 * the 2 MSL timeout. */
2388 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2394 tcp_program_ack (tc);
2395 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2396 tcp_cfg.timewait_time);
2404 /* 6: check the URG bit TODO */
2406 /* 7: process the segment text */
2409 case TCP_STATE_ESTABLISHED:
2410 case TCP_STATE_FIN_WAIT_1:
2411 case TCP_STATE_FIN_WAIT_2:
2412 if (vnet_buffer (b[0])->tcp.data_len)
2413 error = tcp_segment_rcv (wrk, tc, b[0]);
2414 /* Don't accept out of order fins lower */
2415 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2418 case TCP_STATE_CLOSE_WAIT:
2419 case TCP_STATE_CLOSING:
2420 case TCP_STATE_LAST_ACK:
2421 case TCP_STATE_TIME_WAIT:
2422 /* This should not occur, since a FIN has been received from the
2423 * remote side. Ignore the segment text. */
2427 /* 8: check the FIN bit */
2431 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2435 case TCP_STATE_ESTABLISHED:
2436 /* Account for the FIN and send ack */
2438 tcp_program_ack (tc);
2439 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2440 tcp_program_disconnect (wrk, tc);
2441 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2442 tcp_cfg.closewait_time);
2444 case TCP_STATE_SYN_RCVD:
2445 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2446 * notified yet, set a cleanup timer instead of relying on
2447 * disconnect notify and the implicit close call. */
2448 tcp_connection_timers_reset (tc);
2451 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2452 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2453 tcp_cfg.lastack_time);
2455 case TCP_STATE_CLOSE_WAIT:
2456 case TCP_STATE_CLOSING:
2457 case TCP_STATE_LAST_ACK:
2460 case TCP_STATE_FIN_WAIT_1:
2463 if (tc->flags & TCP_CONN_FINPNDG)
2465 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2466 * sending it. Since we already received a fin, do not wait
2468 tc->flags |= TCP_CONN_FINRCVD;
2469 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2470 tcp_cfg.closewait_time);
2474 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2475 tcp_program_ack (tc);
2476 /* Wait for ACK for our FIN but not forever */
2477 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2478 tcp_cfg.closing_time);
2481 case TCP_STATE_FIN_WAIT_2:
2482 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2484 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2485 tcp_connection_timers_reset (tc);
2486 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2487 tcp_cfg.timewait_time);
2488 tcp_program_ack (tc);
2489 session_transport_closed_notify (&tc->connection);
2491 case TCP_STATE_TIME_WAIT:
2492 /* Remain in the TIME-WAIT state. Restart the time-wait
2495 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2496 tcp_cfg.timewait_time);
2499 error = TCP_ERROR_FIN_RCVD;
2505 tcp_inc_counter (rcv_process, error, 1);
2508 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2510 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2511 tcp_handle_postponed_dequeues (wrk);
2512 tcp_handle_disconnects (wrk);
2513 vlib_buffer_free (vm, from, frame->n_vectors);
2515 return frame->n_vectors;
2518 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2519 vlib_node_runtime_t * node,
2520 vlib_frame_t * from_frame)
2522 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2525 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2526 vlib_node_runtime_t * node,
2527 vlib_frame_t * from_frame)
2529 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2533 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2535 .name = "tcp4-rcv-process",
2536 /* Takes a vector of packets. */
2537 .vector_size = sizeof (u32),
2538 .n_errors = TCP_N_ERROR,
2539 .error_counters = tcp_input_error_counters,
2540 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2543 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2544 foreach_tcp_state_next
2547 .format_trace = format_tcp_rx_trace_short,
2552 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2554 .name = "tcp6-rcv-process",
2555 /* Takes a vector of packets. */
2556 .vector_size = sizeof (u32),
2557 .n_errors = TCP_N_ERROR,
2558 .error_counters = tcp_input_error_counters,
2559 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2562 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2563 foreach_tcp_state_next
2566 .format_trace = format_tcp_rx_trace_short,
2571 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2572 u32 *to_next, u32 n_bufs)
2574 tcp_connection_t *tc = 0;
2579 for (i = 0; i < n_bufs; i++)
2581 b = vlib_get_buffer (vm, to_next[i]);
2582 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2584 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2585 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2586 t = vlib_add_trace (vm, node, b, sizeof (*t));
2587 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2592 * SYN received in TIME-WAIT state.
