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_set_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 if (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
634 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
636 /* Set persist timer if we just got 0 wnd. If already set,
637 * update it because some data sent with snd_wnd < snd_mss was
639 if (tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
640 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
641 tcp_persist_timer_set (&wrk->timer_wheel, tc);
646 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
648 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
649 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
652 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
655 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
665 * Init loss recovery/fast recovery.
667 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
668 * updated in @ref tcp_cc_handle_event after fast retransmit
671 tcp_cc_init_congestion (tcp_connection_t * tc)
673 tcp_fastrecovery_on (tc);
674 tc->snd_congestion = tc->snd_nxt;
675 tc->cwnd_acc_bytes = 0;
676 tc->snd_rxt_bytes = 0;
677 tc->rxt_delivered = 0;
678 tc->prr_delivered = 0;
679 tc->prr_start = tc->snd_una;
680 tc->prev_ssthresh = tc->ssthresh;
681 tc->prev_cwnd = tc->cwnd;
683 tc->snd_rxt_ts = tcp_tstamp (tc);
684 tcp_cc_congestion (tc);
686 /* Post retransmit update cwnd to ssthresh and account for the
687 * three segments that have left the network and should've been
688 * buffered at the receiver XXX */
689 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
690 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
692 tc->fr_occurences += 1;
693 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
697 tcp_cc_congestion_undo (tcp_connection_t * tc)
699 tc->cwnd = tc->prev_cwnd;
700 tc->ssthresh = tc->prev_ssthresh;
701 tcp_cc_undo_recovery (tc);
702 ASSERT (tc->rto_boff == 0);
703 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
707 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
709 return (tcp_in_recovery (tc) && tc->rto_boff == 1
711 && tcp_opts_tstamp (&tc->rcv_opts)
712 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
716 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
718 return (tcp_cc_is_spurious_timeout_rxt (tc));
722 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
726 /* If of of the two conditions lower hold, reset dupacks because
727 * we're probably after timeout (RFC6582 heuristics).
728 * If Cumulative ack does not cover more than congestion threshold,
730 * 1) The following doesn't hold: The congestion window is greater
731 * than SMSS bytes and the difference between highest_ack
732 * and prev_highest_ack is at most 4*SMSS bytes
733 * 2) Echoed timestamp in the last non-dup ack does not equal the
736 if (seq_leq (tc->snd_una, tc->snd_congestion)
737 && ((!(tc->cwnd > tc->snd_mss
738 && tc->bytes_acked <= 4 * tc->snd_mss))
739 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
745 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
749 tcp_cc_try_recover (tcp_connection_t *tc)
751 sack_scoreboard_hole_t *hole;
754 ASSERT (tcp_in_cong_recovery (tc));
756 if (tcp_cc_is_spurious_retransmit (tc))
758 tcp_cc_congestion_undo (tc);
762 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
764 tcp_recovery_off (tc);
766 /* Previous recovery left us congested. Continue sending as part
767 * of the current recovery event with an updated snd_congestion */
768 if (tc->sack_sb.sacked_bytes && tcp_in_fastrecovery (tc))
770 tc->snd_congestion = tc->snd_nxt;
774 tc->rxt_delivered = 0;
775 tc->snd_rxt_bytes = 0;
777 tc->prr_delivered = 0;
779 tc->flags &= ~TCP_CONN_RXT_PENDING;
781 hole = scoreboard_first_hole (&tc->sack_sb);
782 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
783 scoreboard_clear (&tc->sack_sb);
785 if (tcp_in_fastrecovery (tc) && !is_spurious)
786 tcp_cc_recovered (tc);
788 tcp_fastrecovery_off (tc);
789 tcp_fastrecovery_first_off (tc);
790 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
792 ASSERT (tc->rto_boff == 0);
793 ASSERT (!tcp_in_cong_recovery (tc));
794 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
800 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
802 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
804 /* Congestion avoidance */
805 tcp_cc_rcv_ack (tc, rs);
807 /* If a cumulative ack, make sure dupacks is 0 */
812 * One function to rule them all ... and in the darkness bind them
815 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
818 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
820 /* If reneging, wait for timer based retransmits */
821 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
825 * If not in recovery, figure out if we should enter
827 if (!tcp_in_cong_recovery (tc))
832 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
833 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
835 if (tcp_should_fastrecover (tc, has_sack))
837 tcp_cc_init_congestion (tc);
840 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
842 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
843 tcp_program_retransmit (tc);
850 * Already in recovery
854 * See if we can exit and stop retransmitting
856 if (seq_geq (tc->snd_una, tc->snd_congestion))
858 /* If successfully recovered, treat ack as congestion avoidance ack
859 * and return. Otherwise, we're still congested so process feedback */
860 if (!tcp_cc_try_recover (tc))
862 tcp_cc_rcv_ack (tc, rs);
868 * Process (re)transmit feedback. Output path uses this to decide how much
869 * more data to release into the network
873 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
874 tcp_fastrecovery_first_on (tc);
876 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
877 tc->prr_delivered += rs->delivered;
883 tc->rcv_dupacks += 1;
884 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
886 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
889 tc->prr_delivered += clib_min (tc->snd_mss,
890 tc->snd_nxt - tc->snd_una);
892 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
896 /* If partial ack, assume that the first un-acked segment was lost */
897 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
898 tcp_fastrecovery_first_on (tc);
901 tcp_program_retransmit (tc);
904 * Notify cc of the event
907 if (!tc->bytes_acked)
909 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
913 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
914 * reset dupacks to 0. Also needed if in congestion recovery */
917 if (tcp_in_recovery (tc))
918 tcp_cc_rcv_ack (tc, rs);
920 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
924 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
926 if (!tcp_in_cong_recovery (tc))
929 if (tcp_opts_sack_permitted (&tc->rcv_opts))
930 tcp_rcv_sacks (tc, tc->snd_una);
934 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
935 tcp_bt_sample_delivery_rate (tc, rs);
937 tcp_cc_handle_event (tc, rs, 1);
941 * Check if duplicate ack as per RFC5681 Sec. 2
944 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
947 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
948 && seq_gt (tc->snd_nxt, tc->snd_una)
949 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
950 && (prev_snd_wnd == tc->snd_wnd));
954 * Checks if ack is a congestion control event.
