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 typedef enum _tcp_input_next
81 TCP_INPUT_NEXT_LISTEN,
82 TCP_INPUT_NEXT_RCV_PROCESS,
83 TCP_INPUT_NEXT_SYN_SENT,
84 TCP_INPUT_NEXT_ESTABLISHED,
90 #define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
91 : TCP_NEXT_TCP6_OUTPUT)
93 #define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
97 * Validate segment sequence number. As per RFC793:
99 * Segment Receive Test
101 * ------- ------- -------------------------------------------
102 * 0 0 SEG.SEQ = RCV.NXT
103 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
104 * >0 0 not acceptable
105 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
106 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
108 * This ultimately consists in checking if segment falls within the window.
109 * The one important difference compared to RFC793 is that we use rcv_las,
110 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
111 * peer's reference when computing our receive window.
114 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
115 * however, is too strict when we have retransmits. Instead we just check that
116 * the seq is not beyond the right edge and that the end of the segment is not
117 * less than the left edge.
119 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
120 * use rcv_nxt in the right edge window test instead of rcv_las.
124 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
126 return (seq_geq (end_seq, tc->rcv_las)
127 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
131 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
132 * timestamp to echo and it's less than tsval_recent, drop segment
133 * but still send an ACK in order to retain TCP's mechanism for detecting
134 * and recovering from half-open connections
136 * Or at least that's what the theory says. It seems that this might not work
137 * very well with packet reordering and fast retransmit. XXX
140 tcp_segment_check_paws (tcp_connection_t * tc)
142 return tcp_opts_tstamp (&tc->rcv_opts)
143 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
147 * Update tsval recent
150 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
153 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
154 * of an incoming segment:
155 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
156 * then the TSval from the segment is copied to TS.Recent;
157 * otherwise, the TSval is ignored.
159 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
160 && seq_leq (tc->rcv_las, seq_end))
162 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
163 tc->tsval_recent = tc->rcv_opts.tsval;
164 tc->tsval_recent_age = tcp_time_tstamp (tc->c_thread_index);
169 tcp_handle_rst (tcp_connection_t * tc)
171 switch (tc->rst_state)
173 case TCP_STATE_SYN_RCVD:
174 /* Cleanup everything. App wasn't notified yet */
175 session_transport_delete_notify (&tc->connection);
176 tcp_connection_cleanup (tc);
178 case TCP_STATE_SYN_SENT:
179 session_stream_connect_notify (&tc->connection, SESSION_E_REFUSED);
180 tcp_connection_cleanup (tc);
182 case TCP_STATE_ESTABLISHED:
183 session_transport_reset_notify (&tc->connection);
184 session_transport_closed_notify (&tc->connection);
186 case TCP_STATE_CLOSE_WAIT:
187 case TCP_STATE_FIN_WAIT_1:
188 case TCP_STATE_FIN_WAIT_2:
189 case TCP_STATE_CLOSING:
190 case TCP_STATE_LAST_ACK:
191 session_transport_closed_notify (&tc->connection);
193 case TCP_STATE_CLOSED:
194 case TCP_STATE_TIME_WAIT:
197 TCP_DBG ("reset state: %u", tc->state);
202 tcp_program_reset_ntf (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
204 if (!tcp_disconnect_pending (tc))
206 tc->rst_state = tc->state;
207 vec_add1 (wrk->pending_resets, tc->c_c_index);
208 tcp_disconnect_pending_on (tc);
213 * Handle reset packet
215 * Programs disconnect/reset notification that should be sent
216 * later by calling @ref tcp_handle_disconnects
219 tcp_rcv_rst (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
221 TCP_EVT (TCP_EVT_RST_RCVD, tc);
224 case TCP_STATE_SYN_RCVD:
225 tcp_program_reset_ntf (wrk, tc);
226 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
228 case TCP_STATE_SYN_SENT:
229 /* Do not program ntf because the connection is half-open */
230 tc->rst_state = tc->state;
233 case TCP_STATE_ESTABLISHED:
234 tcp_connection_timers_reset (tc);
235 tcp_cong_recovery_off (tc);
236 tcp_program_reset_ntf (wrk, tc);
237 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
238 tcp_program_cleanup (wrk, tc);
240 case TCP_STATE_CLOSE_WAIT:
241 case TCP_STATE_FIN_WAIT_1:
242 case TCP_STATE_FIN_WAIT_2:
243 case TCP_STATE_CLOSING:
244 case TCP_STATE_LAST_ACK:
245 tcp_connection_timers_reset (tc);
246 tcp_cong_recovery_off (tc);
247 tcp_program_reset_ntf (wrk, tc);
248 /* Make sure we mark the session as closed. In some states we may
249 * be still trying to send data */
250 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
251 tcp_program_cleanup (wrk, tc);
253 case TCP_STATE_CLOSED:
254 case TCP_STATE_TIME_WAIT:
257 TCP_DBG ("reset state: %u", tc->state);
262 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
264 * It first verifies if segment has a wrapped sequence number (PAWS) and then
265 * does the processing associated to the first four steps (ignoring security
266 * and precedence): sequence number, rst bit and syn bit checks.
268 * @return 0 if segments passes validation.
271 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
272 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
274 /* We could get a burst of RSTs interleaved with acks */
275 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
277 tcp_send_reset (tc0);
278 *error0 = TCP_ERROR_CONNECTION_CLOSED;
282 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
284 *error0 = TCP_ERROR_SEGMENT_INVALID;
288 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
290 *error0 = TCP_ERROR_OPTIONS;
294 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
296 *error0 = TCP_ERROR_PAWS;
297 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
298 vnet_buffer (b0)->tcp.seq_end);
300 /* If it just so happens that a segment updates tsval_recent for a
301 * segment over 24 days old, invalidate tsval_recent. */
302 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
303 tcp_time_tstamp (tc0->c_thread_index)))
305 tc0->tsval_recent = tc0->rcv_opts.tsval;
306 clib_warning ("paws failed: 24-day old segment");
308 /* Drop after ack if not rst. Resets can fail paws check as per
309 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
310 * be subjected to the PAWS check by verifying an acceptable value in
312 else if (!tcp_rst (th0))
314 tcp_program_ack (tc0);
315 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
320 /* 1st: check sequence number */
321 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
322 vnet_buffer (b0)->tcp.seq_end))
324 /* SYN/SYN-ACK retransmit */
326 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
328 tcp_options_parse (th0, &tc0->rcv_opts, 1);
329 if (tc0->state == TCP_STATE_SYN_RCVD)
331 tcp_send_synack (tc0);
332 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
333 *error0 = TCP_ERROR_SYNS_RCVD;
337 tcp_program_ack (tc0);
338 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
339 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
344 /* If our window is 0 and the packet is in sequence, let it pass
345 * through for ack processing. It should be dropped later. */
346 if (tc0->rcv_wnd < tc0->snd_mss
347 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
350 /* If we entered recovery and peer did so as well, there's a chance that
351 * dup acks won't be acceptable on either end because seq_end may be less
352 * than rcv_las. This can happen if acks are lost in both directions. */
353 if (tcp_in_recovery (tc0)
354 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
355 tc0->rcv_las - tc0->rcv_wnd)
356 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
357 tc0->rcv_nxt + tc0->rcv_wnd))
360 *error0 = TCP_ERROR_RCV_WND;
362 /* If we advertised a zero rcv_wnd and the segment is in the past or the
363 * next one that we expect, it is probably a window probe */
364 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
365 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
366 tc0->rcv_las + tc0->rcv_opts.mss))
367 *error0 = TCP_ERROR_ZERO_RWND;
369 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
372 /* If not RST, send dup ack */
375 tcp_program_dupack (tc0);
376 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
384 /* 2nd: check the RST bit */
385 if (PREDICT_FALSE (tcp_rst (th0)))
387 tcp_rcv_rst (wrk, tc0);
388 *error0 = TCP_ERROR_RST_RCVD;
392 /* 3rd: check security and precedence (skip) */
394 /* 4th: check the SYN bit (in window) */
395 if (PREDICT_FALSE (tcp_syn (th0)))
397 /* As per RFC5961 send challenge ack instead of reset */
398 tcp_program_ack (tc0);
399 *error0 = TCP_ERROR_SPURIOUS_SYN;
403 /* If segment in window, save timestamp */
404 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
405 vnet_buffer (b0)->tcp.seq_end);
413 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
415 /* SND.UNA =< SEG.ACK =< SND.NXT */
416 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
417 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
419 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
420 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
422 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
425 *error = TCP_ERROR_ACK_INVALID;
430 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
431 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
432 *error = TCP_ERROR_ACK_OK;
437 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
439 * Note that although in the original article srtt and rttvar are scaled
440 * to minimize round-off errors, here we don't. Instead, we rely on
441 * better precision time measurements.