2595 * "When a connection is [...] on TIME-WAIT state [...]
2596 * [a TCP] MAY accept a new SYN from the remote TCP to
2597 * reopen the connection directly, if it:
2599 * (1) assigns its initial sequence number for the new
2600 * connection to be larger than the largest sequence
2601 * number it used on the previous connection incarnation,
2604 * (2) returns to TIME-WAIT state if the SYN turns out
2605 * to be an old duplicate".
2607 * The function returns true if the syn can be accepted during
2608 * connection time-wait (port reuse). In this case the function
2609 * also calculates what the iss should be for the new connection.
2612 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2614 int paws_reject = tcp_segment_check_paws (tc);
2618 /* Check that the SYN arrived out of window. We accept it */
2620 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2621 (tcp_opts_tstamp (&tc->rcv_opts) &&
2622 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2624 /* Set the iss of the new connection to be the largest sequence number
2625 * the old peer would have accepted and add some random number
2627 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2628 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2638 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2639 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2640 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2641 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2647 * LISTEN state processing as per RFC 793 p. 65
2650 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2651 vlib_frame_t *frame, int is_ip4)
2653 u32 n_left_from, *from, n_syns = 0;
2654 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2655 u32 thread_index = vm->thread_index;
2658 from = vlib_frame_vector_args (frame);
2659 n_left_from = frame->n_vectors;
2661 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2662 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2664 vlib_get_buffers (vm, from, bufs, n_left_from);
2667 while (n_left_from > 0)
2669 u32 error = TCP_ERROR_NONE;
2670 tcp_connection_t *lc, *child;
2672 /* Flags initialized with connection state after lookup */
2673 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2675 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2677 else /* We are in TimeWait state*/
2679 tcp_connection_t *tc;
2680 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2682 if (tc->state != TCP_STATE_TIME_WAIT)
2684 error = TCP_ERROR_CREATE_EXISTS;
2688 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2690 /* This SYN can't be accepted */
2691 error = TCP_ERROR_CREATE_EXISTS;
2695 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2696 /* clean up the old session */
2697 tcp_connection_del (tc);
2698 /* listener was cleaned up */
2701 error = TCP_ERROR_NO_LISTENER;
2706 /* Make sure connection wasn't just created */
2708 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2709 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2711 error = TCP_ERROR_CREATE_EXISTS;
2715 /* Create child session. For syn-flood protection use filter */
2717 /* 1. first check for an RST: handled by input dispatch */
2719 /* 2. second check for an ACK: handled by input dispatch */
2721 /* 3. check for a SYN (did that already) */
2723 /* Create child session and send SYN-ACK */
2724 child = tcp_connection_alloc (thread_index);
2726 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2728 error = TCP_ERROR_OPTIONS;
2729 tcp_connection_free (child);
2733 tcp_init_w_buffer (child, b[0], is_ip4);
2735 child->state = TCP_STATE_SYN_RCVD;
2736 child->c_fib_index = lc->c_fib_index;
2737 child->cc_algo = lc->cc_algo;
2739 /* In the regular case, the tw_iss will be zero, but
2740 * in the special case of syn arriving in time_wait state, the value
2741 * will be set according to rfc 1122
2743 child->iss = tw_iss;
2744 tcp_connection_init_vars (child);
2745 child->rto = TCP_RTO_MIN;
2748 * This initializes elog track, must be done before synack.
2749 * We also do it before possible tcp_connection_cleanup() as it
2750 * generates TCP_EVT_DELETE event.