957 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
958 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
960 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
961 * defined to be 'duplicate' as well */
962 *is_dack = tc->sack_sb.last_sacked_bytes
963 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
965 return (*is_dack || tcp_in_cong_recovery (tc));
969 * Process incoming ACK
972 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
973 tcp_header_t * th, u32 * error)
975 u32 prev_snd_wnd, prev_snd_una;
976 tcp_rate_sample_t rs = { 0 };
979 TCP_EVT (TCP_EVT_CC_STAT, tc);
981 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
982 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
984 /* We've probably entered recovery and the peer still has some
985 * of the data we've sent. Update snd_nxt and accept the ack */
986 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
987 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
989 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
993 tc->errors.above_ack_wnd += 1;
994 *error = TCP_ERROR_ACK_FUTURE;
995 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
999 /* If old ACK, probably it's an old dupack */
1000 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1002 tc->errors.below_ack_wnd += 1;
1003 *error = TCP_ERROR_ACK_OLD;
1004 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1006 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1009 tcp_handle_old_ack (tc, &rs);
1011 /* Don't drop yet */
1018 * Looks okay, process feedback
1021 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1022 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1024 prev_snd_wnd = tc->snd_wnd;
1025 prev_snd_una = tc->snd_una;
1026 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1027 vnet_buffer (b)->tcp.ack_number,
1028 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1029 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1030 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1031 tcp_validate_txf_size (tc, tc->bytes_acked);
1033 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1034 tcp_bt_sample_delivery_rate (tc, &rs);
1036 rs.delivered = tc->bytes_acked + tc->sack_sb.last_sacked_bytes -
1037 tc->sack_sb.last_bytes_delivered;
1039 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1041 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1042 if (tc->bytes_acked)
1043 tcp_program_dequeue (wrk, tc);
1046 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1049 * Check if we have congestion event
1052 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1054 tcp_cc_handle_event (tc, &rs, is_dack);
1055 tc->dupacks_in += is_dack;
1056 if (!tcp_in_cong_recovery (tc))
1058 *error = TCP_ERROR_ACK_OK;
1061 *error = TCP_ERROR_ACK_DUP;
1062 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1068 * Update congestion control (slow start/congestion avoidance)
1070 tcp_cc_update (tc, &rs);
1071 *error = TCP_ERROR_ACK_OK;
1076 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1078 if (!tcp_disconnect_pending (tc))
1080 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1081 tcp_disconnect_pending_on (tc);
1086 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1088 u32 thread_index, *pending_disconnects, *pending_resets;
1089 tcp_connection_t *tc;
1092 if (vec_len (wrk->pending_disconnects))
1094 thread_index = wrk->vm->thread_index;
1095 pending_disconnects = wrk->pending_disconnects;
1096 for (i = 0; i < vec_len (pending_disconnects); i++)
1098 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1099 tcp_disconnect_pending_off (tc);
1100 session_transport_closing_notify (&tc->connection);
1102 vec_set_len (wrk->pending_disconnects, 0);
1105 if (vec_len (wrk->pending_resets))
1107 thread_index = wrk->vm->thread_index;
1108 pending_resets = wrk->pending_resets;
1109 for (i = 0; i < vec_len (pending_resets); i++)
1111 tc = tcp_connection_get (pending_resets[i], thread_index);
1112 tcp_disconnect_pending_off (tc);
1113 tcp_handle_rst (tc);
1115 vec_set_len (wrk->pending_resets, 0);
1120 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1123 /* Reject out-of-order fins */
1124 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1127 /* Account for the FIN and send ack */
1129 tc->flags |= TCP_CONN_FINRCVD;
1130 tcp_program_ack (tc);
1131 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1132 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1133 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1134 tcp_program_disconnect (wrk, tc);
1135 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1136 tcp_cfg.closewait_time);
1137 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1138 *error = TCP_ERROR_FIN_RCVD;
1141 /** Enqueue data for delivery to application */
1143 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1146 int written, error = TCP_ERROR_ENQUEUED;
1148 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1150 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1151 1 /* queue event */ , 1);
1153 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1155 /* Update rcv_nxt */
1156 if (PREDICT_TRUE (written == data_len))
1158 tc->rcv_nxt += written;
1159 tc->bytes_in += written;
1161 /* If more data written than expected, account for out-of-order bytes. */
1162 else if (written > data_len)
1164 tc->rcv_nxt += written;
1165 tc->bytes_in += data_len;
1166 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1168 else if (written > 0)
1170 /* We've written something but FIFO is probably full now */
1171 tc->rcv_nxt += written;
1172 tc->bytes_in += written;
1173 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1177 /* Packet made it through for ack processing */
1178 if (tc->rcv_wnd < tc->snd_mss)
1179 return TCP_ERROR_ZERO_RWND;
1181 return TCP_ERROR_FIFO_FULL;
1184 /* Update SACK list if need be */
1185 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
1187 /* Remove SACK blocks that have been delivered */
1188 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1194 /** Enqueue out-of-order data */
1196 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1202 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1205 /* Enqueue out-of-order data with relative offset */
1206 rv = session_enqueue_stream_connection (&tc->connection, b,
1207 vnet_buffer (b)->tcp.seq_number -
1208 tc->rcv_nxt, 0 /* queue event */ ,
1211 /* Nothing written */
1214 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1215 return TCP_ERROR_FIFO_FULL;
1218 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1219 tc->bytes_in += data_len;
1221 /* Update SACK list if in use */
1222 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1224 ooo_segment_t *newest;
1227 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1229 /* Get the newest segment from the fifo */
1230 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1233 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1234 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1235 start = tc->rcv_nxt + offset;
1236 end = start + ooo_segment_length (s0->rx_fifo, newest);
1237 tcp_update_sack_list (tc, start, end);
1238 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1239 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1243 return TCP_ERROR_ENQUEUED_OOO;
1247 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1249 u32 discard, first = b->current_length;
1250 vlib_main_t *vm = vlib_get_main ();
1252 /* Handle multi-buffer segments */
1253 if (n_bytes_to_drop > b->current_length)
1255 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1259 discard = clib_min (n_bytes_to_drop, b->current_length);
1260 vlib_buffer_advance (b, discard);
1261 b = vlib_get_buffer (vm, b->next_buffer);
1262 n_bytes_to_drop -= discard;
1264 while (n_bytes_to_drop);
1265 if (n_bytes_to_drop > first)
1266 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1269 vlib_buffer_advance (b, n_bytes_to_drop);
1270 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1275 * Receive buffer for connection and handle acks
1277 * It handles both in order or out-of-order data.