443 * A known limitation of the algorithm is that a drop in rtt results in a
444 * rttvar increase and bigger RTO.
446 * mrtt must be provided in @ref TCP_TICK multiples, i.e., in us. Note that
447 * timestamps are measured as ms ticks so they must be converted before
448 * calling this function.
451 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
455 err = mrtt - tc->srtt;
456 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
457 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
458 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
462 tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
464 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
468 * Update rtt estimate
470 * We have potentially three sources of rtt measurements:
472 * TSOPT difference between current and echoed timestamp. It has ms
473 * precision and can be computed per ack
474 * ACK timing one sequence number is tracked per rtt with us (micro second)
476 * rate sample if enabled, all outstanding bytes are tracked with us
477 * precision. Every ack and sack are a rtt sample
479 * Middle boxes are known to fiddle with TCP options so we give higher
480 * priority to ACK timing.
482 * For now, rate sample rtts are only used under congestion.
485 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
489 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
490 * RTT because they're ambiguous. */
491 if (tcp_in_cong_recovery (tc))
493 /* Accept rtt estimates for samples that have not been retransmitted */
494 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
495 || (rs->flags & TCP_BTS_IS_RXT))
498 tcp_estimate_rtt_us (tc, rs->rtt_time);
499 mrtt = rs->rtt_time * THZ;
503 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
505 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
506 tcp_estimate_rtt_us (tc, sample);
507 mrtt = clib_max ((u32) (sample * THZ), 1);
508 /* Allow measuring of a new RTT */
511 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
512 * snd_una, i.e., the left side of the send window:
513 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
514 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
516 mrtt = clib_max (tcp_tstamp (tc) - tc->rcv_opts.tsecr, 1);
517 mrtt *= TCP_TSTP_TO_HZ;
522 /* Ignore dubious measurements */
523 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
526 tcp_estimate_rtt (tc, mrtt);
530 /* If we got here something must've been ACKed so make sure boff is 0,
531 * even if mrtt is not valid since we update the rto lower */
539 tcp_estimate_initial_rtt (tcp_connection_t * tc)
541 u8 thread_index = vlib_num_workers ()? 1 : 0;
546 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
547 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
548 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
553 mrtt = tcp_tstamp (tc) - tc->rcv_opts.tsecr;
554 mrtt = clib_max (mrtt, 1) * TCP_TSTP_TO_HZ;
555 /* Due to retransmits we don't know the initial mrtt */
556 if (tc->rto_boff && mrtt > 1 * THZ)
558 tc->mrtt_us = (f64) mrtt *TCP_TICK;
561 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
563 /* First measurement as per RFC 6298 */
565 tc->rttvar = mrtt >> 1;
571 * Dequeue bytes for connections that have received acks in last burst
574 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
576 u32 thread_index = wrk->vm->thread_index;
577 u32 *pending_deq_acked;
578 tcp_connection_t *tc;
581 if (!vec_len (wrk->pending_deq_acked))
584 pending_deq_acked = wrk->pending_deq_acked;
585 for (i = 0; i < vec_len (pending_deq_acked); i++)
587 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
588 tc->flags &= ~TCP_CONN_DEQ_PENDING;
590 if (PREDICT_FALSE (!tc->burst_acked))
593 /* Dequeue the newly ACKed bytes */
594 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
595 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
597 if (tcp_is_descheduled (tc))
600 /* If everything has been acked, stop retransmit timer
601 * otherwise update. */
602 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
604 /* Update pacer based on our new cwnd estimate */
605 tcp_connection_tx_pacer_update (tc);
609 vec_set_len (wrk->pending_deq_acked, 0);
613 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
615 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
617 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
618 tc->flags |= TCP_CONN_DEQ_PENDING;
620 tc->burst_acked += tc->bytes_acked;
624 * Try to update snd_wnd based on feedback received from peer.
626 * If successful, and new window is 'effectively' 0, activate persist
630 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
632 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
633 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
634 if (seq_lt (tc->snd_wl1, seq)
635 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
637 tc->snd_wnd = snd_wnd;
640 TCP_EVT (TCP_EVT_SND_WND, tc);
642 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
644 if (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
646 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
648 /* Set persist timer if we just got 0 wnd. If already set,
649 * update it because some data sent with snd_wnd < snd_mss was
651 if (tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
652 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
653 tcp_persist_timer_set (&wrk->timer_wheel, tc);
658 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
660 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
661 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
664 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
667 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
677 * Init loss recovery/fast recovery.
679 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
680 * updated in @ref tcp_cc_handle_event after fast retransmit
683 tcp_cc_init_congestion (tcp_connection_t * tc)
685 tcp_fastrecovery_on (tc);
686 tc->snd_congestion = tc->snd_nxt;
687 tc->cwnd_acc_bytes = 0;
688 tc->snd_rxt_bytes = 0;
689 tc->rxt_delivered = 0;
690 tc->prr_delivered = 0;
691 tc->prr_start = tc->snd_una;
692 tc->prev_ssthresh = tc->ssthresh;
693 tc->prev_cwnd = tc->cwnd;
695 tc->snd_rxt_ts = tcp_tstamp (tc);
696 tcp_cc_congestion (tc);
698 /* Post retransmit update cwnd to ssthresh and account for the
699 * three segments that have left the network and should've been
700 * buffered at the receiver XXX */
701 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
702 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
704 tc->fr_occurences += 1;
705 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
709 tcp_cc_congestion_undo (tcp_connection_t * tc)
711 tc->cwnd = tc->prev_cwnd;
712 tc->ssthresh = tc->prev_ssthresh;
713 tcp_cc_undo_recovery (tc);
714 ASSERT (tc->rto_boff == 0);
715 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
719 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
721 return (tcp_in_recovery (tc) && tc->rto_boff == 1
723 && tcp_opts_tstamp (&tc->rcv_opts)
724 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
728 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
730 return (tcp_cc_is_spurious_timeout_rxt (tc));
734 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
738 /* If of of the two conditions lower hold, reset dupacks because
739 * we're probably after timeout (RFC6582 heuristics).