2752 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2754 if (session_stream_accept (&child->connection, lc->c_s_index,
2755 lc->c_thread_index, 0 /* notify */ ))
2757 tcp_connection_cleanup (child);
2758 error = TCP_ERROR_CREATE_SESSION_FAIL;
2762 transport_fifos_init_ooo (&child->connection);
2763 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2765 tcp_send_synack (child);
2771 n_syns += (error == TCP_ERROR_NONE);
2774 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2775 vlib_buffer_free (vm, from, frame->n_vectors);
2777 return frame->n_vectors;
2780 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2781 vlib_frame_t * from_frame)
2783 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2786 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2787 vlib_frame_t * from_frame)
2789 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2793 VLIB_REGISTER_NODE (tcp4_listen_node) =
2795 .name = "tcp4-listen",
2796 /* Takes a vector of packets. */
2797 .vector_size = sizeof (u32),
2798 .n_errors = TCP_N_ERROR,
2799 .error_counters = tcp_input_error_counters,
2800 .n_next_nodes = TCP_LISTEN_N_NEXT,
2803 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2804 foreach_tcp_state_next
2807 .format_trace = format_tcp_rx_trace_short,
2812 VLIB_REGISTER_NODE (tcp6_listen_node) =
2814 .name = "tcp6-listen",
2815 /* Takes a vector of packets. */
2816 .vector_size = sizeof (u32),
2817 .n_errors = TCP_N_ERROR,
2818 .error_counters = tcp_input_error_counters,
2819 .n_next_nodes = TCP_LISTEN_N_NEXT,
2822 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2823 foreach_tcp_state_next
2826 .format_trace = format_tcp_rx_trace_short,
2830 typedef enum _tcp_input_next
2832 TCP_INPUT_NEXT_DROP,
2833 TCP_INPUT_NEXT_LISTEN,
2834 TCP_INPUT_NEXT_RCV_PROCESS,
2835 TCP_INPUT_NEXT_SYN_SENT,
2836 TCP_INPUT_NEXT_ESTABLISHED,
2837 TCP_INPUT_NEXT_RESET,
2838 TCP_INPUT_NEXT_PUNT,
2842 #define foreach_tcp4_input_next \
2843 _ (DROP, "ip4-drop") \
2844 _ (LISTEN, "tcp4-listen") \
2845 _ (RCV_PROCESS, "tcp4-rcv-process") \
2846 _ (SYN_SENT, "tcp4-syn-sent") \
2847 _ (ESTABLISHED, "tcp4-established") \
2848 _ (RESET, "tcp4-reset") \
2849 _ (PUNT, "ip4-punt")
2851 #define foreach_tcp6_input_next \
2852 _ (DROP, "ip6-drop") \
2853 _ (LISTEN, "tcp6-listen") \
2854 _ (RCV_PROCESS, "tcp6-rcv-process") \
2855 _ (SYN_SENT, "tcp6-syn-sent") \
2856 _ (ESTABLISHED, "tcp6-established") \
2857 _ (RESET, "tcp6-reset") \
2858 _ (PUNT, "ip6-punt")
2860 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2863 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2864 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2866 tcp_connection_t *tc;
2871 for (i = 0; i < n_bufs; i++)
2873 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2875 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2876 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2878 tcp = vlib_buffer_get_current (bs[i]);
2879 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2885 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2887 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2889 *next = TCP_INPUT_NEXT_DROP;
2891 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2893 *next = TCP_INPUT_NEXT_PUNT;
2894 *error = TCP_ERROR_PUNT;
2898 *next = TCP_INPUT_NEXT_RESET;
2899 *error = TCP_ERROR_NO_LISTENER;
2904 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2905 vlib_buffer_t * b, u16 * next,
2906 vlib_node_runtime_t * error_node)
2912 tcp = tcp_buffer_hdr (b);
2913 flags = tcp->flags & filter_flags;
2914 *next = tm->dispatch_table[tc->state][flags].next;
2915 error = tm->dispatch_table[tc->state][flags].error;
2918 /* Track connection state when packet was received. It is required
2919 * for @ref tcp46_listen_inline to detect whether we reached
2920 * the node as a result of a SYN packet received while in time-wait
2921 * state. In this case the connection_index in vnet buffer will point
2922 * to the existing tcp connection and not the listener
2924 vnet_buffer (b)->tcp.flags = tc->state;
2926 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2928 b->error = error_node->errors[error];
2929 if (error == TCP_ERROR_DISPATCH)
2930 clib_warning ("tcp conn %u disp error state %U flags %U",
2931 tc->c_c_index, format_tcp_state, tc->state,
2932 format_tcp_flags, (int) flags);
2937 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2938 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2940 u32 n_left_from, *from, thread_index = vm->thread_index;
2941 tcp_main_t *tm = vnet_get_tcp_main ();
2942 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2943 u16 nexts[VLIB_FRAME_SIZE], *next;
2945 tcp_update_time_now (tcp_get_worker (thread_index));
2947 from = vlib_frame_vector_args (frame);
2948 n_left_from = frame->n_vectors;
2949 vlib_get_buffers (vm, from, bufs, n_left_from);
2954 while (n_left_from >= 4)
2956 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2957 tcp_connection_t *tc0, *tc1;
2960 vlib_prefetch_buffer_header (b[2], STORE);
2961 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2963 vlib_prefetch_buffer_header (b[3], STORE);
2964 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2967 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2969 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2971 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2974 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2976 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2977 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2979 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2980 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2982 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2983 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2987 if (PREDICT_TRUE (tc0 != 0))
2989 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2990 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2991 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2995 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2996 b[0]->error = node->errors[error0];
2999 if (PREDICT_TRUE (tc1 != 0))
3001 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3002 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3003 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
3007 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3008 b[1]->error = node->errors[error1];
3016 while (n_left_from > 0)
3018 tcp_connection_t *tc0;
3019 u32 error0 = TCP_ERROR_NO_LISTENER;
3021 if (n_left_from > 1)
3023 vlib_prefetch_buffer_header (b[1], STORE);
3024 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3027 next[0] = TCP_INPUT_NEXT_DROP;
3028 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3030 if (PREDICT_TRUE (tc0 != 0))