1280 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1283 u32 error, n_bytes_to_drop, n_data_bytes;
1285 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1286 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1287 ASSERT (n_data_bytes);
1288 tc->data_segs_in += 1;
1290 /* Make sure we don't consume trailing bytes */
1291 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1292 b->current_length = n_data_bytes;
1294 /* Handle out-of-order data */
1295 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1297 /* Old sequence numbers allowed through because they overlapped
1299 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1301 /* Completely in the past (possible retransmit). Ack
1302 * retransmissions since we may not have any data to send */
1303 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1305 tcp_program_dupack (tc);
1306 tc->errors.below_data_wnd++;
1307 error = TCP_ERROR_SEGMENT_OLD;
1311 /* Chop off the bytes in the past and see if what is left
1312 * can be enqueued in order */
1313 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1314 n_data_bytes -= n_bytes_to_drop;
1315 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1316 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1318 error = TCP_ERROR_SEGMENT_OLD;
1324 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1325 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1326 tcp_program_dupack (tc);
1327 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1328 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1329 tc->rcv_las + tc->rcv_wnd);
1335 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1336 * segments can be enqueued after fifo tail offset changes. */
1337 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1338 tcp_program_ack (tc);
1346 tcp_header_t tcp_header;
1347 tcp_connection_t tcp_connection;
1351 format_tcp_rx_trace (u8 * s, va_list * args)
1353 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1354 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1355 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1356 tcp_connection_t *tc = &t->tcp_connection;
1357 u32 indent = format_get_indent (s);
1359 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1360 format_tcp_state, tc->state, format_white_space, indent,
1361 format_tcp_header, &t->tcp_header, 128);
1367 format_tcp_rx_trace_short (u8 * s, va_list * args)
1369 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1370 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1371 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1373 s = format (s, "%d -> %d (%U)",
1374 clib_net_to_host_u16 (t->tcp_header.dst_port),
1375 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1376 t->tcp_connection.state);
1382 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1383 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1387 clib_memcpy_fast (&t0->tcp_connection, tc0,
1388 sizeof (t0->tcp_connection));
1392 th0 = tcp_buffer_hdr (b0);
1394 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1398 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1399 vlib_frame_t * frame, u8 is_ip4)
1403 n_left = frame->n_vectors;
1404 from = vlib_frame_vector_args (frame);
1408 tcp_connection_t *tc0;
1415 b0 = vlib_get_buffer (vm, bi0);
1417 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1419 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1420 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1422 th0 = tcp_buffer_hdr (b0);
1423 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1432 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
1433 u8 is_ip4, u32 evt, u32 val)
1436 vlib_node_increment_counter (vm, tcp4_node, evt, val);
1438 vlib_node_increment_counter (vm, tcp6_node, evt, val);
1441 #define tcp_maybe_inc_counter(node_id, err, count) \
1443 if (next0 != tcp_next_drop (is_ip4)) \
1444 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1445 tcp6_##node_id##_node.index, is_ip4, err, \
1448 #define tcp_inc_counter(node_id, err, count) \
1449 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
1450 tcp6_##node_id##_node.index, is_ip4, \
1452 #define tcp_maybe_inc_err_counter(cnts, err) \
1454 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
1456 #define tcp_inc_err_counter(cnts, err, val) \
1460 #define tcp_store_err_counters(node_id, cnts) \
1463 for (i = 0; i < TCP_N_ERROR; i++) \
1465 tcp_inc_counter(node_id, i, cnts[i]); \
1470 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1471 vlib_frame_t * frame, int is_ip4)
1473 u32 thread_index = vm->thread_index, errors = 0;
1474 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1475 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1476 u16 err_counters[TCP_N_ERROR] = { 0 };
1477 u32 n_left_from, *from;
1479 if (node->flags & VLIB_NODE_FLAG_TRACE)
1480 tcp_established_trace_frame (vm, node, frame, is_ip4);
1482 from = vlib_frame_vector_args (frame);
1483 n_left_from = frame->n_vectors;
1485 vlib_get_buffers (vm, from, bufs, n_left_from);
1488 while (n_left_from > 0)
1490 u32 error = TCP_ERROR_ACK_OK;
1491 tcp_connection_t *tc;
1494 if (n_left_from > 1)
1496 vlib_prefetch_buffer_header (b[1], LOAD);
1497 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1500 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1503 if (PREDICT_FALSE (tc == 0))
1505 error = TCP_ERROR_INVALID_CONNECTION;
1509 th = tcp_buffer_hdr (b[0]);
1511 /* TODO header prediction fast path */
1513 /* 1-4: check SEQ, RST, SYN */
1514 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1516 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1520 /* 5: check the ACK field */
1521 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1524 /* 6: check the URG bit TODO */
1526 /* 7: process the segment text */
1527 if (vnet_buffer (b[0])->tcp.data_len)
1528 error = tcp_segment_rcv (wrk, tc, b[0]);
1530 /* 8: check the FIN bit */
1531 if (PREDICT_FALSE (tcp_is_fin (th)))
1532 tcp_rcv_fin (wrk, tc, b[0], &error);
1535 tcp_inc_err_counter (err_counters, error, 1);
1541 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1543 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1544 tcp_store_err_counters (established, err_counters);
1545 tcp_handle_postponed_dequeues (wrk);
1546 tcp_handle_disconnects (wrk);
1547 vlib_buffer_free (vm, from, frame->n_vectors);
1549 return frame->n_vectors;
1552 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1553 vlib_node_runtime_t * node,
1554 vlib_frame_t * from_frame)
1556 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1559 VLIB_NODE_FN (tcp6_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, 0 /* is_ip4 */ );
1567 VLIB_REGISTER_NODE (tcp4_established_node) =
1569 .name = "tcp4-established",
1570 /* Takes a vector of packets. */
1571 .vector_size = sizeof (u32),
1572 .n_errors = TCP_N_ERROR,
1573 .error_counters = tcp_input_error_counters,
1574 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1577 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1578 foreach_tcp_state_next
1581 .format_trace = format_tcp_rx_trace_short,
1586 VLIB_REGISTER_NODE (tcp6_established_node) =
1588 .name = "tcp6-established",
1589 /* Takes a vector of packets. */
1590 .vector_size = sizeof (u32),
1591 .n_errors = TCP_N_ERROR,
1592 .error_counters = tcp_input_error_counters,
1593 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1596 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1597 foreach_tcp_state_next
1600 .format_trace = format_tcp_rx_trace_short,
1606 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1609 transport_connection_t *tmp = 0;
1616 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1619 u8 is_ip_valid = 0, val_l, val_r;
1621 if (tc->connection.is_ip4)
1623 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1625 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1626 &tc->connection.lcl_ip.ip4);
1627 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1628 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1629 &tc->connection.rmt_ip.ip4);