740 * If Cumulative ack does not cover more than congestion threshold,
742 * 1) The following doesn't hold: The congestion window is greater
743 * than SMSS bytes and the difference between highest_ack
744 * and prev_highest_ack is at most 4*SMSS bytes
745 * 2) Echoed timestamp in the last non-dup ack does not equal the
748 if (seq_leq (tc->snd_una, tc->snd_congestion)
749 && ((!(tc->cwnd > tc->snd_mss
750 && tc->bytes_acked <= 4 * tc->snd_mss))
751 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
757 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
761 tcp_cc_try_recover (tcp_connection_t *tc)
763 sack_scoreboard_hole_t *hole;
766 ASSERT (tcp_in_cong_recovery (tc));
768 if (tcp_cc_is_spurious_retransmit (tc))
770 tcp_cc_congestion_undo (tc);
774 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
776 tcp_recovery_off (tc);
778 /* Previous recovery left us congested. Continue sending as part
779 * of the current recovery event with an updated snd_congestion */
780 if (tc->sack_sb.sacked_bytes && tcp_in_fastrecovery (tc))
782 tc->snd_congestion = tc->snd_nxt;
786 tc->rxt_delivered = 0;
787 tc->snd_rxt_bytes = 0;
789 tc->prr_delivered = 0;
791 tc->flags &= ~TCP_CONN_RXT_PENDING;
793 hole = scoreboard_first_hole (&tc->sack_sb);
794 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
795 scoreboard_clear (&tc->sack_sb);
797 if (tcp_in_fastrecovery (tc) && !is_spurious)
798 tcp_cc_recovered (tc);
800 tcp_fastrecovery_off (tc);
801 tcp_fastrecovery_first_off (tc);
802 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
804 ASSERT (tc->rto_boff == 0);
805 ASSERT (!tcp_in_cong_recovery (tc));
806 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
812 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
814 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
816 /* Congestion avoidance */
817 tcp_cc_rcv_ack (tc, rs);
819 /* If a cumulative ack, make sure dupacks is 0 */
824 * One function to rule them all ... and in the darkness bind them
827 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
830 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
832 /* If reneging, wait for timer based retransmits */
833 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
837 * If not in recovery, figure out if we should enter
839 if (!tcp_in_cong_recovery (tc))
844 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
845 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
847 if (tcp_should_fastrecover (tc, has_sack))
849 tcp_cc_init_congestion (tc);
852 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
854 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
855 tcp_program_retransmit (tc);
862 * Already in recovery
866 * See if we can exit and stop retransmitting
868 if (seq_geq (tc->snd_una, tc->snd_congestion))
870 /* If successfully recovered, treat ack as congestion avoidance ack
871 * and return. Otherwise, we're still congested so process feedback */
872 if (!tcp_cc_try_recover (tc))
874 tcp_cc_rcv_ack (tc, rs);
880 * Process (re)transmit feedback. Output path uses this to decide how much
881 * more data to release into the network
885 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
886 tcp_fastrecovery_first_on (tc);
888 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
889 tc->prr_delivered += rs->delivered;
895 tc->rcv_dupacks += 1;
896 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
898 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
901 tc->prr_delivered += clib_min (tc->snd_mss,
902 tc->snd_nxt - tc->snd_una);
904 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
908 /* If partial ack, assume that the first un-acked segment was lost */
909 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
910 tcp_fastrecovery_first_on (tc);
913 tcp_program_retransmit (tc);
916 * Notify cc of the event
919 if (!tc->bytes_acked)
921 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
925 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
926 * reset dupacks to 0. Also needed if in congestion recovery */
929 if (tcp_in_recovery (tc))
930 tcp_cc_rcv_ack (tc, rs);
932 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
936 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
938 if (!tcp_in_cong_recovery (tc))
941 if (tcp_opts_sack_permitted (&tc->rcv_opts))
942 tcp_rcv_sacks (tc, tc->snd_una);
946 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
947 tcp_bt_sample_delivery_rate (tc, rs);
949 tcp_cc_handle_event (tc, rs, 1);
953 * Check if duplicate ack as per RFC5681 Sec. 2
956 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
959 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
960 && seq_gt (tc->snd_nxt, tc->snd_una)
961 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
962 && (prev_snd_wnd == tc->snd_wnd));
966 * Checks if ack is a congestion control event.
969 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
970 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
972 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
973 * defined to be 'duplicate' as well */
974 *is_dack = tc->sack_sb.last_sacked_bytes
975 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
977 return (*is_dack || tcp_in_cong_recovery (tc));
981 * Process incoming ACK
984 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
985 tcp_header_t * th, u32 * error)
987 u32 prev_snd_wnd, prev_snd_una;
988 tcp_rate_sample_t rs = { 0 };
991 TCP_EVT (TCP_EVT_CC_STAT, tc);
993 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
994 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
996 /* We've probably entered recovery and the peer still has some
997 * of the data we've sent. Update snd_nxt and accept the ack */
998 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)
999 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1001 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1005 tc->errors.above_ack_wnd += 1;
1006 *error = TCP_ERROR_ACK_FUTURE;
1007 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1011 /* If old ACK, probably it's an old dupack */
1012 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1014 tc->errors.below_ack_wnd += 1;
1015 *error = TCP_ERROR_ACK_OLD;
1016 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1018 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1021 tcp_handle_old_ack (tc, &rs);
1023 /* Don't drop yet */
1030 * Looks okay, process feedback
1033 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1034 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1036 prev_snd_wnd = tc->snd_wnd;
1037 prev_snd_una = tc->snd_una;
1038 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1039 vnet_buffer (b)->tcp.ack_number,
1040 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1041 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1042 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1043 tcp_validate_txf_size (tc, tc->bytes_acked);
1045 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1046 tcp_bt_sample_delivery_rate (tc, &rs);
1048 rs.delivered = tc->bytes_acked + tc->sack_sb.last_sacked_bytes -
1049 tc->sack_sb.last_bytes_delivered;
1051 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
1053 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1054 if (tc->bytes_acked)
1055 tcp_program_dequeue (wrk, tc);
1058 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1061 * Check if we have congestion event
1064 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1066 tcp_cc_handle_event (tc, &rs, is_dack);
1067 tc->dupacks_in += is_dack;
1068 if (!tcp_in_cong_recovery (tc))
1070 *error = TCP_ERROR_ACK_OK;
1073 *error = TCP_ERROR_ACK_DUP;
1074 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1080 * Update congestion control (slow start/congestion avoidance)
1082 tcp_cc_update (tc, &rs);
1083 *error = TCP_ERROR_ACK_OK;
1088 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1090 if (!tcp_disconnect_pending (tc))
1092 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1093 tcp_disconnect_pending_on (tc);
1098 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1100 u32 thread_index, *pending_disconnects, *pending_resets;
1101 tcp_connection_t *tc;
1104 if (vec_len (wrk->pending_disconnects))
1106 thread_index = wrk->vm->thread_index;
1107 pending_disconnects = wrk->pending_disconnects;
1108 for (i = 0; i < vec_len (pending_disconnects); i++)
1110 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1111 tcp_disconnect_pending_off (tc);
1112 session_transport_closing_notify (&tc->connection);
1114 vec_set_len (wrk->pending_disconnects, 0);
1117 if (vec_len (wrk->pending_resets))
1119 thread_index = wrk->vm->thread_index;
1120 pending_resets = wrk->pending_resets;
1121 for (i = 0; i < vec_len (pending_resets); i++)
1123 tc = tcp_connection_get (pending_resets[i], thread_index);
1124 tcp_disconnect_pending_off (tc);
1125 tcp_handle_rst (tc);
1127 vec_set_len (wrk->pending_resets, 0);