3032 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3033 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3034 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
3038 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3039 b[0]->error = node->errors[error0];
3047 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3048 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3050 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3051 return frame->n_vectors;
3054 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3055 vlib_node_runtime_t * node,
3056 vlib_frame_t * from_frame)
3058 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3059 1 /* is_nolookup */ );
3062 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3063 vlib_node_runtime_t * node,
3064 vlib_frame_t * from_frame)
3066 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3067 1 /* is_nolookup */ );
3071 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3073 .name = "tcp4-input-nolookup",
3074 /* Takes a vector of packets. */
3075 .vector_size = sizeof (u32),
3076 .n_errors = TCP_N_ERROR,
3077 .error_counters = tcp_input_error_counters,
3078 .n_next_nodes = TCP_INPUT_N_NEXT,
3081 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3082 foreach_tcp4_input_next
3085 .format_buffer = format_tcp_header,
3086 .format_trace = format_tcp_rx_trace,
3091 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3093 .name = "tcp6-input-nolookup",
3094 /* Takes a vector of packets. */
3095 .vector_size = sizeof (u32),
3096 .n_errors = TCP_N_ERROR,
3097 .error_counters = tcp_input_error_counters,
3098 .n_next_nodes = TCP_INPUT_N_NEXT,
3101 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3102 foreach_tcp6_input_next
3105 .format_buffer = format_tcp_header,
3106 .format_trace = format_tcp_rx_trace,
3110 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3111 vlib_frame_t * from_frame)
3113 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3114 0 /* is_nolookup */ );
3117 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3118 vlib_frame_t * from_frame)
3120 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3121 0 /* is_nolookup */ );
3125 VLIB_REGISTER_NODE (tcp4_input_node) =
3127 .name = "tcp4-input",
3128 /* Takes a vector of packets. */
3129 .vector_size = sizeof (u32),
3130 .n_errors = TCP_N_ERROR,
3131 .error_counters = tcp_input_error_counters,
3132 .n_next_nodes = TCP_INPUT_N_NEXT,
3135 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3136 foreach_tcp4_input_next
3139 .format_buffer = format_tcp_header,
3140 .format_trace = format_tcp_rx_trace,
3145 VLIB_REGISTER_NODE (tcp6_input_node) =
3147 .name = "tcp6-input",
3148 /* Takes a vector of packets. */
3149 .vector_size = sizeof (u32),
3150 .n_errors = TCP_N_ERROR,
3151 .error_counters = tcp_input_error_counters,
3152 .n_next_nodes = TCP_INPUT_N_NEXT,
3155 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3156 foreach_tcp6_input_next
3159 .format_buffer = format_tcp_header,
3160 .format_trace = format_tcp_rx_trace,
3164 #ifndef CLIB_MARCH_VARIANT
3166 tcp_check_gso (tcp_connection_t *tc)
3168 tcp_check_tx_offload (tc, tc->c_is_ip4);
3172 tcp_dispatch_table_init (tcp_main_t * tm)
3175 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3176 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3178 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3179 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3182 #define _(t,f,n,e) \
3184 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3185 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3188 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3189 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3190 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3191 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3192 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3193 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3194 TCP_ERROR_ACK_INVALID);
3195 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3196 TCP_ERROR_SEGMENT_INVALID);
3197 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3198 TCP_ERROR_SEGMENT_INVALID);
3199 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3200 TCP_ERROR_INVALID_CONNECTION);
3201 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3202 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3203 TCP_ERROR_SEGMENT_INVALID);
3204 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3205 TCP_ERROR_SEGMENT_INVALID);
3206 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3207 TCP_ERROR_SEGMENT_INVALID);
3208 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3209 TCP_ERROR_SEGMENT_INVALID);
3210 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3211 TCP_ERROR_SEGMENT_INVALID);
3212 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3213 TCP_ERROR_SEGMENT_INVALID);
3214 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3215 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3216 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3217 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3218 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3221 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3222 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3226 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3227 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3229 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3231 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3233 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3234 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3235 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3237 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3238 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3239 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3240 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3241 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3242 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3243 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3244 /* SYN-ACK for a SYN */
3245 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3247 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3248 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3249 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3251 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3252 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3254 /* ACK for for established connection -> tcp-established. */
3255 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3256 /* FIN for for established connection -> tcp-established. */
