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 += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
870 - tc->sack_sb.last_bytes_delivered;
876 tc->rcv_dupacks += 1;
877 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
879 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
882 tc->prr_delivered += clib_min (tc->snd_mss,
883 tc->snd_nxt - tc->snd_una);
885 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
889 /* If partial ack, assume that the first un-acked segment was lost */
890 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
891 tcp_fastrecovery_first_on (tc);
895 * See if we can exit and stop retransmitting
897 if (seq_geq (tc->snd_una, tc->snd_congestion))
899 /* If spurious return, we've already updated everything */
900 if (tcp_cc_recover (tc))
902 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
906 /* Treat as congestion avoidance ack */
907 tcp_cc_rcv_ack (tc, rs);
911 tcp_program_retransmit (tc);
914 * Notify cc of the event
917 if (!tc->bytes_acked)
919 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
923 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
924 * reset dupacks to 0. Also needed if in congestion recovery */
927 if (tcp_in_recovery (tc))
928 tcp_cc_rcv_ack (tc, rs);
930 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
934 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
936 if (!tcp_in_cong_recovery (tc))
939 if (tcp_opts_sack_permitted (&tc->rcv_opts))
940 tcp_rcv_sacks (tc, tc->snd_una);
944 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
945 tcp_bt_sample_delivery_rate (tc, rs);
947 tcp_cc_handle_event (tc, rs, 1);
951 * Check if duplicate ack as per RFC5681 Sec. 2
954 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
957 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
958 && seq_gt (tc->snd_nxt, tc->snd_una)
959 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
960 && (prev_snd_wnd == tc->snd_wnd));
964 * Checks if ack is a congestion control event.
967 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
968 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
970 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
971 * defined to be 'duplicate' as well */
972 *is_dack = tc->sack_sb.last_sacked_bytes
973 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
975 return (*is_dack || tcp_in_cong_recovery (tc));
979 * Process incoming ACK
982 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
983 tcp_header_t * th, u32 * error)
985 u32 prev_snd_wnd, prev_snd_una;
986 tcp_rate_sample_t rs = { 0 };
989 TCP_EVT (TCP_EVT_CC_STAT, tc);
991 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
992 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
994 /* We've probably entered recovery and the peer still has some
995 * of the data we've sent. Update snd_nxt and accept the ack */
996 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
997 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
999 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1003 tc->errors.above_ack_wnd += 1;
1004 *error = TCP_ERROR_ACK_FUTURE;
1005 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1009 /* If old ACK, probably it's an old dupack */
1010 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1012 tc->errors.below_ack_wnd += 1;
1013 *error = TCP_ERROR_ACK_OLD;
1014 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1016 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1019 tcp_handle_old_ack (tc, &rs);
1021 /* Don't drop yet */
1028 * Looks okay, process feedback
1031 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1032 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1034 prev_snd_wnd = tc->snd_wnd;
1035 prev_snd_una = tc->snd_una;
1036 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1037 vnet_buffer (b)->tcp.ack_number,
1038 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1039 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1040 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1041 tcp_validate_txf_size (tc, tc->bytes_acked);
1043 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1044 tcp_bt_sample_delivery_rate (tc, &rs);
1046 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1048 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1049 if (tc->bytes_acked)
1050 tcp_program_dequeue (wrk, tc);
1053 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1056 * Check if we have congestion event
1059 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1061 tcp_cc_handle_event (tc, &rs, is_dack);
1062 tc->dupacks_in += is_dack;
1063 if (!tcp_in_cong_recovery (tc))
1065 *error = TCP_ERROR_ACK_OK;
1068 *error = TCP_ERROR_ACK_DUP;
1069 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1075 * Update congestion control (slow start/congestion avoidance)
1077 tcp_cc_update (tc, &rs);
1078 *error = TCP_ERROR_ACK_OK;
1083 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1085 if (!tcp_disconnect_pending (tc))
1087 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1088 tcp_disconnect_pending_on (tc);
1093 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1095 u32 thread_index, *pending_disconnects, *pending_resets;
1096 tcp_connection_t *tc;
1099 if (vec_len (wrk->pending_disconnects))
1101 thread_index = wrk->vm->thread_index;
1102 pending_disconnects = wrk->pending_disconnects;
1103 for (i = 0; i < vec_len (pending_disconnects); i++)
1105 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1106 tcp_disconnect_pending_off (tc);
1107 session_transport_closing_notify (&tc->connection);
1109 _vec_len (wrk->pending_disconnects) = 0;
1112 if (vec_len (wrk->pending_resets))
1114 thread_index = wrk->vm->thread_index;
1115 pending_resets = wrk->pending_resets;
1116 for (i = 0; i < vec_len (pending_resets); i++)
1118 tc = tcp_connection_get (pending_resets[i], thread_index);
1119 tcp_disconnect_pending_off (tc);
1120 tcp_handle_rst (tc);
1122 _vec_len (wrk->pending_resets) = 0;
1127 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1130 /* Reject out-of-order fins */
1131 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1134 /* Account for the FIN and send ack */
1136 tc->flags |= TCP_CONN_FINRCVD;
1137 tcp_program_ack (tc);
1138 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1139 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1140 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1141 tcp_program_disconnect (wrk, tc);
1142 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1143 tcp_cfg.closewait_time);
1144 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1145 *error = TCP_ERROR_FIN_RCVD;
1148 /** Enqueue data for delivery to application */
1150 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1153 int written, error = TCP_ERROR_ENQUEUED;
1155 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1157 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1158 1 /* queue event */ , 1);
1159 tc->bytes_in += written;
1161 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1163 /* Update rcv_nxt */
1164 if (PREDICT_TRUE (written == data_len))
1166 tc->rcv_nxt += written;
1168 /* If more data written than expected, account for out-of-order bytes. */
1169 else if (written > data_len)
1171 tc->rcv_nxt += written;
1172 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1174 else if (written > 0)
1176 /* We've written something but FIFO is probably full now */
1177 tc->rcv_nxt += written;
1178 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1182 /* Packet made it through for ack processing */
1183 if (tc->rcv_wnd < tc->snd_mss)
1184 return TCP_ERROR_ZERO_RWND;
1186 return TCP_ERROR_FIFO_FULL;
1189 /* Update SACK list if need be */
1190 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
1192 /* Remove SACK blocks that have been delivered */
1193 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1199 /** Enqueue out-of-order data */
1201 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1207 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1210 /* Enqueue out-of-order data with relative offset */
1211 rv = session_enqueue_stream_connection (&tc->connection, b,
1212 vnet_buffer (b)->tcp.seq_number -
1213 tc->rcv_nxt, 0 /* queue event */ ,
1216 /* Nothing written */
1219 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1220 return TCP_ERROR_FIFO_FULL;
1223 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1224 tc->bytes_in += data_len;
1226 /* Update SACK list if in use */
1227 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1229 ooo_segment_t *newest;
1232 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1234 /* Get the newest segment from the fifo */
1235 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1238 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1239 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1240 start = tc->rcv_nxt + offset;
1241 end = start + ooo_segment_length (s0->rx_fifo, newest);
1242 tcp_update_sack_list (tc, start, end);
1243 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1244 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1248 return TCP_ERROR_ENQUEUED_OOO;
1252 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1254 u32 discard, first = b->current_length;
1255 vlib_main_t *vm = vlib_get_main ();
1257 /* Handle multi-buffer segments */
1258 if (n_bytes_to_drop > b->current_length)
1260 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1264 discard = clib_min (n_bytes_to_drop, b->current_length);
1265 vlib_buffer_advance (b, discard);
1266 b = vlib_get_buffer (vm, b->next_buffer);
1267 n_bytes_to_drop -= discard;
1269 while (n_bytes_to_drop);
1270 if (n_bytes_to_drop > first)
1271 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1274 vlib_buffer_advance (b, n_bytes_to_drop);
1275 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1280 * Receive buffer for connection and handle acks
1282 * It handles both in order or out-of-order data.