1630 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1631 is_ip_valid = val_l && val_r;
1635 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1637 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1638 &tc->connection.lcl_ip.ip6);
1639 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1640 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1641 &tc->connection.rmt_ip.ip6);
1642 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1643 is_ip_valid = val_l && val_r;
1646 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1647 && (tc->state == TCP_STATE_LISTEN
1648 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1652 handle = session_lookup_half_open_handle (&tc->connection);
1653 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1654 tc->c_proto, tc->c_is_ip4);
1658 if (tmp->lcl_port == hdr->dst_port
1659 && tmp->rmt_port == hdr->src_port)
1661 TCP_DBG ("half-open is valid!");
1670 * Lookup transport connection
1672 static tcp_connection_t *
1673 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1677 transport_connection_t *tconn;
1678 tcp_connection_t *tc;
1683 ip4 = vlib_buffer_get_current (b);
1684 tcp = ip4_next_header (ip4);
1685 tconn = session_lookup_connection_wt4 (fib_index,
1690 TRANSPORT_PROTO_TCP,
1691 thread_index, &is_filtered);
1692 tc = tcp_get_connection_from_transport (tconn);
1693 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1698 ip6 = vlib_buffer_get_current (b);
1699 tcp = ip6_next_header (ip6);
1700 tconn = session_lookup_connection_wt6 (fib_index,
1705 TRANSPORT_PROTO_TCP,
1706 thread_index, &is_filtered);
1707 tc = tcp_get_connection_from_transport (tconn);
1708 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1713 static tcp_connection_t *
1714 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1720 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1721 tcp_header_t *tcp = tcp_buffer_hdr (b);
1722 s = session_lookup_listener4 (fib_index,
1724 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1728 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1729 tcp_header_t *tcp = tcp_buffer_hdr (b);
1730 s = session_lookup_listener6 (fib_index,
1732 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1735 if (PREDICT_TRUE (s != 0))
1736 return tcp_get_connection_from_transport (transport_get_listener
1737 (TRANSPORT_PROTO_TCP,
1738 s->connection_index));
1744 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1745 u32 *from, u32 n_bufs)
1747 tcp_connection_t *tc = 0;
1752 for (i = 0; i < n_bufs; i++)
1754 b = vlib_get_buffer (vm, from[i]);
1755 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1758 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1759 t = vlib_add_trace (vm, node, b, sizeof (*t));
1760 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1765 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1767 vnet_main_t *vnm = vnet_get_main ();
1768 const dpo_id_t *dpo;
1769 const load_balance_t *lb;
1770 vnet_hw_interface_t *hw_if;
1771 u32 sw_if_idx, lb_idx;
1775 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1776 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1780 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1781 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1784 lb = load_balance_get (lb_idx);
1785 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1787 dpo = load_balance_get_bucket_i (lb, 0);
1789 sw_if_idx = dpo_get_urpf (dpo);
1790 if (PREDICT_FALSE (sw_if_idx == ~0))
1793 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1794 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1795 tc->cfg_flags |= TCP_CFG_F_TSO;
1799 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1800 vlib_frame_t *frame, int is_ip4)
1802 u32 n_left_from, *from, thread_index = vm->thread_index, errors = 0;
1803 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1804 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1806 from = vlib_frame_vector_args (frame);
1807 n_left_from = frame->n_vectors;
1809 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1810 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1812 vlib_get_buffers (vm, from, bufs, n_left_from);
1815 while (n_left_from > 0)
1817 u32 ack, seq, error = TCP_ERROR_NONE;
1818 tcp_connection_t *tc, *new_tc;
1821 tc = tcp_half_open_connection_get (
1822 vnet_buffer (b[0])->tcp.connection_index);
1823 if (PREDICT_FALSE (tc == 0))
1825 error = TCP_ERROR_INVALID_CONNECTION;
1829 /* Half-open completed or cancelled recently but the connection
1830 * was't removed yet by the owning thread */
1831 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1833 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1837 ack = vnet_buffer (b[0])->tcp.ack_number;
1838 seq = vnet_buffer (b[0])->tcp.seq_number;
1839 tcp = tcp_buffer_hdr (b[0]);
1841 /* Crude check to see if the connection handle does not match
1842 * the packet. Probably connection just switched to established */
1843 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1844 tcp->src_port != tc->c_rmt_port))
1846 error = TCP_ERROR_INVALID_CONNECTION;
1850 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1852 error = TCP_ERROR_SEGMENT_INVALID;
1856 /* SYNs consume sequence numbers */
1857 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1860 * 1. check the ACK bit
1864 * If the ACK bit is set
1865 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1866 * the RST bit is set, if so drop the segment and return)
1867 * <SEQ=SEG.ACK><CTL=RST>
1868 * and discard the segment. Return.
1869 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1873 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1876 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1877 error = TCP_ERROR_RCV_WND;
1881 /* Make sure ACK is valid */
1882 if (seq_gt (tc->snd_una, ack))
1884 error = TCP_ERROR_ACK_INVALID;
1890 * 2. check the RST bit
1895 /* If ACK is acceptable, signal client that peer is not
1896 * willing to accept connection and drop connection*/
1898 tcp_rcv_rst (wrk, tc);
1899 error = TCP_ERROR_RST_RCVD;
1904 * 3. check the security and precedence (skipped)
1908 * 4. check the SYN bit
1911 /* No SYN flag. Drop. */
1914 error = TCP_ERROR_SEGMENT_INVALID;
1919 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1921 error = TCP_ERROR_OPTIONS;
1925 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1926 * current thread pool. */
1927 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1928 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1930 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1932 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1934 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1935 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1938 if (tcp_opts_wscale (&new_tc->rcv_opts))
1939 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1941 new_tc->rcv_wscale = 0;
1943 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1944 << new_tc->snd_wscale;
1945 new_tc->snd_wl1 = seq;
1946 new_tc->snd_wl2 = ack;
1948 tcp_connection_init_vars (new_tc);
1950 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1951 if (PREDICT_TRUE (tcp_ack (tcp)))
1953 /* Our SYN is ACKed: we have iss < ack = snd_una */
1955 /* TODO Dequeue acknowledged segments if we support Fast Open */
1956 new_tc->snd_una = ack;
1957 new_tc->state = TCP_STATE_ESTABLISHED;
1959 /* Make sure las is initialized for the wnd computation */
1960 new_tc->rcv_las = new_tc->rcv_nxt;
1962 /* Notify app that we have connection. If session layer can't
1963 * allocate session send reset */
1964 if (session_stream_connect_notify (&new_tc->connection,
1967 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1968 tcp_connection_cleanup (new_tc);
1969 error = TCP_ERROR_CREATE_SESSION_FAIL;
1973 transport_fifos_init_ooo (&new_tc->connection);
1974 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1975 /* Update rtt with the syn-ack sample */