1132 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1135 /* Reject out-of-order fins */
1136 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1139 /* Account for the FIN and send ack */
1141 tc->flags |= TCP_CONN_FINRCVD;
1142 tcp_program_ack (tc);
1143 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1144 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1145 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1146 tcp_program_disconnect (wrk, tc);
1147 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1148 tcp_cfg.closewait_time);
1149 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1150 *error = TCP_ERROR_FIN_RCVD;
1153 /** Enqueue data for delivery to application */
1155 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1158 int written, error = TCP_ERROR_ENQUEUED;
1160 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1162 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1163 1 /* queue event */ , 1);
1165 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1167 /* Update rcv_nxt */
1168 if (PREDICT_TRUE (written == data_len))
1170 tc->rcv_nxt += written;
1171 tc->bytes_in += written;
1173 /* If more data written than expected, account for out-of-order bytes. */
1174 else if (written > data_len)
1176 tc->rcv_nxt += written;
1177 tc->bytes_in += data_len;
1178 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1180 else if (written > 0)
1182 /* We've written something but FIFO is probably full now */
1183 tc->rcv_nxt += written;
1184 tc->bytes_in += written;
1185 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1189 /* Packet made it through for ack processing */
1190 if (tc->rcv_wnd < tc->snd_mss)
1191 return TCP_ERROR_ZERO_RWND;
1193 return TCP_ERROR_FIFO_FULL;
1196 /* Update SACK list if need be */
1197 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
1199 /* Remove SACK blocks that have been delivered */
1200 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1206 /** Enqueue out-of-order data */
1208 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1214 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1217 /* Enqueue out-of-order data with relative offset */
1218 rv = session_enqueue_stream_connection (&tc->connection, b,
1219 vnet_buffer (b)->tcp.seq_number -
1220 tc->rcv_nxt, 0 /* queue event */ ,
1223 /* Nothing written */
1226 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1227 return TCP_ERROR_FIFO_FULL;
1230 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1231 tc->bytes_in += data_len;
1233 /* Update SACK list if in use */
1234 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1236 ooo_segment_t *newest;
1239 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1241 /* Get the newest segment from the fifo */
1242 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1245 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1246 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1247 start = tc->rcv_nxt + offset;
1248 end = start + ooo_segment_length (s0->rx_fifo, newest);
1249 tcp_update_sack_list (tc, start, end);
1250 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1251 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1255 return TCP_ERROR_ENQUEUED_OOO;
1259 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1261 u32 discard, first = b->current_length;
1262 vlib_main_t *vm = vlib_get_main ();
1264 /* Handle multi-buffer segments */
1265 if (n_bytes_to_drop > b->current_length)
1267 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1271 discard = clib_min (n_bytes_to_drop, b->current_length);
1272 vlib_buffer_advance (b, discard);
1273 b = vlib_get_buffer (vm, b->next_buffer);
1274 n_bytes_to_drop -= discard;
1276 while (n_bytes_to_drop);
1277 if (n_bytes_to_drop > first)
1278 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1281 vlib_buffer_advance (b, n_bytes_to_drop);
1282 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1287 * Receive buffer for connection and handle acks
1289 * It handles both in order or out-of-order data.
1292 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1295 u32 error, n_bytes_to_drop, n_data_bytes;
1297 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1298 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1299 ASSERT (n_data_bytes);
1300 tc->data_segs_in += 1;
1302 /* Make sure we don't consume trailing bytes */
1303 if (PREDICT_FALSE (b->current_length > n_data_bytes))
1304 b->current_length = n_data_bytes;
1306 /* Handle out-of-order data */
1307 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1309 /* Old sequence numbers allowed through because they overlapped
1311 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1313 /* Completely in the past (possible retransmit). Ack
1314 * retransmissions since we may not have any data to send */
1315 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1317 tcp_program_dupack (tc);
1318 tc->errors.below_data_wnd++;
1319 error = TCP_ERROR_SEGMENT_OLD;
1323 /* Chop off the bytes in the past and see if what is left
1324 * can be enqueued in order */
1325 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1326 n_data_bytes -= n_bytes_to_drop;
1327 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1328 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1330 error = TCP_ERROR_SEGMENT_OLD;
1336 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1337 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1338 tcp_program_dupack (tc);
1339 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1340 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1341 tc->rcv_las + tc->rcv_wnd);
1347 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1348 * segments can be enqueued after fifo tail offset changes. */
1349 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1350 tcp_program_ack (tc);
1358 tcp_header_t tcp_header;
1359 tcp_connection_t tcp_connection;
1363 format_tcp_rx_trace (u8 * s, va_list * args)
1365 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1366 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1367 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1368 tcp_connection_t *tc = &t->tcp_connection;
1369 u32 indent = format_get_indent (s);
1371 if (!tc->c_lcl_port)
1372 s = format (s, "no tcp connection\n%U%U", format_white_space, indent,
1373 format_tcp_header, &t->tcp_header, 128);
1375 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1376 format_tcp_state, tc->state, format_white_space, indent,
1377 format_tcp_header, &t->tcp_header, 128);
1383 format_tcp_rx_trace_short (u8 * s, va_list * args)
1385 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1386 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1387 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1389 s = format (s, "%d -> %d (%U)",
1390 clib_net_to_host_u16 (t->tcp_header.dst_port),
1391 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1392 t->tcp_connection.state);
1398 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1399 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1403 clib_memcpy_fast (&t0->tcp_connection, tc0,
1404 sizeof (t0->tcp_connection));
1408 th0 = tcp_buffer_hdr (b0);
1410 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1414 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1415 vlib_frame_t * frame, u8 is_ip4)
1419 n_left = frame->n_vectors;
1420 from = vlib_frame_vector_args (frame);
1424 tcp_connection_t *tc0;
1431 b0 = vlib_get_buffer (vm, bi0);
1433 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1435 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1436 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1438 th0 = tcp_buffer_hdr (b0);
1439 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1448 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1449 vlib_frame_t * frame, int is_ip4)
1451 u32 thread_index = vm->thread_index, errors = 0;
1452 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1453 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1454 u16 err_counters[TCP_N_ERROR] = { 0 };
1455 u32 n_left_from, *from;
1457 if (node->flags & VLIB_NODE_FLAG_TRACE)
1458 tcp_established_trace_frame (vm, node, frame, is_ip4);
1460 from = vlib_frame_vector_args (frame);
1461 n_left_from = frame->n_vectors;
1463 vlib_get_buffers (vm, from, bufs, n_left_from);
1466 while (n_left_from > 0)
1468 u32 error = TCP_ERROR_ACK_OK;
1469 tcp_connection_t *tc;
1472 if (n_left_from > 1)
1474 vlib_prefetch_buffer_header (b[1], LOAD);
1475 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
1478 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1481 if (PREDICT_FALSE (tc == 0))
1483 error = TCP_ERROR_INVALID_CONNECTION;
1487 th = tcp_buffer_hdr (b[0]);
1489 /* TODO header prediction fast path */
1491 /* 1-4: check SEQ, RST, SYN */
1492 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
1494 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