3257 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3258 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3260 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3262 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3263 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3264 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3266 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3267 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3268 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3269 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3270 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3271 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3272 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3273 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3275 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3276 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3278 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3280 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3281 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3282 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3283 /* ACK or FIN-ACK to our FIN */
3284 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3285 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3287 /* FIN in reply to our FIN from the other side */
3288 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3289 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3290 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3292 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3293 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3294 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3295 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3296 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3297 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3298 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3300 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3301 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3302 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3303 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3305 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3307 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3308 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3309 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3310 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3312 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3313 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3314 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3315 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3317 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3319 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3320 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3321 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3322 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3324 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3325 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3327 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3329 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3330 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3331 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3333 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3334 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3335 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3336 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3337 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3338 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3339 /* FIN confirming that the peer (app) has closed */
3340 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3341 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3342 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3344 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3345 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3347 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3348 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3349 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3351 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3352 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3354 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3355 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3356 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3357 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3358 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3360 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3362 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3363 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3364 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3366 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3367 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3368 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3369 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3370 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3371 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3372 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3373 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3375 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3376 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3378 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3380 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3381 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3382 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3383 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3384 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3386 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3387 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3389 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3390 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3391 * incoming segment not containing a RST causes a RST to be sent in
3393 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3394 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3395 TCP_ERROR_CONNECTION_CLOSED);
3396 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3397 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3398 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3399 TCP_ERROR_CONNECTION_CLOSED);
3403 static clib_error_t *
3404 tcp_input_init (vlib_main_t * vm)
3406 clib_error_t *error = 0;
3407 tcp_main_t *tm = vnet_get_tcp_main ();
3409 if ((error = vlib_call_init_function (vm, tcp_init)))
3412 /* Initialize dispatch table. */
3413 tcp_dispatch_table_init (tm);
3418 VLIB_INIT_FUNCTION (tcp_input_init);
3420 #endif /* CLIB_MARCH_VARIANT */
3423 * fd.io coding-style-patch-verification: ON
3426 * eval: (c-set-style "gnu")