1976 tcp_estimate_initial_rtt (new_tc);
1977 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1978 error = TCP_ERROR_SYN_ACKS_RCVD;
1980 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1983 new_tc->state = TCP_STATE_SYN_RCVD;
1985 /* Notify app that we have connection */
1986 if (session_stream_connect_notify (&new_tc->connection,
1989 tcp_connection_cleanup (new_tc);
1990 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1991 TCP_EVT (TCP_EVT_RST_SENT, tc);
1992 error = TCP_ERROR_CREATE_SESSION_FAIL;
1996 transport_fifos_init_ooo (&new_tc->connection);
1997 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1999 tcp_init_snd_vars (new_tc);
2000 tcp_send_synack (new_tc);
2001 error = TCP_ERROR_SYNS_RCVD;
2005 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
2006 tcp_check_tx_offload (new_tc, is_ip4);
2008 /* Read data, if any */
2009 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
2011 clib_warning ("rcvd data in syn-sent");
2012 error = tcp_segment_rcv (wrk, new_tc, b[0]);
2013 if (error == TCP_ERROR_ACK_OK)
2014 error = TCP_ERROR_SYN_ACKS_RCVD;
2018 /* Send ack now instead of programming it because connection was
2019 * just established and it's not optional. */
2020 tcp_send_ack (new_tc);
2025 /* If this is not the owning thread, wait for syn retransmit to
2026 * expire and cleanup then */
2027 if (tcp_half_open_connection_cleanup (tc))
2028 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
2034 tcp_inc_counter (syn_sent, error, 1);
2038 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2039 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2040 vlib_buffer_free (vm, from, frame->n_vectors);
2041 tcp_handle_disconnects (wrk);
2043 return frame->n_vectors;
2046 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2047 vlib_node_runtime_t * node,
2048 vlib_frame_t * from_frame)
2050 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2053 VLIB_NODE_FN (tcp6_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, 0 /* is_ip4 */ );
2061 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2063 .name = "tcp4-syn-sent",
2064 /* Takes a vector of packets. */
2065 .vector_size = sizeof (u32),
2066 .n_errors = TCP_N_ERROR,
2067 .error_counters = tcp_input_error_counters,
2068 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2071 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2072 foreach_tcp_state_next
2075 .format_trace = format_tcp_rx_trace_short,
2080 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2082 .name = "tcp6-syn-sent",
2083 /* Takes a vector of packets. */
2084 .vector_size = sizeof (u32),
2085 .n_errors = TCP_N_ERROR,
2086 .error_counters = tcp_input_error_counters,
2087 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2090 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2091 foreach_tcp_state_next
2094 .format_trace = format_tcp_rx_trace_short,
2099 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2100 u32 *from, u32 n_bufs)
2102 u32 thread_index = vm->thread_index;
2103 tcp_connection_t *tc = 0;
2108 for (i = 0; i < n_bufs; i++)
2110 b = vlib_get_buffer (vm, from[i]);
2111 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2113 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2115 t = vlib_add_trace (vm, node, b, sizeof (*t));
2116 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2121 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2122 * as per RFC793 p. 64
2125 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2126 vlib_frame_t *frame, int is_ip4)
2128 u32 thread_index = vm->thread_index, errors, n_left_from, *from, max_deq;
2129 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2130 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2132 from = vlib_frame_vector_args (frame);
2133 n_left_from = frame->n_vectors;
2135 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2136 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2138 vlib_get_buffers (vm, from, bufs, n_left_from);
2141 while (n_left_from > 0)
2143 u32 error = TCP_ERROR_NONE;
2144 tcp_header_t *tcp = 0;
2145 tcp_connection_t *tc;
2148 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2150 if (PREDICT_FALSE (tc == 0))
2152 error = TCP_ERROR_INVALID_CONNECTION;
2156 tcp = tcp_buffer_hdr (b[0]);
2157 is_fin = tcp_is_fin (tcp);
2161 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2163 tcp_connection_t *tmp;
2164 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2166 if (tmp->state != tc->state)
2168 if (tc->state != TCP_STATE_CLOSED)
2169 clib_warning ("state changed");
2176 * Special treatment for CLOSED
2178 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2180 error = TCP_ERROR_CONNECTION_CLOSED;
2185 * For all other states (except LISTEN)
2188 /* 1-4: check SEQ, RST, SYN */
2189 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2192 /* 5: check the ACK field */
2195 case TCP_STATE_SYN_RCVD:
2197 /* Make sure the segment is exactly right */
2198 if (tc->rcv_nxt != vnet_buffer (b[0])->tcp.seq_number || is_fin)
2200 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2201 error = TCP_ERROR_SEGMENT_INVALID;
2206 * If the segment acknowledgment is not acceptable, form a
2208 * <SEQ=SEG.ACK><CTL=RST>
2211 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2213 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2214 error = TCP_ERROR_SEGMENT_INVALID;
2218 /* Update rtt and rto */
2219 tcp_estimate_initial_rtt (tc);
2220 tcp_connection_tx_pacer_update (tc);
2222 /* Switch state to ESTABLISHED */
2223 tc->state = TCP_STATE_ESTABLISHED;
2224 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2226 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2227 tcp_check_tx_offload (tc, is_ip4);
2229 /* Initialize session variables */
2230 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2231 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2232 << tc->rcv_opts.wscale;
2233 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2234 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2236 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2237 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2238 if (session_stream_accept_notify (&tc->connection))
2240 error = TCP_ERROR_MSG_QUEUE_FULL;
2241 tcp_send_reset (tc);
2242 session_transport_delete_notify (&tc->connection);
2243 tcp_connection_cleanup (tc);
2246 error = TCP_ERROR_ACK_OK;
2248 case TCP_STATE_ESTABLISHED:
2249 /* We can get packets in established state here because they
2250 * were enqueued before state change */
2251 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2255 case TCP_STATE_FIN_WAIT_1:
2256 /* In addition to the processing for the ESTABLISHED state, if
2257 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2258 * continue processing in that state. */
2259 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2262 /* Still have to send the FIN */
2263 if (tc->flags & TCP_CONN_FINPNDG)
2265 /* TX fifo finally drained */
2266 max_deq = transport_max_tx_dequeue (&tc->connection);
2267 if (max_deq <= tc->burst_acked)
2269 /* If a fin was received and data was acked extend wait */
2270 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2271 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2272 tcp_cfg.closewait_time);
2274 /* If FIN is ACKed */
2275 else if (tc->snd_una == tc->snd_nxt)
2277 /* Stop all retransmit timers because we have nothing more
2279 tcp_connection_timers_reset (tc);
2281 /* We already have a FIN but didn't transition to CLOSING
2282 * because of outstanding tx data. Close the connection. */
2283 if (tc->flags & TCP_CONN_FINRCVD)
2285 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2286 session_transport_closed_notify (&tc->connection);
2287 tcp_program_cleanup (wrk, tc);
2291 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2292 /* Enable waitclose because we're willing to wait for peer's
2293 * FIN but not indefinitely. */