1498 /* 5: check the ACK field */
1499 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
1502 /* 6: check the URG bit TODO */
1504 /* 7: process the segment text */
1505 if (vnet_buffer (b[0])->tcp.data_len)
1506 error = tcp_segment_rcv (wrk, tc, b[0]);
1508 /* 8: check the FIN bit */
1509 if (PREDICT_FALSE (tcp_is_fin (th)))
1510 tcp_rcv_fin (wrk, tc, b[0], &error);
1513 tcp_inc_err_counter (err_counters, error, 1);
1519 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
1521 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
1522 tcp_store_err_counters (established, err_counters);
1523 tcp_handle_postponed_dequeues (wrk);
1524 tcp_handle_disconnects (wrk);
1525 vlib_buffer_free (vm, from, frame->n_vectors);
1527 return frame->n_vectors;
1530 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1531 vlib_node_runtime_t * node,
1532 vlib_frame_t * from_frame)
1534 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1537 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1538 vlib_node_runtime_t * node,
1539 vlib_frame_t * from_frame)
1541 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1545 VLIB_REGISTER_NODE (tcp4_established_node) =
1547 .name = "tcp4-established",
1548 /* Takes a vector of packets. */
1549 .vector_size = sizeof (u32),
1550 .n_errors = TCP_N_ERROR,
1551 .error_counters = tcp_input_error_counters,
1552 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1555 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1556 foreach_tcp_state_next
1559 .format_trace = format_tcp_rx_trace_short,
1564 VLIB_REGISTER_NODE (tcp6_established_node) =
1566 .name = "tcp6-established",
1567 /* Takes a vector of packets. */
1568 .vector_size = sizeof (u32),
1569 .n_errors = TCP_N_ERROR,
1570 .error_counters = tcp_input_error_counters,
1571 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1574 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1575 foreach_tcp_state_next
1578 .format_trace = format_tcp_rx_trace_short,
1584 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1587 transport_connection_t *tmp = 0;
1594 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1597 u8 is_ip_valid = 0, val_l, val_r;
1599 if (tc->connection.is_ip4)
1601 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
1603 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1604 &tc->connection.lcl_ip.ip4);
1605 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1606 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1607 &tc->connection.rmt_ip.ip4);
1608 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1609 is_ip_valid = val_l && val_r;
1613 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
1615 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1616 &tc->connection.lcl_ip.ip6);
1617 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1618 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1619 &tc->connection.rmt_ip.ip6);
1620 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1621 is_ip_valid = val_l && val_r;
1624 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1625 && (tc->state == TCP_STATE_LISTEN
1626 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
1630 handle = session_lookup_half_open_handle (&tc->connection);
1631 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
1632 tc->c_proto, tc->c_is_ip4);
1636 if (tmp->lcl_port == hdr->dst_port
1637 && tmp->rmt_port == hdr->src_port)
1639 TCP_DBG ("half-open is valid!");
1648 * Lookup transport connection
1650 static tcp_connection_t *
1651 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1655 transport_connection_t *tconn;
1656 tcp_connection_t *tc;
1661 ip4 = vlib_buffer_get_current (b);
1662 tcp = ip4_next_header (ip4);
1663 tconn = session_lookup_connection_wt4 (fib_index,
1668 TRANSPORT_PROTO_TCP,
1669 thread_index, &is_filtered);
1670 tc = tcp_get_connection_from_transport (tconn);
1671 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1676 ip6 = vlib_buffer_get_current (b);
1677 tcp = ip6_next_header (ip6);
1678 tconn = session_lookup_connection_wt6 (fib_index,
1683 TRANSPORT_PROTO_TCP,
1684 thread_index, &is_filtered);
1685 tc = tcp_get_connection_from_transport (tconn);
1686 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
1691 static tcp_connection_t *
1692 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1698 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1699 tcp_header_t *tcp = tcp_buffer_hdr (b);
1700 s = session_lookup_listener4 (fib_index,
1702 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1706 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1707 tcp_header_t *tcp = tcp_buffer_hdr (b);
1708 s = session_lookup_listener6 (fib_index,
1710 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1713 if (PREDICT_TRUE (s != 0))
1714 return tcp_get_connection_from_transport (transport_get_listener
1715 (TRANSPORT_PROTO_TCP,
1716 s->connection_index));
1722 tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1723 u32 *from, u32 n_bufs)
1725 tcp_connection_t *tc = 0;
1730 for (i = 0; i < n_bufs; i++)
1732 b = vlib_get_buffer (vm, from[i]);
1733 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1736 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1737 t = vlib_add_trace (vm, node, b, sizeof (*t));
1738 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1743 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1745 vnet_main_t *vnm = vnet_get_main ();
1746 const dpo_id_t *dpo;
1747 const load_balance_t *lb;
1748 vnet_hw_interface_t *hw_if;
1749 u32 sw_if_idx, lb_idx;
1753 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1754 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1758 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1759 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1762 lb = load_balance_get (lb_idx);
1763 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1765 dpo = load_balance_get_bucket_i (lb, 0);
1767 sw_if_idx = dpo_get_urpf (dpo);
1768 if (PREDICT_FALSE (sw_if_idx == ~0))
1771 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
1772 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
1773 tc->cfg_flags |= TCP_CFG_F_TSO;
1777 tcp_input_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1778 vlib_buffer_t **bs, u16 *nexts, u32 n_bufs, u8 is_ip4)
1780 tcp_connection_t *tc;
1786 for (i = 0; i < n_bufs; i++)
1788 if (!(bs[i]->flags & VLIB_BUFFER_IS_TRACED))
1791 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
1792 if (nexts[i] == TCP_INPUT_NEXT_DROP || nexts[i] == TCP_INPUT_NEXT_PUNT ||
1793 nexts[i] == TCP_INPUT_NEXT_RESET)
1799 flags = vnet_buffer (bs[i])->tcp.flags;
1801 if (flags == TCP_STATE_LISTEN)
1802 tc = tcp_listener_get (vnet_buffer (bs[i])->tcp.connection_index);
1803 else if (flags == TCP_STATE_SYN_SENT)
1804 tc = tcp_half_open_connection_get (
1805 vnet_buffer (bs[i])->tcp.connection_index);
1807 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
1810 tcp = tcp_buffer_hdr (bs[i]);
1811 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
1816 tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1817 vlib_frame_t *frame, int is_ip4)
1819 u32 n_left_from, *from, thread_index = vm->thread_index, errors = 0;
1820 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1821 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1823 from = vlib_frame_vector_args (frame);
1824 n_left_from = frame->n_vectors;
1826 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1827 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1829 vlib_get_buffers (vm, from, bufs, n_left_from);
1832 while (n_left_from > 0)
1834 u32 ack, seq, error = TCP_ERROR_NONE;
1835 tcp_connection_t *tc, *new_tc;
1838 tc = tcp_half_open_connection_get (
1839 vnet_buffer (b[0])->tcp.connection_index);
1840 if (PREDICT_FALSE (tc == 0))
1842 error = TCP_ERROR_INVALID_CONNECTION;
1846 /* Half-open completed or cancelled recently but the connection
1847 * was't removed yet by the owning thread */
1848 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
1850 error = TCP_ERROR_SPURIOUS_SYN_ACK;
1854 ack = vnet_buffer (b[0])->tcp.ack_number;
1855 seq = vnet_buffer (b[0])->tcp.seq_number;
1856 tcp = tcp_buffer_hdr (b[0]);
1858 /* Crude check to see if the connection handle does not match
1859 * the packet. Probably connection just switched to established */
1860 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1861 tcp->src_port != tc->c_rmt_port))
1863 error = TCP_ERROR_INVALID_CONNECTION;
1867 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
1869 error = TCP_ERROR_SEGMENT_INVALID;
1873 /* SYNs consume sequence numbers */
1874 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
1877 * 1. check the ACK bit
1881 * If the ACK bit is set
1882 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1883 * the RST bit is set, if so drop the segment and return)
1884 * <SEQ=SEG.ACK><CTL=RST>
1885 * and discard the segment. Return.