1285 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1288 u32 error, n_bytes_to_drop, n_data_bytes;
1290 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1291 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1292 ASSERT (n_data_bytes);
1293 tc->data_segs_in += 1;
1295 /* Make sure we don't consume trailing bytes */
1296 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1297 b->current_length = n_data_bytes;
1299 /* Handle out-of-order data */
1300 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1302 /* Old sequence numbers allowed through because they overlapped
1304 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1306 /* Completely in the past (possible retransmit). Ack
1307 * retransmissions since we may not have any data to send */
1308 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1310 tcp_program_dupack (tc);
1311 tc->errors.below_data_wnd++;
1312 error = TCP_ERROR_SEGMENT_OLD;
1316 /* Chop off the bytes in the past and see if what is left
1317 * can be enqueued in order */
1318 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1319 n_data_bytes -= n_bytes_to_drop;
1320 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1321 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1323 error = TCP_ERROR_SEGMENT_OLD;
1329 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1330 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1331 tcp_program_dupack (tc);
1332 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1333 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1334 tc->rcv_las + tc->rcv_wnd);
1340 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1341 * segments can be enqueued after fifo tail offset changes. */
1342 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1343 tcp_program_ack (tc);
1351 tcp_header_t tcp_header;
1352 tcp_connection_t tcp_connection;
1356 format_tcp_rx_trace (u8 * s, va_list * args)
1358 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1359 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1360 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1361 tcp_connection_t *tc = &t->tcp_connection;
1362 u32 indent = format_get_indent (s);
1364 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1365 format_tcp_state, tc->state, format_white_space, indent,
1366 format_tcp_header, &t->tcp_header, 128);
1372 format_tcp_rx_trace_short (u8 * s, va_list * args)
1374 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1375 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1376 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1378 s = format (s, "%d -> %d (%U)",
1379 clib_net_to_host_u16 (t->tcp_header.dst_port),
1380 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1381 t->tcp_connection.state);
1387 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1388 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1392 clib_memcpy_fast (&t0->tcp_connection, tc0,
1393 sizeof (t0->tcp_connection));
1397 th0 = tcp_buffer_hdr (b0);
1399 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1403 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1404 vlib_frame_t * frame, u8 is_ip4)
1408 n_left = frame->n_vectors;
1409 from = vlib_frame_vector_args (frame);
1413 tcp_connection_t *tc0;
1420 b0 = vlib_get_buffer (vm, bi0);
1422 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1424 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1425 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1427 th0 = tcp_buffer_hdr (b0);
1428 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1437 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1438 u8 is_ip4, u32 evt, u32 val)
1441 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1443 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1446 #define tcp_maybe_inc_counter(node_id, err, count) \
1448 if (next0 != tcp_next_drop (is_ip4)) \
1449 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1450 tcp6_##node_id##_node.index, is_ip4, err, \
1453 #define tcp_inc_counter(node_id, err, count) \
1454 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1455 tcp6_##node_id##_node.index, is_ip4, \
1457 #define tcp_maybe_inc_err_counter(cnts, err) \
1459 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1461 #define tcp_inc_err_counter(cnts, err, val) \
1465 #define tcp_store_err_counters(node_id, cnts) \
1468 for (i = 0; i < TCP_N_ERROR; i++) \
1470 tcp_inc_counter(node_id, i, cnts[i]); \
1475 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1476 vlib_frame_t * frame, int is_ip4)
1478 u32 thread_index = vm->thread_index, errors = 0;
1479 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1480 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1481 u16 err_counters[TCP_N_ERROR] = { 0 };
1482 u32 n_left_from, *from;
1484 if (node->flags & VLIB_NODE_FLAG_TRACE)
1485 tcp_established_trace_frame (vm, node, frame, is_ip4);
1487 from = vlib_frame_vector_args (frame);
1488 n_left_from = frame->n_vectors;
1490 vlib_get_buffers (vm, from, bufs, n_left_from);
1493 while (n_left_from > 0)
1495 u32 error = TCP_ERROR_ACK_OK;
1496 tcp_connection_t *tc;
1499 if (n_left_from > 1)
1501 vlib_prefetch_buffer_header (b[1], LOAD);
1502 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1505 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1508 if (PREDICT_FALSE (tc == 0))
1510 error = TCP_ERROR_INVALID_CONNECTION;
1514 th = tcp_buffer_hdr (b[0]);
1516 /* TODO header prediction fast path */
1518 /* 1-4: check SEQ, RST, SYN */
1519 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1521 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1525 /* 5: check the ACK field */
1526 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1529 /* 6: check the URG bit TODO */
1531 /* 7: process the segment text */
1532 if (vnet_buffer (b[0])->tcp.data_len)
1533 error = tcp_segment_rcv (wrk, tc, b[0]);
1535 /* 8: check the FIN bit */
1536 if (PREDICT_FALSE (tcp_is_fin (th)))
1537 tcp_rcv_fin (wrk, tc, b[0], &error);
1540 tcp_inc_err_counter (err_counters, error, 1);
1546 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1548 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1549 tcp_store_err_counters (established, err_counters);
1550 tcp_handle_postponed_dequeues (wrk);
1551 tcp_handle_disconnects (wrk);
1552 vlib_buffer_free (vm, from, frame->n_vectors);
1554 return frame->n_vectors;
1557 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1558 vlib_node_runtime_t * node,
1559 vlib_frame_t * from_frame)
1561 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1564 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1565 vlib_node_runtime_t * node,
1566 vlib_frame_t * from_frame)
1568 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1572 VLIB_REGISTER_NODE (tcp4_established_node) =
1574 .name = "tcp4-established",