2294 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2295 tcp_cfg.finwait2_time);
2297 /* Don't try to deq the FIN acked */
2298 if (tc->burst_acked > 1)
2299 session_tx_fifo_dequeue_drop (&tc->connection,
2300 tc->burst_acked - 1);
2301 tc->burst_acked = 0;
2304 case TCP_STATE_FIN_WAIT_2:
2305 /* In addition to the processing for the ESTABLISHED state, if
2306 * the retransmission queue is empty, the user's CLOSE can be
2307 * acknowledged ("ok") but do not delete the TCB. */
2308 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2310 tc->burst_acked = 0;
2312 case TCP_STATE_CLOSE_WAIT:
2313 /* Do the same processing as for the ESTABLISHED state. */
2314 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2317 if (!(tc->flags & TCP_CONN_FINPNDG))
2320 /* Still have outstanding tx data */
2321 max_deq = transport_max_tx_dequeue (&tc->connection);
2322 if (max_deq > tc->burst_acked)
2326 tcp_connection_timers_reset (tc);
2327 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2328 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2329 tcp_cfg.lastack_time);
2331 case TCP_STATE_CLOSING:
2332 /* In addition to the processing for the ESTABLISHED state, if
2333 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2334 * otherwise ignore the segment. */
2335 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2338 if (tc->snd_una != tc->snd_nxt)
2341 tcp_connection_timers_reset (tc);
2342 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2343 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2344 tcp_cfg.timewait_time);
2345 session_transport_closed_notify (&tc->connection);
2349 case TCP_STATE_LAST_ACK:
2350 /* The only thing that [should] arrive in this state is an
2351 * acknowledgment of our FIN. If our FIN is now acknowledged,
2352 * delete the TCB, enter the CLOSED state, and return. */
2354 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2357 /* Apparently our ACK for the peer's FIN was lost */
2358 if (is_fin && tc->snd_una != tc->snd_nxt)
2364 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2365 session_transport_closed_notify (&tc->connection);
2367 /* Don't free the connection from the data path since
2368 * we can't ensure that we have no packets already enqueued
2369 * to output. Rely instead on the waitclose timer */
2370 tcp_connection_timers_reset (tc);
2371 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2376 case TCP_STATE_TIME_WAIT:
2377 /* The only thing that can arrive in this state is a
2378 * retransmission of the remote FIN. Acknowledge it, and restart
2379 * the 2 MSL timeout. */
2381 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2387 tcp_program_ack (tc);
2388 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2389 tcp_cfg.timewait_time);
2397 /* 6: check the URG bit TODO */
2399 /* 7: process the segment text */
2402 case TCP_STATE_ESTABLISHED:
2403 case TCP_STATE_FIN_WAIT_1:
2404 case TCP_STATE_FIN_WAIT_2:
2405 if (vnet_buffer (b[0])->tcp.data_len)
2406 error = tcp_segment_rcv (wrk, tc, b[0]);
2407 /* Don't accept out of order fins lower */
2408 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2411 case TCP_STATE_CLOSE_WAIT:
2412 case TCP_STATE_CLOSING:
2413 case TCP_STATE_LAST_ACK:
2414 case TCP_STATE_TIME_WAIT:
2415 /* This should not occur, since a FIN has been received from the
2416 * remote side. Ignore the segment text. */
2420 /* 8: check the FIN bit */
2424 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2428 case TCP_STATE_ESTABLISHED:
2429 /* Account for the FIN and send ack */
2431 tcp_program_ack (tc);
2432 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2433 tcp_program_disconnect (wrk, tc);
2434 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2435 tcp_cfg.closewait_time);
2437 case TCP_STATE_SYN_RCVD:
2438 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2439 * notified yet, set a cleanup timer instead of relying on
2440 * disconnect notify and the implicit close call. */
2441 tcp_connection_timers_reset (tc);
2444 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2445 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2446 tcp_cfg.lastack_time);
2448 case TCP_STATE_CLOSE_WAIT:
2449 case TCP_STATE_CLOSING:
2450 case TCP_STATE_LAST_ACK:
2453 case TCP_STATE_FIN_WAIT_1:
2456 if (tc->flags & TCP_CONN_FINPNDG)
2458 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2459 * sending it. Since we already received a fin, do not wait
2461 tc->flags |= TCP_CONN_FINRCVD;
2462 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2463 tcp_cfg.closewait_time);
2467 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2468 tcp_program_ack (tc);
2469 /* Wait for ACK for our FIN but not forever */
2470 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2471 tcp_cfg.closing_time);
2474 case TCP_STATE_FIN_WAIT_2:
2475 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2477 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2478 tcp_connection_timers_reset (tc);
2479 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2480 tcp_cfg.timewait_time);
2481 tcp_program_ack (tc);
2482 session_transport_closed_notify (&tc->connection);
2484 case TCP_STATE_TIME_WAIT:
2485 /* Remain in the TIME-WAIT state. Restart the time-wait
2488 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2489 tcp_cfg.timewait_time);
2492 error = TCP_ERROR_FIN_RCVD;
2498 tcp_inc_counter (rcv_process, error, 1);
2501 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2503 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2504 tcp_handle_postponed_dequeues (wrk);
2505 tcp_handle_disconnects (wrk);
2506 vlib_buffer_free (vm, from, frame->n_vectors);
2508 return frame->n_vectors;
2511 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2512 vlib_node_runtime_t * node,
2513 vlib_frame_t * from_frame)
2515 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2518 VLIB_NODE_FN (tcp6_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, 0 /* is_ip4 */ );
2526 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2528 .name = "tcp4-rcv-process",
2529 /* Takes a vector of packets. */
2530 .vector_size = sizeof (u32),
2531 .n_errors = TCP_N_ERROR,
2532 .error_counters = tcp_input_error_counters,
2533 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2536 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2537 foreach_tcp_state_next
2540 .format_trace = format_tcp_rx_trace_short,
2545 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2547 .name = "tcp6-rcv-process",
2548 /* Takes a vector of packets. */
2549 .vector_size = sizeof (u32),
2550 .n_errors = TCP_N_ERROR,
2551 .error_counters = tcp_input_error_counters,
2552 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2555 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2556 foreach_tcp_state_next
2559 .format_trace = format_tcp_rx_trace_short,
2564 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2565 u32 *to_next, u32 n_bufs)
2567 tcp_connection_t *tc = 0;
2572 for (i = 0; i < n_bufs; i++)
2574 b = vlib_get_buffer (vm, to_next[i]);
2575 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2577 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2578 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2579 t = vlib_add_trace (vm, node, b, sizeof (*t));
2580 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2585 * SYN received in TIME-WAIT state.
2588 * "When a connection is [...] on TIME-WAIT state [...]
2589 * [a TCP] MAY accept a new SYN from the remote TCP to
2590 * reopen the connection directly, if it:
2592 * (1) assigns its initial sequence number for the new
2593 * connection to be larger than the largest sequence
2594 * number it used on the previous connection incarnation,
2597 * (2) returns to TIME-WAIT state if the SYN turns out
2598 * to be an old duplicate".
2600 * The function returns true if the syn can be accepted during
2601 * connection time-wait (port reuse). In this case the function
2602 * also calculates what the iss should be for the new connection.