1886 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1890 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
1893 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1894 error = TCP_ERROR_RCV_WND;
1898 /* Make sure ACK is valid */
1899 if (seq_gt (tc->snd_una, ack))
1901 error = TCP_ERROR_ACK_INVALID;
1907 * 2. check the RST bit
1912 /* If ACK is acceptable, signal client that peer is not
1913 * willing to accept connection and drop connection*/
1915 tcp_rcv_rst (wrk, tc);
1916 error = TCP_ERROR_RST_RCVD;
1921 * 3. check the security and precedence (skipped)
1925 * 4. check the SYN bit
1928 /* No SYN flag. Drop. */
1931 error = TCP_ERROR_SEGMENT_INVALID;
1936 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
1938 error = TCP_ERROR_OPTIONS;
1942 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1943 * current thread pool. */
1944 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
1945 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1947 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1949 if (tcp_opts_tstamp (&new_tc->rcv_opts))
1951 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1952 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
1955 if (tcp_opts_wscale (&new_tc->rcv_opts))
1956 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
1958 new_tc->rcv_wscale = 0;
1960 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1961 << new_tc->snd_wscale;
1962 new_tc->snd_wl1 = seq;
1963 new_tc->snd_wl2 = ack;
1965 tcp_connection_init_vars (new_tc);
1967 /* SYN-ACK: See if we can switch to ESTABLISHED state */
1968 if (PREDICT_TRUE (tcp_ack (tcp)))
1970 /* Our SYN is ACKed: we have iss < ack = snd_una */
1972 /* TODO Dequeue acknowledged segments if we support Fast Open */
1973 new_tc->snd_una = ack;
1974 new_tc->state = TCP_STATE_ESTABLISHED;
1976 /* Make sure las is initialized for the wnd computation */
1977 new_tc->rcv_las = new_tc->rcv_nxt;
1979 /* Notify app that we have connection. If session layer can't
1980 * allocate session send reset */
1981 if (session_stream_connect_notify (&new_tc->connection,
1984 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
1985 tcp_connection_cleanup (new_tc);
1986 error = TCP_ERROR_CREATE_SESSION_FAIL;
1990 transport_fifos_init_ooo (&new_tc->connection);
1991 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1992 /* Update rtt with the syn-ack sample */
1993 tcp_estimate_initial_rtt (new_tc);
1994 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1995 error = TCP_ERROR_SYN_ACKS_RCVD;
1997 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2000 new_tc->state = TCP_STATE_SYN_RCVD;
2002 /* Notify app that we have connection */
2003 if (session_stream_connect_notify (&new_tc->connection,
2006 tcp_connection_cleanup (new_tc);
2007 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2008 TCP_EVT (TCP_EVT_RST_SENT, tc);
2009 error = TCP_ERROR_CREATE_SESSION_FAIL;
2013 transport_fifos_init_ooo (&new_tc->connection);
2014 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
2016 tcp_init_snd_vars (new_tc);
2017 tcp_send_synack (new_tc);
2018 error = TCP_ERROR_SYNS_RCVD;
2022 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
2023 tcp_check_tx_offload (new_tc, is_ip4);
2025 /* Read data, if any */
2026 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
2028 clib_warning ("rcvd data in syn-sent");
2029 error = tcp_segment_rcv (wrk, new_tc, b[0]);
2030 if (error == TCP_ERROR_ACK_OK)
2031 error = TCP_ERROR_SYN_ACKS_RCVD;
2035 /* Send ack now instead of programming it because connection was
2036 * just established and it's not optional. */
2037 tcp_send_ack (new_tc);
2042 /* If this is not the owning thread, wait for syn retransmit to
2043 * expire and cleanup then */
2044 if (tcp_half_open_connection_cleanup (tc))
2045 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
2051 tcp_inc_counter (syn_sent, error, 1);
2055 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
2056 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2057 vlib_buffer_free (vm, from, frame->n_vectors);
2058 tcp_handle_disconnects (wrk);
2060 return frame->n_vectors;
2063 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2064 vlib_node_runtime_t * node,
2065 vlib_frame_t * from_frame)
2067 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2070 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2071 vlib_node_runtime_t * node,
2072 vlib_frame_t * from_frame)
2074 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2078 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2080 .name = "tcp4-syn-sent",
2081 /* Takes a vector of packets. */
2082 .vector_size = sizeof (u32),
2083 .n_errors = TCP_N_ERROR,
2084 .error_counters = tcp_input_error_counters,
2085 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2088 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2089 foreach_tcp_state_next
2092 .format_trace = format_tcp_rx_trace_short,
2097 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2099 .name = "tcp6-syn-sent",
2100 /* Takes a vector of packets. */
2101 .vector_size = sizeof (u32),
2102 .n_errors = TCP_N_ERROR,
2103 .error_counters = tcp_input_error_counters,
2104 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2107 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2108 foreach_tcp_state_next
2111 .format_trace = format_tcp_rx_trace_short,
2116 tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2117 u32 *from, u32 n_bufs)
2119 u32 thread_index = vm->thread_index;
2120 tcp_connection_t *tc = 0;
2125 for (i = 0; i < n_bufs; i++)
2127 b = vlib_get_buffer (vm, from[i]);
2128 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2130 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2132 t = vlib_add_trace (vm, node, b, sizeof (*t));
2133 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2138 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2139 * as per RFC793 p. 64
2142 tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2143 vlib_frame_t *frame, int is_ip4)
2145 u32 thread_index = vm->thread_index, errors, n_left_from, *from, max_deq;
2146 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2147 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2149 from = vlib_frame_vector_args (frame);
2150 n_left_from = frame->n_vectors;
2152 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2153 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2155 vlib_get_buffers (vm, from, bufs, n_left_from);
2158 while (n_left_from > 0)
2160 u32 error = TCP_ERROR_NONE;
2161 tcp_header_t *tcp = 0;
2162 tcp_connection_t *tc;
2165 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2167 if (PREDICT_FALSE (tc == 0))
2169 error = TCP_ERROR_INVALID_CONNECTION;
2173 tcp = tcp_buffer_hdr (b[0]);
2174 is_fin = tcp_is_fin (tcp);
2178 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2180 tcp_connection_t *tmp;
2181 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
2183 if (tmp->state != tc->state)
2185 if (tc->state != TCP_STATE_CLOSED)
2186 clib_warning ("state changed");
2193 * Special treatment for CLOSED
2195 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2197 error = TCP_ERROR_CONNECTION_CLOSED;
2202 * For all other states (except LISTEN)
2205 /* 1-4: check SEQ, RST, SYN */
2206 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
2209 /* 5: check the ACK field */
2212 case TCP_STATE_SYN_RCVD:
2214 /* Make sure the segment is exactly right */
2215 if (tc->rcv_nxt != vnet_buffer (b[0])->tcp.seq_number || is_fin)
2217 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2218 error = TCP_ERROR_SEGMENT_INVALID;
2223 * If the segment acknowledgment is not acceptable, form a
2225 * <SEQ=SEG.ACK><CTL=RST>
2228 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2230 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2231 error = TCP_ERROR_SEGMENT_INVALID;
2235 /* Update rtt and rto */
2236 tcp_estimate_initial_rtt (tc);
2237 tcp_connection_tx_pacer_update (tc);
2239 /* Switch state to ESTABLISHED */
2240 tc->state = TCP_STATE_ESTABLISHED;
2241 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
2243 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2244 tcp_check_tx_offload (tc, is_ip4);
2246 /* Initialize session variables */
2247 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2248 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2249 << tc->rcv_opts.wscale;
2250 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2251 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
2253 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2254 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2255 if (session_stream_accept_notify (&tc->connection))
2257 error = TCP_ERROR_MSG_QUEUE_FULL;
2258 tcp_send_reset (tc);
2259 session_transport_delete_notify (&tc->connection);
2260 tcp_connection_cleanup (tc);
2263 error = TCP_ERROR_ACK_OK;
2265 case TCP_STATE_ESTABLISHED:
2266 /* We can get packets in established state here because they
2267 * were enqueued before state change */
2268 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2272 case TCP_STATE_FIN_WAIT_1:
2273 /* In addition to the processing for the ESTABLISHED state, if