1575 /* Takes a vector of packets. */
1576 .vector_size = sizeof (u32),
1577 .n_errors = TCP_N_ERROR,
1578 .error_counters = tcp_input_error_counters,
1579 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1582 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1583 foreach_tcp_state_next
1586 .format_trace = format_tcp_rx_trace_short,
1591 VLIB_REGISTER_NODE (tcp6_established_node) =
1593 .name = "tcp6-established",
1594 /* Takes a vector of packets. */
1595 .vector_size = sizeof (u32),
1596 .n_errors = TCP_N_ERROR,
1597 .error_counters = tcp_input_error_counters,
1598 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1601 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1602 foreach_tcp_state_next
1605 .format_trace = format_tcp_rx_trace_short,
1611 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1614 transport_connection_t *tmp = 0;
1621 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1624 u8 is_ip_valid = 0, val_l, val_r;
1626 if (tc->connection.is_ip4)
1628 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1630 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1631 &tc->connection.lcl_ip.ip4);
1632 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1633 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1634 &tc->connection.rmt_ip.ip4);
1635 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1636 is_ip_valid = val_l && val_r;
1640 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1642 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1643 &tc->connection.lcl_ip.ip6);
1644 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1645 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1646 &tc->connection.rmt_ip.ip6);
1647 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1648 is_ip_valid = val_l && val_r;
1651 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1652 && (tc->state == TCP_STATE_LISTEN
1653 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1657 handle = session_lookup_half_open_handle (&tc->connection);
1658 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1659 tc->c_proto, tc->c_is_ip4);
1663 if (tmp->lcl_port == hdr->dst_port
1664 && tmp->rmt_port == hdr->src_port)
1666 TCP_DBG ("half-open is valid!");
1675 * Lookup transport connection
1677 static tcp_connection_t *
1678 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1682 transport_connection_t *tconn;
1683 tcp_connection_t *tc;
1688 ip4 = vlib_buffer_get_current (b);
1689 tcp = ip4_next_header (ip4);
1690 tconn = session_lookup_connection_wt4 (fib_index,
1695 TRANSPORT_PROTO_TCP,
1696 thread_index, &is_filtered);
1697 tc = tcp_get_connection_from_transport (tconn);
1698 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1703 ip6 = vlib_buffer_get_current (b);
1704 tcp = ip6_next_header (ip6);
1705 tconn = session_lookup_connection_wt6 (fib_index,
1710 TRANSPORT_PROTO_TCP,
1711 thread_index, &is_filtered);
1712 tc = tcp_get_connection_from_transport (tconn);
1713 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1718 static tcp_connection_t *
1719 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1725 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1726 tcp_header_t *tcp = tcp_buffer_hdr (b);
1727 s = session_lookup_listener4 (fib_index,
1729 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1733 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1734 tcp_header_t *tcp = tcp_buffer_hdr (b);
1735 s = session_lookup_listener6 (fib_index,
1737 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1740 if (PREDICT_TRUE (s != 0))
1741 return tcp_get_connection_from_transport (transport_get_listener
1742 (TRANSPORT_PROTO_TCP,
1743 s->connection_index));
1749 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1750 u32 *from, u32 n_bufs)
1752 tcp_connection_t *tc = 0;
1757 for (i = 0; i < n_bufs; i++)
1759 b = vlib_get_buffer (vm, from[i]);
1760 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1763 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1764 t = vlib_add_trace (vm, node, b, sizeof (*t));
1765 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1770 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1772 vnet_main_t *vnm = vnet_get_main ();
1773 const dpo_id_t *dpo;
1774 const load_balance_t *lb;
1775 vnet_hw_interface_t *hw_if;
1776 u32 sw_if_idx, lb_idx;
1780 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1781 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1785 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1786 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1789 lb = load_balance_get (lb_idx);
1790 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1792 dpo = load_balance_get_bucket_i (lb, 0);
1794 sw_if_idx = dpo_get_urpf (dpo);
1795 if (PREDICT_FALSE (sw_if_idx == ~0))
1798 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1799 if (hw_if->caps & VNET_HW_INTERFACE_CAP_SUPPORTS_TCP_GSO)
1800 tc->cfg_flags |= TCP_CFG_F_TSO;
1804 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1805 vlib_frame_t *frame, int is_ip4)
1807 u32 n_left_from, *from, thread_index = vm->thread_index, errors = 0;
1808 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1809 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1811 from = vlib_frame_vector_args (frame);
1812 n_left_from = frame->n_vectors;
1814 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1815 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1817 vlib_get_buffers (vm, from, bufs, n_left_from);
1820 while (n_left_from > 0)
1822 u32 ack, seq, error = TCP_ERROR_NONE;
1823 tcp_connection_t *tc, *new_tc;
1826 tc = tcp_half_open_connection_get (
1827 vnet_buffer (b[0])->tcp.connection_index);
1828 if (PREDICT_FALSE (tc == 0))
1830 error = TCP_ERROR_INVALID_CONNECTION;
1834 /* Half-open completed or cancelled recently but the connection
1835 * was't removed yet by the owning thread */
1836 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1838 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1842 ack = vnet_buffer (b[0])->tcp.ack_number;
1843 seq = vnet_buffer (b[0])->tcp.seq_number;
1844 tcp = tcp_buffer_hdr (b[0]);
1846 /* Crude check to see if the connection handle does not match
1847 * the packet. Probably connection just switched to established */
1848 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1849 tcp->src_port != tc->c_rmt_port))
1851 error = TCP_ERROR_INVALID_CONNECTION;
1855 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1857 error = TCP_ERROR_SEGMENT_INVALID;
1861 /* SYNs consume sequence numbers */
1862 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1865 * 1. check the ACK bit
1869 * If the ACK bit is set
1870 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1871 * the RST bit is set, if so drop the segment and return)
1872 * <SEQ=SEG.ACK><CTL=RST>
1873 * and discard the segment. Return.