2605 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2607 int paws_reject = tcp_segment_check_paws (tc);
2611 /* Check that the SYN arrived out of window. We accept it */
2613 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2614 (tcp_opts_tstamp (&tc->rcv_opts) &&
2615 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2617 /* Set the iss of the new connection to be the largest sequence number
2618 * the old peer would have accepted and add some random number
2620 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2621 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2631 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2632 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2633 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2634 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2640 * LISTEN state processing as per RFC 793 p. 65
2643 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2644 vlib_frame_t *frame, int is_ip4)
2646 u32 n_left_from, *from, n_syns = 0;
2647 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2648 u32 thread_index = vm->thread_index;
2651 from = vlib_frame_vector_args (frame);
2652 n_left_from = frame->n_vectors;
2654 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2655 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2657 vlib_get_buffers (vm, from, bufs, n_left_from);
2660 while (n_left_from > 0)
2662 tcp_connection_t *lc, *child;
2664 /* Flags initialized with connection state after lookup */
2665 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2667 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2669 else /* We are in TimeWait state*/
2671 tcp_connection_t *tc;
2672 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2674 if (tc->state != TCP_STATE_TIME_WAIT)
2676 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2680 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2682 /* This SYN can't be accepted */
2683 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2687 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2688 /* clean up the old session */
2689 tcp_connection_del (tc);
2690 /* listener was cleaned up */
2693 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
2698 /* Make sure connection wasn't just created */
2700 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2701 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2703 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2707 /* Create child session. For syn-flood protection use filter */
2709 /* 1. first check for an RST: handled by input dispatch */
2711 /* 2. second check for an ACK: handled by input dispatch */
2713 /* 3. check for a SYN (did that already) */
2715 /* Create child session and send SYN-ACK */
2716 child = tcp_connection_alloc (thread_index);
2718 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2720 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
2721 tcp_connection_free (child);
2725 tcp_init_w_buffer (child, b[0], is_ip4);
2727 child->state = TCP_STATE_SYN_RCVD;
2728 child->c_fib_index = lc->c_fib_index;
2729 child->cc_algo = lc->cc_algo;
2731 /* In the regular case, the tw_iss will be zero, but
2732 * in the special case of syn arriving in time_wait state, the value
2733 * will be set according to rfc 1122
2735 child->iss = tw_iss;
2736 tcp_connection_init_vars (child);
2737 child->rto = TCP_RTO_MIN;
2740 * This initializes elog track, must be done before synack.
2741 * We also do it before possible tcp_connection_cleanup() as it
2742 * generates TCP_EVT_DELETE event.
2744 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2746 if (session_stream_accept (&child->connection, lc->c_s_index,
2747 lc->c_thread_index, 0 /* notify */ ))
2749 tcp_connection_cleanup (child);
2750 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
2754 transport_fifos_init_ooo (&child->connection);
2755 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2757 tcp_send_synack (child);
2765 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2766 vlib_buffer_free (vm, from, frame->n_vectors);
2768 return frame->n_vectors;
2771 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2772 vlib_frame_t * from_frame)
2774 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2777 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2778 vlib_frame_t * from_frame)
2780 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2784 VLIB_REGISTER_NODE (tcp4_listen_node) =
2786 .name = "tcp4-listen",
2787 /* Takes a vector of packets. */
2788 .vector_size = sizeof (u32),
2789 .n_errors = TCP_N_ERROR,
2790 .error_counters = tcp_input_error_counters,
2791 .n_next_nodes = TCP_LISTEN_N_NEXT,
2794 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2795 foreach_tcp_state_next
2798 .format_trace = format_tcp_rx_trace_short,
2803 VLIB_REGISTER_NODE (tcp6_listen_node) =
2805 .name = "tcp6-listen",
2806 /* Takes a vector of packets. */
2807 .vector_size = sizeof (u32),
2808 .n_errors = TCP_N_ERROR,
2809 .error_counters = tcp_input_error_counters,
2810 .n_next_nodes = TCP_LISTEN_N_NEXT,
2813 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2814 foreach_tcp_state_next
2817 .format_trace = format_tcp_rx_trace_short,
2821 typedef enum _tcp_input_next
2823 TCP_INPUT_NEXT_DROP,
2824 TCP_INPUT_NEXT_LISTEN,
2825 TCP_INPUT_NEXT_RCV_PROCESS,
2826 TCP_INPUT_NEXT_SYN_SENT,
2827 TCP_INPUT_NEXT_ESTABLISHED,
2828 TCP_INPUT_NEXT_RESET,
2829 TCP_INPUT_NEXT_PUNT,
2833 #define foreach_tcp4_input_next \
2834 _ (DROP, "ip4-drop") \
2835 _ (LISTEN, "tcp4-listen") \
2836 _ (RCV_PROCESS, "tcp4-rcv-process") \
2837 _ (SYN_SENT, "tcp4-syn-sent") \
2838 _ (ESTABLISHED, "tcp4-established") \
2839 _ (RESET, "tcp4-reset") \
2840 _ (PUNT, "ip4-punt")
2842 #define foreach_tcp6_input_next \
2843 _ (DROP, "ip6-drop") \
2844 _ (LISTEN, "tcp6-listen") \
2845 _ (RCV_PROCESS, "tcp6-rcv-process") \
2846 _ (SYN_SENT, "tcp6-syn-sent") \
2847 _ (ESTABLISHED, "tcp6-established") \
2848 _ (RESET, "tcp6-reset") \
2849 _ (PUNT, "ip6-punt")
2851 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2854 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2855 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
2857 tcp_connection_t *tc;
2862 for (i = 0; i < n_bufs; i++)
2864 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2866 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2867 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
2869 tcp = vlib_buffer_get_current (bs[i]);
2870 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
2876 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2878 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2880 *next = TCP_INPUT_NEXT_DROP;
2882 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2884 *next = TCP_INPUT_NEXT_PUNT;
2885 *error = TCP_ERROR_PUNT;
2889 *next = TCP_INPUT_NEXT_RESET;
2890 *error = TCP_ERROR_NO_LISTENER;
2895 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
2896 vlib_buffer_t * b, u16 * next,
2897 vlib_node_runtime_t * error_node)
2903 tcp = tcp_buffer_hdr (b);
2904 flags = tcp->flags & filter_flags;
2905 *next = tm->dispatch_table[tc->state][flags].next;
2906 error = tm->dispatch_table[tc->state][flags].error;
2909 /* Track connection state when packet was received. It is required
2910 * for @ref tcp46_listen_inline to detect whether we reached
2911 * the node as a result of a SYN packet received while in time-wait
2912 * state. In this case the connection_index in vnet buffer will point
2913 * to the existing tcp connection and not the listener
2915 vnet_buffer (b)->tcp.flags = tc->state;
2917 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2919 b->error = error_node->errors[error];
2920 if (error == TCP_ERROR_DISPATCH)
2921 clib_warning ("tcp conn %u disp error state %U flags %U",
2922 tc->c_c_index, format_tcp_state, tc->state,
2923 format_tcp_flags, (int) flags);
2928 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2929 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2931 u32 n_left_from, *from, thread_index = vm->thread_index;
2932 tcp_main_t *tm = vnet_get_tcp_main ();
2933 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2934 u16 nexts[VLIB_FRAME_SIZE], *next;
2936 tcp_update_time_now (tcp_get_worker (thread_index));
2938 from = vlib_frame_vector_args (frame);
2939 n_left_from = frame->n_vectors;
2940 vlib_get_buffers (vm, from, bufs, n_left_from);
2945 while (n_left_from >= 4)
2947 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2948 tcp_connection_t *tc0, *tc1;
2951 vlib_prefetch_buffer_header (b[2], STORE);
2952 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2954 vlib_prefetch_buffer_header (b[3], STORE);
2955 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2958 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2960 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2962 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2965 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2967 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2968 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2970 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2971 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2973 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2974 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2978 if (PREDICT_TRUE (tc0 != 0))
2980 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2981 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2982 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
2986 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2987 b[0]->error = node->errors[error0];
2990 if (PREDICT_TRUE (tc1 != 0))
2992 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2993 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2994 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], node);
2998 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2999 b[1]->error = node->errors[error1];
3007 while (n_left_from > 0)
3009 tcp_connection_t *tc0;
3010 u32 error0 = TCP_ERROR_NO_LISTENER;
3012 if (n_left_from > 1)
3014 vlib_prefetch_buffer_header (b[1], STORE);
3015 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3018 next[0] = TCP_INPUT_NEXT_DROP;
3019 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3021 if (PREDICT_TRUE (tc0 != 0))
3023 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3024 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3025 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], node);
3029 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3030 b[0]->error = node->errors[error0];
3038 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3039 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3041 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3042 return frame->n_vectors;
3045 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3046 vlib_node_runtime_t * node,
3047 vlib_frame_t * from_frame)
3049 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3050 1 /* is_nolookup */ );
3053 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3054 vlib_node_runtime_t * node,
3055 vlib_frame_t * from_frame)
3057 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3058 1 /* is_nolookup */ );
3062 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3064 .name = "tcp4-input-nolookup",
3065 /* Takes a vector of packets. */
3066 .vector_size = sizeof (u32),
3067 .n_errors = TCP_N_ERROR,
3068 .error_counters = tcp_input_error_counters,
3069 .n_next_nodes = TCP_INPUT_N_NEXT,
3072 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3073 foreach_tcp4_input_next
3076 .format_buffer = format_tcp_header,
3077 .format_trace = format_tcp_rx_trace,
3082 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3084 .name = "tcp6-input-nolookup",
3085 /* Takes a vector of packets. */
3086 .vector_size = sizeof (u32),
3087 .n_errors = TCP_N_ERROR,
3088 .error_counters = tcp_input_error_counters,
3089 .n_next_nodes = TCP_INPUT_N_NEXT,