2274 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2275 * continue processing in that state. */
2276 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2279 /* Still have to send the FIN */
2280 if (tc->flags & TCP_CONN_FINPNDG)
2282 /* TX fifo finally drained */
2283 max_deq = transport_max_tx_dequeue (&tc->connection);
2284 if (max_deq <= tc->burst_acked)
2286 /* If a fin was received and data was acked extend wait */
2287 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2288 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2289 tcp_cfg.closewait_time);
2291 /* If FIN is ACKed */
2292 else if (tc->snd_una == tc->snd_nxt)
2294 /* Stop all retransmit timers because we have nothing more
2296 tcp_connection_timers_reset (tc);
2298 /* We already have a FIN but didn't transition to CLOSING
2299 * because of outstanding tx data. Close the connection. */
2300 if (tc->flags & TCP_CONN_FINRCVD)
2302 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2303 session_transport_closed_notify (&tc->connection);
2304 tcp_program_cleanup (wrk, tc);
2308 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
2309 /* Enable waitclose because we're willing to wait for peer's
2310 * FIN but not indefinitely. */
2311 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2312 tcp_cfg.finwait2_time);
2314 /* Don't try to deq the FIN acked */
2315 if (tc->burst_acked > 1)
2316 session_tx_fifo_dequeue_drop (&tc->connection,
2317 tc->burst_acked - 1);
2318 tc->burst_acked = 0;
2321 case TCP_STATE_FIN_WAIT_2:
2322 /* In addition to the processing for the ESTABLISHED state, if
2323 * the retransmission queue is empty, the user's CLOSE can be
2324 * acknowledged ("ok") but do not delete the TCB. */
2325 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2327 tc->burst_acked = 0;
2329 case TCP_STATE_CLOSE_WAIT:
2330 /* Do the same processing as for the ESTABLISHED state. */
2331 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
2334 if (!(tc->flags & TCP_CONN_FINPNDG))
2337 /* Still have outstanding tx data */
2338 max_deq = transport_max_tx_dequeue (&tc->connection);
2339 if (max_deq > tc->burst_acked)
2343 tcp_connection_timers_reset (tc);
2344 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2345 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2346 tcp_cfg.lastack_time);
2348 case TCP_STATE_CLOSING:
2349 /* In addition to the processing for the ESTABLISHED state, if
2350 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2351 * otherwise ignore the segment. */
2352 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2355 if (tc->snd_una != tc->snd_nxt)
2358 tcp_connection_timers_reset (tc);
2359 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2360 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2361 tcp_cfg.timewait_time);
2362 session_transport_closed_notify (&tc->connection);
2366 case TCP_STATE_LAST_ACK:
2367 /* The only thing that [should] arrive in this state is an
2368 * acknowledgment of our FIN. If our FIN is now acknowledged,
2369 * delete the TCB, enter the CLOSED state, and return. */
2371 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2374 /* Apparently our ACK for the peer's FIN was lost */
2375 if (is_fin && tc->snd_una != tc->snd_nxt)
2381 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2382 session_transport_closed_notify (&tc->connection);
2384 /* Don't free the connection from the data path since
2385 * we can't ensure that we have no packets already enqueued
2386 * to output. Rely instead on the waitclose timer */
2387 tcp_connection_timers_reset (tc);
2388 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
2393 case TCP_STATE_TIME_WAIT:
2394 /* The only thing that can arrive in this state is a
2395 * retransmission of the remote FIN. Acknowledge it, and restart
2396 * the 2 MSL timeout. */
2398 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
2404 tcp_program_ack (tc);
2405 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2406 tcp_cfg.timewait_time);
2414 /* 6: check the URG bit TODO */
2416 /* 7: process the segment text */
2419 case TCP_STATE_ESTABLISHED:
2420 case TCP_STATE_FIN_WAIT_1:
2421 case TCP_STATE_FIN_WAIT_2:
2422 if (vnet_buffer (b[0])->tcp.data_len)
2423 error = tcp_segment_rcv (wrk, tc, b[0]);
2424 /* Don't accept out of order fins lower */
2425 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
2428 case TCP_STATE_CLOSE_WAIT:
2429 case TCP_STATE_CLOSING:
2430 case TCP_STATE_LAST_ACK:
2431 case TCP_STATE_TIME_WAIT:
2432 /* This should not occur, since a FIN has been received from the
2433 * remote side. Ignore the segment text. */
2437 /* 8: check the FIN bit */
2441 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
2445 case TCP_STATE_ESTABLISHED:
2446 /* Account for the FIN and send ack */
2448 tcp_program_ack (tc);
2449 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2450 tcp_program_disconnect (wrk, tc);
2451 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2452 tcp_cfg.closewait_time);
2454 case TCP_STATE_SYN_RCVD:
2455 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2456 * notified yet, set a cleanup timer instead of relying on
2457 * disconnect notify and the implicit close call. */
2458 tcp_connection_timers_reset (tc);
2461 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2462 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2463 tcp_cfg.lastack_time);
2465 case TCP_STATE_CLOSE_WAIT:
2466 case TCP_STATE_CLOSING:
2467 case TCP_STATE_LAST_ACK:
2470 case TCP_STATE_FIN_WAIT_1:
2473 if (tc->flags & TCP_CONN_FINPNDG)
2475 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2476 * sending it. Since we already received a fin, do not wait
2478 tc->flags |= TCP_CONN_FINRCVD;
2479 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2480 tcp_cfg.closewait_time);
2484 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2485 tcp_program_ack (tc);
2486 /* Wait for ACK for our FIN but not forever */
2487 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2488 tcp_cfg.closing_time);
2491 case TCP_STATE_FIN_WAIT_2:
2492 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2494 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2495 tcp_connection_timers_reset (tc);
2496 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2497 tcp_cfg.timewait_time);
2498 tcp_program_ack (tc);
2499 session_transport_closed_notify (&tc->connection);
2501 case TCP_STATE_TIME_WAIT:
2502 /* Remain in the TIME-WAIT state. Restart the time-wait
2505 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
2506 tcp_cfg.timewait_time);
2509 error = TCP_ERROR_FIN_RCVD;
2515 tcp_inc_counter (rcv_process, error, 1);
2518 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2520 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2521 tcp_handle_postponed_dequeues (wrk);
2522 tcp_handle_disconnects (wrk);
2523 vlib_buffer_free (vm, from, frame->n_vectors);
2525 return frame->n_vectors;
2528 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2529 vlib_node_runtime_t * node,
2530 vlib_frame_t * from_frame)
2532 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2535 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2536 vlib_node_runtime_t * node,
2537 vlib_frame_t * from_frame)
2539 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2543 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2545 .name = "tcp4-rcv-process",
2546 /* Takes a vector of packets. */
2547 .vector_size = sizeof (u32),
2548 .n_errors = TCP_N_ERROR,
2549 .error_counters = tcp_input_error_counters,
2550 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2553 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2554 foreach_tcp_state_next
2557 .format_trace = format_tcp_rx_trace_short,
2562 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2564 .name = "tcp6-rcv-process",
2565 /* Takes a vector of packets. */
2566 .vector_size = sizeof (u32),
2567 .n_errors = TCP_N_ERROR,
2568 .error_counters = tcp_input_error_counters,
2569 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2572 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2573 foreach_tcp_state_next
2576 .format_trace = format_tcp_rx_trace_short,
2581 tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2582 u32 *to_next, u32 n_bufs)
2584 tcp_connection_t *tc = 0;
2589 for (i = 0; i < n_bufs; i++)
2591 b = vlib_get_buffer (vm, to_next[i]);
2592 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2594 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2595 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2596 t = vlib_add_trace (vm, node, b, sizeof (*t));
2597 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2602 * SYN received in TIME-WAIT state.
2605 * "When a connection is [...] on TIME-WAIT state [...]
2606 * [a TCP] MAY accept a new SYN from the remote TCP to
2607 * reopen the connection directly, if it:
2609 * (1) assigns its initial sequence number for the new
2610 * connection to be larger than the largest sequence
2611 * number it used on the previous connection incarnation,
2614 * (2) returns to TIME-WAIT state if the SYN turns out
2615 * to be an old duplicate".