1874 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1878 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1881 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1882 error = TCP_ERROR_RCV_WND;
1886 /* Make sure ACK is valid */
1887 if (seq_gt (tc->snd_una, ack))
1889 error = TCP_ERROR_ACK_INVALID;
1895 * 2. check the RST bit
1900 /* If ACK is acceptable, signal client that peer is not
1901 * willing to accept connection and drop connection*/
1903 tcp_rcv_rst (wrk, tc);
1904 error = TCP_ERROR_RST_RCVD;
1909 * 3. check the security and precedence (skipped)
1913 * 4. check the SYN bit
1916 /* No SYN flag. Drop. */
1919 error = TCP_ERROR_SEGMENT_INVALID;
1924 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1926 error = TCP_ERROR_OPTIONS;
1930 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1931 * current thread pool. */
1932 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1933 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1935 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1937 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1939 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1940 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1943 if (tcp_opts_wscale (&new_tc->rcv_opts))
1944 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1946 new_tc->rcv_wscale = 0;
1948 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1949 << new_tc->snd_wscale;
1950 new_tc->snd_wl1 = seq;
1951 new_tc->snd_wl2 = ack;
1953 tcp_connection_init_vars (new_tc);
1955 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1956 if (PREDICT_TRUE (tcp_ack (tcp)))
1958 /* Our SYN is ACKed: we have iss < ack = snd_una */
1960 /* TODO Dequeue acknowledged segments if we support Fast Open */
1961 new_tc->snd_una = ack;
1962 new_tc->state = TCP_STATE_ESTABLISHED;
1964 /* Make sure las is initialized for the wnd computation */
1965 new_tc->rcv_las = new_tc->rcv_nxt;
1967 /* Notify app that we have connection. If session layer can't
1968 * allocate session send reset */
1969 if (session_stream_connect_notify (&new_tc->connection,
1972 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1973 tcp_connection_cleanup (new_tc);
1974 error = TCP_ERROR_CREATE_SESSION_FAIL;
1978 transport_fifos_init_ooo (&new_tc->connection);
1979 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1980 /* Update rtt with the syn-ack sample */
1981 tcp_estimate_initial_rtt (new_tc);
1982 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1983 error = TCP_ERROR_SYN_ACKS_RCVD;
1985 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1988 new_tc->state = TCP_STATE_SYN_RCVD;
1990 /* Notify app that we have connection */
1991 if (session_stream_connect_notify (&new_tc->connection,
1994 tcp_connection_cleanup (new_tc);
1995 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1996 TCP_EVT (TCP_EVT_RST_SENT, tc);
1997 error = TCP_ERROR_CREATE_SESSION_FAIL;
2001 transport_fifos_init_ooo (&new_tc->connection);
2002 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
2004 tcp_init_snd_vars (new_tc);
2005 tcp_send_synack (new_tc);
2006 error = TCP_ERROR_SYNS_RCVD;
2010 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
2011 tcp_check_tx_offload (new_tc, is_ip4);
2013 /* Read data, if any */
2014 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
2016 clib_warning ("rcvd data in syn-sent");
2017 error = tcp_segment_rcv (wrk, new_tc, b[0]);
2018 if (error == TCP_ERROR_ACK_OK)
2019 error = TCP_ERROR_SYN_ACKS_RCVD;
2023 /* Send ack now instead of programming it because connection was
2024 * just established and it's not optional. */
2025 tcp_send_ack (new_tc);
2030 /* If this is not the owning thread, wait for syn retransmit to
2031 * expire and cleanup then */
2032 if (tcp_half_open_connection_cleanup (tc))
2033 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
2039 tcp_inc_counter (syn_sent, error, 1);
2043 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2044 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2045 vlib_buffer_free (vm, from, frame->n_vectors);
2046 tcp_handle_disconnects (wrk);
2048 return frame->n_vectors;
2051 VLIB_NODE_FN (tcp4_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, 1 /* is_ip4 */ );
2058 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2059 vlib_node_runtime_t * node,
2060 vlib_frame_t * from_frame)
2062 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2066 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2068 .name = "tcp4-syn-sent",
2069 /* Takes a vector of packets. */
2070 .vector_size = sizeof (u32),
2071 .n_errors = TCP_N_ERROR,
2072 .error_counters = tcp_input_error_counters,
2073 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2076 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2077 foreach_tcp_state_next
2080 .format_trace = format_tcp_rx_trace_short,
2085 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2087 .name = "tcp6-syn-sent",
2088 /* Takes a vector of packets. */
2089 .vector_size = sizeof (u32),
2090 .n_errors = TCP_N_ERROR,
2091 .error_counters = tcp_input_error_counters,
2092 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2095 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2096 foreach_tcp_state_next
2099 .format_trace = format_tcp_rx_trace_short,
2104 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2105 u32 *from, u32 n_bufs)
2107 u32 thread_index = vm->thread_index;
2108 tcp_connection_t *tc = 0;
2113 for (i = 0; i < n_bufs; i++)
2115 b = vlib_get_buffer (vm, from[i]);
2116 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2118 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2120 t = vlib_add_trace (vm, node, b, sizeof (*t));
2121 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2126 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2127 * as per RFC793 p. 64
2130 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2131 vlib_frame_t *frame, int is_ip4)
2133 u32 thread_index = vm->thread_index, errors, n_left_from, *from, max_deq;
2134 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2135 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2137 from = vlib_frame_vector_args (frame);
2138 n_left_from = frame->n_vectors;
2140 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2141 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2143 vlib_get_buffers (vm, from, bufs, n_left_from);
2146 while (n_left_from > 0)
2148 u32 error = TCP_ERROR_NONE;
2149 tcp_header_t *tcp = 0;
2150 tcp_connection_t *tc;
2153 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2155 if (PREDICT_FALSE (tc == 0))
2157 error = TCP_ERROR_INVALID_CONNECTION;
2161 tcp = tcp_buffer_hdr (b[0]);
2162 is_fin = tcp_is_fin (tcp);
2166 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2168 tcp_connection_t *tmp;
2169 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2171 if (tmp->state != tc->state)
2173 if (tc->state != TCP_STATE_CLOSED)
2174 clib_warning ("state changed");
2181 * Special treatment for CLOSED
2183 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2185 error = TCP_ERROR_CONNECTION_CLOSED;
2190 * For all other states (except LISTEN)
2193 /* 1-4: check SEQ, RST, SYN */
2194 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2197 /* 5: check the ACK field */