3092 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3093 foreach_tcp6_input_next
3096 .format_buffer = format_tcp_header,
3097 .format_trace = format_tcp_rx_trace,
3101 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3102 vlib_frame_t * from_frame)
3104 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3105 0 /* is_nolookup */ );
3108 VLIB_NODE_FN (tcp6_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, 0 /* is_ip4 */ ,
3112 0 /* is_nolookup */ );
3116 VLIB_REGISTER_NODE (tcp4_input_node) =
3118 .name = "tcp4-input",
3119 /* Takes a vector of packets. */
3120 .vector_size = sizeof (u32),
3121 .n_errors = TCP_N_ERROR,
3122 .error_counters = tcp_input_error_counters,
3123 .n_next_nodes = TCP_INPUT_N_NEXT,
3126 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3127 foreach_tcp4_input_next
3130 .format_buffer = format_tcp_header,
3131 .format_trace = format_tcp_rx_trace,
3136 VLIB_REGISTER_NODE (tcp6_input_node) =
3138 .name = "tcp6-input",
3139 /* Takes a vector of packets. */
3140 .vector_size = sizeof (u32),
3141 .n_errors = TCP_N_ERROR,
3142 .error_counters = tcp_input_error_counters,
3143 .n_next_nodes = TCP_INPUT_N_NEXT,
3146 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3147 foreach_tcp6_input_next
3150 .format_buffer = format_tcp_header,
3151 .format_trace = format_tcp_rx_trace,
3155 #ifndef CLIB_MARCH_VARIANT
3157 tcp_check_gso (tcp_connection_t *tc)
3159 tcp_check_tx_offload (tc, tc->c_is_ip4);
3163 tcp_dispatch_table_init (tcp_main_t * tm)
3166 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3167 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3169 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3170 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3173 #define _(t,f,n,e) \
3175 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3176 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3179 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3180 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3181 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3182 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3183 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3184 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3185 TCP_ERROR_ACK_INVALID);
3186 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3187 TCP_ERROR_SEGMENT_INVALID);
3188 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3189 TCP_ERROR_SEGMENT_INVALID);
3190 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3191 TCP_ERROR_INVALID_CONNECTION);
3192 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3193 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3194 TCP_ERROR_SEGMENT_INVALID);
3195 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3196 TCP_ERROR_SEGMENT_INVALID);
3197 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3198 TCP_ERROR_SEGMENT_INVALID);
3199 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3200 TCP_ERROR_SEGMENT_INVALID);
3201 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3202 TCP_ERROR_SEGMENT_INVALID);
3203 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3204 TCP_ERROR_SEGMENT_INVALID);
3205 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3206 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3207 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3208 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3209 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3210 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3212 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3213 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3215 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3217 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3218 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3220 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3222 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3224 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3225 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3226 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3228 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3229 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3230 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3231 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3232 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3233 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3235 /* SYN-ACK for a SYN */
3236 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3238 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3239 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3240 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3242 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3243 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3245 /* ACK for for established connection -> tcp-established. */
3246 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3247 /* FIN for for established connection -> tcp-established. */
3248 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3249 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3251 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3253 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3254 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3255 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3257 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3258 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3259 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3260 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3261 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3262 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3263 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3264 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3266 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3267 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3269 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3271 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3272 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3273 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3274 /* ACK or FIN-ACK to our FIN */
3275 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3276 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3278 /* FIN in reply to our FIN from the other side */
3279 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3280 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3281 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3283 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3284 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3285 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3286 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3287 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3288 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3289 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3291 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3292 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3293 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3294 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3296 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3298 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3299 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3300 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3301 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3303 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3304 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3305 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3306 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3308 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3310 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3311 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3312 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3313 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3315 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3316 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3318 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3320 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3321 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3322 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3324 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3325 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3326 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3327 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3328 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3329 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3330 /* FIN confirming that the peer (app) has closed */
3331 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3332 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3333 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3335 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3336 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3338 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3339 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3340 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3342 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3343 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3345 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3346 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3347 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3348 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3349 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3351 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3353 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3354 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3355 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3357 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3358 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3359 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3360 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3361 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3362 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3363 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3364 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3366 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3367 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3369 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3371 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3372 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3373 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3374 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3375 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3377 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3378 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3380 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3381 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3382 * incoming segment not containing a RST causes a RST to be sent in
3384 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3385 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3386 TCP_ERROR_CONNECTION_CLOSED);
3387 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3388 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3389 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3390 TCP_ERROR_CONNECTION_CLOSED);
3394 static clib_error_t *
3395 tcp_input_init (vlib_main_t * vm)
3397 clib_error_t *error = 0;
3398 tcp_main_t *tm = vnet_get_tcp_main ();
3400 if ((error = vlib_call_init_function (vm, tcp_init)))
3403 /* Initialize dispatch table. */
3404 tcp_dispatch_table_init (tm);
3409 VLIB_INIT_FUNCTION (tcp_input_init);
3411 #endif /* CLIB_MARCH_VARIANT */
3414 * fd.io coding-style-patch-verification: ON
3417 * eval: (c-set-style "gnu")