2200 case TCP_STATE_SYN_RCVD:
2202 /* Make sure the segment is exactly right */
2203 if (tc->rcv_nxt != vnet_buffer (b[0])->tcp.seq_number || is_fin)
2205 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2206 error = TCP_ERROR_SEGMENT_INVALID;
2211 * If the segment acknowledgment is not acceptable, form a
2213 * <SEQ=SEG.ACK><CTL=RST>
2216 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2218 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2219 error = TCP_ERROR_SEGMENT_INVALID;
2223 /* Update rtt and rto */
2224 tcp_estimate_initial_rtt (tc);
2225 tcp_connection_tx_pacer_update (tc);
2227 /* Switch state to ESTABLISHED */
2228 tc->state = TCP_STATE_ESTABLISHED;
2229 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2231 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2232 tcp_check_tx_offload (tc, is_ip4);
2234 /* Initialize session variables */
2235 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2236 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2237 << tc->rcv_opts.wscale;
2238 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2239 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2241 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2242 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2243 if (session_stream_accept_notify (&tc->connection))
2245 error = TCP_ERROR_MSG_QUEUE_FULL;
2246 tcp_send_reset (tc);
2247 session_transport_delete_notify (&tc->connection);
2248 tcp_connection_cleanup (tc);
2251 error = TCP_ERROR_ACK_OK;
2253 case TCP_STATE_ESTABLISHED:
2254 /* We can get packets in established state here because they
2255 * were enqueued before state change */
2256 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2260 case TCP_STATE_FIN_WAIT_1:
2261 /* In addition to the processing for the ESTABLISHED state, if
2262 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2263 * continue processing in that state. */
2264 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2267 /* Still have to send the FIN */
2268 if (tc->flags & TCP_CONN_FINPNDG)
2270 /* TX fifo finally drained */
2271 max_deq = transport_max_tx_dequeue (&tc->connection);
2272 if (max_deq <= tc->burst_acked)
2274 /* If a fin was received and data was acked extend wait */
2275 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2276 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2277 tcp_cfg.closewait_time);
2279 /* If FIN is ACKed */
2280 else if (tc->snd_una == tc->snd_nxt)
2282 /* Stop all retransmit timers because we have nothing more
2284 tcp_connection_timers_reset (tc);
2286 /* We already have a FIN but didn't transition to CLOSING
2287 * because of outstanding tx data. Close the connection. */
2288 if (tc->flags & TCP_CONN_FINRCVD)
2290 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2291 session_transport_closed_notify (&tc->connection);
2292 tcp_program_cleanup (wrk, tc);
2296 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2297 /* Enable waitclose because we're willing to wait for peer's
2298 * FIN but not indefinitely. */
2299 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2300 tcp_cfg.finwait2_time);
2302 /* Don't try to deq the FIN acked */
2303 if (tc->burst_acked > 1)
2304 session_tx_fifo_dequeue_drop (&tc->connection,
2305 tc->burst_acked - 1);
2306 tc->burst_acked = 0;
2309 case TCP_STATE_FIN_WAIT_2:
2310 /* In addition to the processing for the ESTABLISHED state, if
2311 * the retransmission queue is empty, the user's CLOSE can be
2312 * acknowledged ("ok") but do not delete the TCB. */
2313 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2315 tc->burst_acked = 0;
2317 case TCP_STATE_CLOSE_WAIT:
2318 /* Do the same processing as for the ESTABLISHED state. */
2319 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2322 if (!(tc->flags & TCP_CONN_FINPNDG))
2325 /* Still have outstanding tx data */
2326 max_deq = transport_max_tx_dequeue (&tc->connection);
2327 if (max_deq > tc->burst_acked)
2331 tcp_connection_timers_reset (tc);
2332 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2333 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2334 tcp_cfg.lastack_time);
2336 case TCP_STATE_CLOSING:
2337 /* In addition to the processing for the ESTABLISHED state, if
2338 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2339 * otherwise ignore the segment. */
2340 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2343 if (tc->snd_una != tc->snd_nxt)
2346 tcp_connection_timers_reset (tc);
2347 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2348 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2349 tcp_cfg.timewait_time);
2350 session_transport_closed_notify (&tc->connection);
2354 case TCP_STATE_LAST_ACK:
2355 /* The only thing that [should] arrive in this state is an
2356 * acknowledgment of our FIN. If our FIN is now acknowledged,
2357 * delete the TCB, enter the CLOSED state, and return. */
2359 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2362 /* Apparently our ACK for the peer's FIN was lost */
2363 if (is_fin && tc->snd_una != tc->snd_nxt)
2369 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2370 session_transport_closed_notify (&tc->connection);
2372 /* Don't free the connection from the data path since
2373 * we can't ensure that we have no packets already enqueued
2374 * to output. Rely instead on the waitclose timer */
2375 tcp_connection_timers_reset (tc);
2376 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2381 case TCP_STATE_TIME_WAIT:
2382 /* The only thing that can arrive in this state is a
2383 * retransmission of the remote FIN. Acknowledge it, and restart
2384 * the 2 MSL timeout. */
2386 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2392 tcp_program_ack (tc);
2393 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2394 tcp_cfg.timewait_time);
2402 /* 6: check the URG bit TODO */
2404 /* 7: process the segment text */
2407 case TCP_STATE_ESTABLISHED:
2408 case TCP_STATE_FIN_WAIT_1:
2409 case TCP_STATE_FIN_WAIT_2:
2410 if (vnet_buffer (b[0])->tcp.data_len)
2411 error = tcp_segment_rcv (wrk, tc, b[0]);
2412 /* Don't accept out of order fins lower */
2413 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2416 case TCP_STATE_CLOSE_WAIT:
2417 case TCP_STATE_CLOSING:
2418 case TCP_STATE_LAST_ACK:
2419 case TCP_STATE_TIME_WAIT:
2420 /* This should not occur, since a FIN has been received from the
2421 * remote side. Ignore the segment text. */
2425 /* 8: check the FIN bit */
2429 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2433 case TCP_STATE_ESTABLISHED:
2434 /* Account for the FIN and send ack */
2436 tcp_program_ack (tc);
2437 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2438 tcp_program_disconnect (wrk, tc);
2439 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2440 tcp_cfg.closewait_time);
2442 case TCP_STATE_SYN_RCVD:
2443 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2444 * notified yet, set a cleanup timer instead of relying on
2445 * disconnect notify and the implicit close call. */
2446 tcp_connection_timers_reset (tc);
2449 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2450 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2451 tcp_cfg.lastack_time);
2453 case TCP_STATE_CLOSE_WAIT:
2454 case TCP_STATE_CLOSING:
2455 case TCP_STATE_LAST_ACK:
2458 case TCP_STATE_FIN_WAIT_1:
2461 if (tc->flags & TCP_CONN_FINPNDG)
2463 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2464 * sending it. Since we already received a fin, do not wait
2466 tc->flags |= TCP_CONN_FINRCVD;
2467 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2468 tcp_cfg.closewait_time);
2472 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2473 tcp_program_ack (tc);
2474 /* Wait for ACK for our FIN but not forever */
2475 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2476 tcp_cfg.closing_time);
2479 case TCP_STATE_FIN_WAIT_2:
2480 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2482 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2483 tcp_connection_timers_reset (tc);
2484 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2485 tcp_cfg.timewait_time);
2486 tcp_program_ack (tc);
2487 session_transport_closed_notify (&tc->connection);
2489 case TCP_STATE_TIME_WAIT:
2490 /* Remain in the TIME-WAIT state. Restart the time-wait
2493 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2494 tcp_cfg.timewait_time);
2497 error = TCP_ERROR_FIN_RCVD;
2503 tcp_inc_counter (rcv_process, error, 1);
2506 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2508 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2509 tcp_handle_postponed_dequeues (wrk);
2510 tcp_handle_disconnects (wrk);
2511 vlib_buffer_free (vm, from, frame->n_vectors);
2513 return frame->n_vectors;
2516 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2517 vlib_node_runtime_t * node,
2518 vlib_frame_t * from_frame)
2520 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2523 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2524 vlib_node_runtime_t * node,
2525 vlib_frame_t * from_frame)
2527 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2531 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2533 .name = "tcp4-rcv-process",
2534 /* Takes a vector of packets. */
2535 .vector_size = sizeof (u32),
2536 .n_errors = TCP_N_ERROR,
2537 .error_counters = tcp_input_error_counters,
2538 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2541 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2542 foreach_tcp_state_next
2545 .format_trace = format_tcp_rx_trace_short,
2550 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2552 .name = "tcp6-rcv-process",
2553 /* Takes a vector of packets. */
2554 .vector_size = sizeof (u32),
2555 .n_errors = TCP_N_ERROR,
2556 .error_counters = tcp_input_error_counters,
2557 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2560 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2561 foreach_tcp_state_next
2564 .format_trace = format_tcp_rx_trace_short,
2569 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2570 u32 *to_next, u32 n_bufs)
2572 tcp_connection_t *tc = 0;
2577 for (i = 0; i < n_bufs; i++)
2579 b = vlib_get_buffer (vm, to_next[i]);
2580 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2582 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2583 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2584 t = vlib_add_trace (vm, node, b, sizeof (*t));
2585 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2590 * SYN received in TIME-WAIT state.
2593 * "When a connection is [...] on TIME-WAIT state [...]
2594 * [a TCP] MAY accept a new SYN from the remote TCP to
2595 * reopen the connection directly, if it:
2597 * (1) assigns its initial sequence number for the new
2598 * connection to be larger than the largest sequence
2599 * number it used on the previous connection incarnation,
2602 * (2) returns to TIME-WAIT state if the SYN turns out
2603 * to be an old duplicate".
2605 * The function returns true if the syn can be accepted during
2606 * connection time-wait (port reuse). In this case the function
2607 * also calculates what the iss should be for the new connection.
2610 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2612 int paws_reject = tcp_segment_check_paws (tc);
2616 /* Check that the SYN arrived out of window. We accept it */
2618 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2619 (tcp_opts_tstamp (&tc->rcv_opts) &&
2620 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2622 /* Set the iss of the new connection to be the largest sequence number
2623 * the old peer would have accepted and add some random number
2625 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2626 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2636 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2637 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2638 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2639 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2645 * LISTEN state processing as per RFC 793 p. 65
2648 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2649 vlib_frame_t *frame, int is_ip4)
2651 u32 n_left_from, *from, n_syns = 0;
2652 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2653 u32 thread_index = vm->thread_index;
2656 from = vlib_frame_vector_args (frame);
2657 n_left_from = frame->n_vectors;
2659 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2660 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2662 vlib_get_buffers (vm, from, bufs, n_left_from);
2665 while (n_left_from > 0)
2667 u32 error = TCP_ERROR_NONE;
2668 tcp_connection_t *lc, *child;
2670 /* Flags initialized with connection state after lookup */
2671 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2673 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2675 else /* We are in TimeWait state*/
2677 tcp_connection_t *tc;
2678 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2680 if (tc->state != TCP_STATE_TIME_WAIT)
2682 error = TCP_ERROR_CREATE_EXISTS;
2686 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2688 /* This SYN can't be accepted */
2689 error = TCP_ERROR_CREATE_EXISTS;
2693 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2694 /* clean up the old session */
2695 tcp_connection_del (tc);
2696 /* listener was cleaned up */
2699 error = TCP_ERROR_NO_LISTENER;
2704 /* Make sure connection wasn't just created */
2706 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2707 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2709 error = TCP_ERROR_CREATE_EXISTS;
2713 /* Create child session. For syn-flood protection use filter */
2715 /* 1. first check for an RST: handled by input dispatch */
2717 /* 2. second check for an ACK: handled by input dispatch */
2719 /* 3. check for a SYN (did that already) */
2721 /* Create child session and send SYN-ACK */
2722 child = tcp_connection_alloc (thread_index);
2724 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2726 error = TCP_ERROR_OPTIONS;
2727 tcp_connection_free (child);
2731 tcp_init_w_buffer (child, b[0], is_ip4);
2733 child->state = TCP_STATE_SYN_RCVD;
2734 child->c_fib_index = lc->c_fib_index;
2735 child->cc_algo = lc->cc_algo;
2737 /* In the regular case, the tw_iss will be zero, but
2738 * in the special case of syn arriving in time_wait state, the value
2739 * will be set according to rfc 1122
2741 child->iss = tw_iss;
2742 tcp_connection_init_vars (child);
2743 child->rto = TCP_RTO_MIN;
2746 * This initializes elog track, must be done before synack.
2747 * We also do it before possible tcp_connection_cleanup() as it
2748 * generates TCP_EVT_DELETE event.
2750 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2752 if (session_stream_accept (&child->connection, lc->c_s_index,
2753 lc->c_thread_index, 0 /* notify */ ))
2755 tcp_connection_cleanup (child);
2756 error = TCP_ERROR_CREATE_SESSION_FAIL;
2760 transport_fifos_init_ooo (&child->connection);
2761 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2763 tcp_send_synack (child);
2769 n_syns += (error == TCP_ERROR_NONE);
2772 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2773 vlib_buffer_free (vm, from, frame->n_vectors);
2775 return frame->n_vectors;
2778 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2779 vlib_frame_t * from_frame)
2781 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2784 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2785 vlib_frame_t * from_frame)
2787 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2791 VLIB_REGISTER_NODE (tcp4_listen_node) =
2793 .name = "tcp4-listen",
2794 /* Takes a vector of packets. */
2795 .vector_size = sizeof (u32),
2796 .n_errors = TCP_N_ERROR,
2797 .error_counters = tcp_input_error_counters,
2798 .n_next_nodes = TCP_LISTEN_N_NEXT,
2801 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2802 foreach_tcp_state_next
2805 .format_trace = format_tcp_rx_trace_short,
2810 VLIB_REGISTER_NODE (tcp6_listen_node) =
2812 .name = "tcp6-listen",
2813 /* Takes a vector of packets. */
2814 .vector_size = sizeof (u32),
2815 .n_errors = TCP_N_ERROR,
2816 .error_counters = tcp_input_error_counters,
2817 .n_next_nodes = TCP_LISTEN_N_NEXT,
2820 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2821 foreach_tcp_state_next
2824 .format_trace = format_tcp_rx_trace_short,
2828 typedef enum _tcp_input_next
2830 TCP_INPUT_NEXT_DROP,
2831 TCP_INPUT_NEXT_LISTEN,
2832 TCP_INPUT_NEXT_RCV_PROCESS,
2833 TCP_INPUT_NEXT_SYN_SENT,
2834 TCP_INPUT_NEXT_ESTABLISHED,
2835 TCP_INPUT_NEXT_RESET,
2836 TCP_INPUT_NEXT_PUNT,
2840 #define foreach_tcp4_input_next \
2841 _ (DROP, "ip4-drop") \
2842 _ (LISTEN, "tcp4-listen") \
2843 _ (RCV_PROCESS, "tcp4-rcv-process") \
2844 _ (SYN_SENT, "tcp4-syn-sent") \
2845 _ (ESTABLISHED, "tcp4-established") \
2846 _ (RESET, "tcp4-reset") \
2847 _ (PUNT, "ip4-punt")
2849 #define foreach_tcp6_input_next \
2850 _ (DROP, "ip6-drop") \
2851 _ (LISTEN, "tcp6-listen") \
2852 _ (RCV_PROCESS, "tcp6-rcv-process") \
2853 _ (SYN_SENT, "tcp6-syn-sent") \
2854 _ (ESTABLISHED, "tcp6-established") \
2855 _ (RESET, "tcp6-reset") \
2856 _ (PUNT, "ip6-punt")
2858 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2861 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2862 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2864 tcp_connection_t *tc;
2869 for (i = 0; i < n_bufs; i++)
2871 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2873 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2874 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2876 tcp = vlib_buffer_get_current (bs[i]);
2877 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2883 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2885 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2887 *next = TCP_INPUT_NEXT_DROP;
2889 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2891 *next = TCP_INPUT_NEXT_PUNT;
2892 *error = TCP_ERROR_PUNT;
2896 *next = TCP_INPUT_NEXT_RESET;
2897 *error = TCP_ERROR_NO_LISTENER;
2902 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2903 vlib_buffer_t * b, u16 * next,
2904 vlib_node_runtime_t * error_node)
2910 tcp = tcp_buffer_hdr (b);
2911 flags = tcp->flags & filter_flags;
2912 *next = tm->dispatch_table[tc->state][flags].next;
2913 error = tm->dispatch_table[tc->state][flags].error;
2916 /* Track connection state when packet was received. It is required
2917 * for @ref tcp46_listen_inline to detect whether we reached
2918 * the node as a result of a SYN packet received while in time-wait
2919 * state. In this case the connection_index in vnet buffer will point
2920 * to the existing tcp connection and not the listener
2922 vnet_buffer (b)->tcp.flags = tc->state;
2924 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2926 b->error = error_node->errors[error];
2927 if (error == TCP_ERROR_DISPATCH)
2928 clib_warning ("tcp conn %u disp error state %U flags %U",
2929 tc->c_c_index, format_tcp_state, tc->state,
2930 format_tcp_flags, (int) flags);
2935 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2936 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2938 u32 n_left_from, *from, thread_index = vm->thread_index;
2939 tcp_main_t *tm = vnet_get_tcp_main ();
2940 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2941 u16 nexts[VLIB_FRAME_SIZE], *next;
2943 tcp_update_time_now (tcp_get_worker (thread_index));
2945 from = vlib_frame_vector_args (frame);
2946 n_left_from = frame->n_vectors;
2947 vlib_get_buffers (vm, from, bufs, n_left_from);
2952 while (n_left_from >= 4)
2954 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2955 tcp_connection_t *tc0, *tc1;
2958 vlib_prefetch_buffer_header (b[2], STORE);
2959 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2961 vlib_prefetch_buffer_header (b[3], STORE);
2962 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2965 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2967 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2969 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2972 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2974 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2975 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2977 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2978 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2980 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2981 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2985 if (PREDICT_TRUE (tc0 != 0))
2987 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2988 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2989 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2993 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2994 b[0]->error = node->errors[error0];
2997 if (PREDICT_TRUE (tc1 != 0))
2999 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3000 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3001 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
3005 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3006 b[1]->error = node->errors[error1];
3014 while (n_left_from > 0)
3016 tcp_connection_t *tc0;
3017 u32 error0 = TCP_ERROR_NO_LISTENER;
3019 if (n_left_from > 1)
3021 vlib_prefetch_buffer_header (b[1], STORE);
3022 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3025 next[0] = TCP_INPUT_NEXT_DROP;
3026 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3028 if (PREDICT_TRUE (tc0 != 0))
3030 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3031 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3032 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
3036 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3037 b[0]->error = node->errors[error0];
3045 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3046 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3048 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3049 return frame->n_vectors;
3052 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3053 vlib_node_runtime_t * node,
3054 vlib_frame_t * from_frame)
3056 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3057 1 /* is_nolookup */ );
3060 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3061 vlib_node_runtime_t * node,
3062 vlib_frame_t * from_frame)
3064 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3065 1 /* is_nolookup */ );
3069 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3071 .name = "tcp4-input-nolookup",
3072 /* Takes a vector of packets. */
3073 .vector_size = sizeof (u32),
3074 .n_errors = TCP_N_ERROR,
3075 .error_counters = tcp_input_error_counters,
3076 .n_next_nodes = TCP_INPUT_N_NEXT,
3079 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3080 foreach_tcp4_input_next
3083 .format_buffer = format_tcp_header,
3084 .format_trace = format_tcp_rx_trace,
3089 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3091 .name = "tcp6-input-nolookup",
3092 /* Takes a vector of packets. */
3093 .vector_size = sizeof (u32),
3094 .n_errors = TCP_N_ERROR,
3095 .error_counters = tcp_input_error_counters,
3096 .n_next_nodes = TCP_INPUT_N_NEXT,
3099 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3100 foreach_tcp6_input_next
3103 .format_buffer = format_tcp_header,
3104 .format_trace = format_tcp_rx_trace,
3108 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3109 vlib_frame_t * from_frame)
3111 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3112 0 /* is_nolookup */ );
3115 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3116 vlib_frame_t * from_frame)
3118 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3119 0 /* is_nolookup */ );
3123 VLIB_REGISTER_NODE (tcp4_input_node) =
3125 .name = "tcp4-input",
3126 /* Takes a vector of packets. */
3127 .vector_size = sizeof (u32),
3128 .n_errors = TCP_N_ERROR,
3129 .error_counters = tcp_input_error_counters,
3130 .n_next_nodes = TCP_INPUT_N_NEXT,
3133 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3134 foreach_tcp4_input_next
3137 .format_buffer = format_tcp_header,
3138 .format_trace = format_tcp_rx_trace,
3143 VLIB_REGISTER_NODE (tcp6_input_node) =
3145 .name = "tcp6-input",
3146 /* Takes a vector of packets. */
3147 .vector_size = sizeof (u32),
3148 .n_errors = TCP_N_ERROR,
3149 .error_counters = tcp_input_error_counters,
3150 .n_next_nodes = TCP_INPUT_N_NEXT,
3153 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3154 foreach_tcp6_input_next
3157 .format_buffer = format_tcp_header,
3158 .format_trace = format_tcp_rx_trace,
3162 #ifndef CLIB_MARCH_VARIANT
3164 tcp_check_gso (tcp_connection_t *tc)
3166 tcp_check_tx_offload (tc, tc->c_is_ip4);
3170 tcp_dispatch_table_init (tcp_main_t * tm)
3173 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3174 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3176 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3177 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3180 #define _(t,f,n,e) \
3182 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3183 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3186 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3187 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3188 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3189 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3190 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3191 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3192 TCP_ERROR_ACK_INVALID);
3193 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3194 TCP_ERROR_SEGMENT_INVALID);
3195 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3196 TCP_ERROR_SEGMENT_INVALID);
3197 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3198 TCP_ERROR_INVALID_CONNECTION);
3199 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3200 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3201 TCP_ERROR_SEGMENT_INVALID);
3202 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3203 TCP_ERROR_SEGMENT_INVALID);
3204 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3205 TCP_ERROR_SEGMENT_INVALID);
3206 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3207 TCP_ERROR_SEGMENT_INVALID);
3208 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3209 TCP_ERROR_SEGMENT_INVALID);
3210 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3211 TCP_ERROR_SEGMENT_INVALID);
3212 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3213 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3214 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3215 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3216 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3217 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3219 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3220 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3222 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3225 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3226 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3227 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3229 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3231 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3232 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3233 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3235 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3236 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3237 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3238 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3239 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3240 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3241 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3242 /* SYN-ACK for a SYN */
3243 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3245 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3246 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3247 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3249 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3250 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3252 /* ACK for for established connection -> tcp-established. */
3253 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3254 /* FIN for for established connection -> tcp-established. */
3255 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3256 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3258 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3260 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3261 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3262 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3264 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3265 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3266 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3267 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3268 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3269 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3270 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3271 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3273 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3274 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3276 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3278 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3279 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3280 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3281 /* ACK or FIN-ACK to our FIN */
3282 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3283 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3285 /* FIN in reply to our FIN from the other side */
3286 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3287 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3288 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3290 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3291 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3292 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3293 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3294 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3295 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3296 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3298 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3299 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3300 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3301 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3303 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3305 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3306 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3307 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3308 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3310 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3311 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3312 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3313 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3315 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3317 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3318 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3319 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3320 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3322 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3323 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3325 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3327 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3328 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3329 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3331 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3332 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3333 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3334 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3335 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3336 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3337 /* FIN confirming that the peer (app) has closed */
3338 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3339 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3340 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3342 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3343 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3345 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3346 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3347 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3349 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3350 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3352 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3353 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3354 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3355 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3356 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3358 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3360 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3361 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3362 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3364 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3365 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3366 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3367 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3368 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3369 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3370 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3371 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3373 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3374 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3376 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3378 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3379 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3380 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3381 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3382 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3384 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3385 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3387 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3388 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3389 * incoming segment not containing a RST causes a RST to be sent in
3391 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3392 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3393 TCP_ERROR_CONNECTION_CLOSED);
3394 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3395 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3396 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3397 TCP_ERROR_CONNECTION_CLOSED);
3401 static clib_error_t *
3402 tcp_input_init (vlib_main_t * vm)
3404 clib_error_t *error = 0;
3405 tcp_main_t *tm = vnet_get_tcp_main ();
3407 if ((error = vlib_call_init_function (vm, tcp_init)))
3410 /* Initialize dispatch table. */
3411 tcp_dispatch_table_init (tm);
3416 VLIB_INIT_FUNCTION (tcp_input_init);
3418 #endif /* CLIB_MARCH_VARIANT */
3421 * fd.io coding-style-patch-verification: ON
3424 * eval: (c-set-style "gnu")