2617 * The function returns true if the syn can be accepted during
2618 * connection time-wait (port reuse). In this case the function
2619 * also calculates what the iss should be for the new connection.
2622 syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2624 int paws_reject = tcp_segment_check_paws (tc);
2628 /* Check that the SYN arrived out of window. We accept it */
2630 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2631 (tcp_opts_tstamp (&tc->rcv_opts) &&
2632 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2634 /* Set the iss of the new connection to be the largest sequence number
2635 * the old peer would have accepted and add some random number
2637 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2638 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2648 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2649 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2650 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2651 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2657 * LISTEN state processing as per RFC 793 p. 65
2660 tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2661 vlib_frame_t *frame, int is_ip4)
2663 u32 n_left_from, *from, n_syns = 0;
2664 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2665 u32 thread_index = vm->thread_index;
2668 from = vlib_frame_vector_args (frame);
2669 n_left_from = frame->n_vectors;
2671 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2672 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2674 vlib_get_buffers (vm, from, bufs, n_left_from);
2677 while (n_left_from > 0)
2679 tcp_connection_t *lc, *child;
2681 /* Flags initialized with connection state after lookup */
2682 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
2684 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
2686 /* Probably we are in time-wait or closed state */
2689 tcp_connection_t *tc;
2690 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2692 if (tc->state != TCP_STATE_TIME_WAIT)
2694 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2698 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2700 /* This SYN can't be accepted */
2701 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2705 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
2706 /* clean up the old session */
2707 tcp_connection_del (tc);
2708 /* listener was cleaned up */
2711 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
2716 /* Make sure connection wasn't just created */
2718 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
2719 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2721 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
2725 /* Create child session. For syn-flood protection use filter */
2727 /* 1. first check for an RST: handled by input dispatch */
2729 /* 2. second check for an ACK: handled by input dispatch */
2731 /* 3. check for a SYN (did that already) */
2733 /* Create child session and send SYN-ACK */
2734 child = tcp_connection_alloc (thread_index);
2736 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
2738 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
2739 tcp_connection_free (child);
2743 tcp_init_w_buffer (child, b[0], is_ip4);
2745 child->state = TCP_STATE_SYN_RCVD;
2746 child->c_fib_index = lc->c_fib_index;
2747 child->cc_algo = lc->cc_algo;
2749 /* In the regular case, the tw_iss will be zero, but
2750 * in the special case of syn arriving in time_wait state, the value
2751 * will be set according to rfc 1122
2753 child->iss = tw_iss;
2754 tcp_connection_init_vars (child);
2755 child->rto = TCP_RTO_MIN;
2758 * This initializes elog track, must be done before synack.
2759 * We also do it before possible tcp_connection_cleanup() as it
2760 * generates TCP_EVT_DELETE event.
2762 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2764 if (session_stream_accept (&child->connection, lc->c_s_index,
2765 lc->c_thread_index, 0 /* notify */ ))
2767 tcp_connection_cleanup (child);
2768 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
2772 transport_fifos_init_ooo (&child->connection);
2773 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
2775 tcp_send_synack (child);
2783 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
2784 vlib_buffer_free (vm, from, frame->n_vectors);
2786 return frame->n_vectors;
2789 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2790 vlib_frame_t * from_frame)
2792 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2795 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2796 vlib_frame_t * from_frame)
2798 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2802 VLIB_REGISTER_NODE (tcp4_listen_node) =
2804 .name = "tcp4-listen",
2805 /* Takes a vector of packets. */
2806 .vector_size = sizeof (u32),
2807 .n_errors = TCP_N_ERROR,
2808 .error_counters = tcp_input_error_counters,
2809 .n_next_nodes = TCP_LISTEN_N_NEXT,
2812 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2813 foreach_tcp_state_next
2816 .format_trace = format_tcp_rx_trace_short,
2821 VLIB_REGISTER_NODE (tcp6_listen_node) =
2823 .name = "tcp6-listen",
2824 /* Takes a vector of packets. */
2825 .vector_size = sizeof (u32),
2826 .n_errors = TCP_N_ERROR,
2827 .error_counters = tcp_input_error_counters,
2828 .n_next_nodes = TCP_LISTEN_N_NEXT,
2831 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2832 foreach_tcp_state_next
2835 .format_trace = format_tcp_rx_trace_short,
2839 #define foreach_tcp4_input_next \
2840 _ (DROP, "ip4-drop") \
2841 _ (LISTEN, "tcp4-listen") \
2842 _ (RCV_PROCESS, "tcp4-rcv-process") \
2843 _ (SYN_SENT, "tcp4-syn-sent") \
2844 _ (ESTABLISHED, "tcp4-established") \
2845 _ (RESET, "tcp4-reset") \
2846 _ (PUNT, "ip4-punt")
2848 #define foreach_tcp6_input_next \
2849 _ (DROP, "ip6-drop") \
2850 _ (LISTEN, "tcp6-listen") \
2851 _ (RCV_PROCESS, "tcp6-rcv-process") \
2852 _ (SYN_SENT, "tcp6-syn-sent") \
2853 _ (ESTABLISHED, "tcp6-established") \
2854 _ (RESET, "tcp6-reset") \
2855 _ (PUNT, "ip6-punt")
2857 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2860 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2862 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
2864 *next = TCP_INPUT_NEXT_DROP;
2866 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2868 *next = TCP_INPUT_NEXT_PUNT;
2869 *error = TCP_ERROR_PUNT;
2873 *next = TCP_INPUT_NEXT_RESET;
2874 *error = TCP_ERROR_NO_LISTENER;
2879 tcp_input_dispatch_buffer (tcp_main_t *tm, tcp_connection_t *tc,
2880 vlib_buffer_t *b, u16 *next, u16 *err_counters)
2886 tcp = tcp_buffer_hdr (b);
2887 flags = tcp->flags & filter_flags;
2888 *next = tm->dispatch_table[tc->state][flags].next;
2889 error = tm->dispatch_table[tc->state][flags].error;
2892 /* Track connection state when packet was received. It is required
2893 * for @ref tcp46_listen_inline to detect whether we reached
2894 * the node as a result of a SYN packet received while in time-wait
2895 * state. In this case the connection_index in vnet buffer will point
2896 * to the existing tcp connection and not the listener
2898 vnet_buffer (b)->tcp.flags = tc->state;
2900 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
2902 tcp_inc_err_counter (err_counters, error, 1);
2903 if (error == TCP_ERROR_DISPATCH)
2904 clib_warning ("tcp conn %u disp error state %U flags %U",
2905 tc->c_c_index, format_tcp_state, tc->state,
2906 format_tcp_flags, (int) flags);
2911 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2912 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
2914 u32 n_left_from, *from, thread_index = vm->thread_index;
2915 tcp_main_t *tm = vnet_get_tcp_main ();
2916 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2917 u16 nexts[VLIB_FRAME_SIZE], *next;
2918 u16 err_counters[TCP_N_ERROR] = { 0 };
2920 tcp_update_time_now (tcp_get_worker (thread_index));
2922 from = vlib_frame_vector_args (frame);
2923 n_left_from = frame->n_vectors;
2924 vlib_get_buffers (vm, from, bufs, n_left_from);
2929 while (n_left_from >= 4)
2931 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2932 tcp_connection_t *tc0, *tc1;
2935 vlib_prefetch_buffer_header (b[2], STORE);
2936 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2938 vlib_prefetch_buffer_header (b[3], STORE);
2939 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2942 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2944 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2946 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2949 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2951 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2952 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2954 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2955 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2957 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2958 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], err_counters);
2962 if (PREDICT_TRUE (tc0 != 0))
2964 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2965 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2966 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0],
2971 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
2972 tcp_inc_err_counter (err_counters, error0, 1);
2975 if (PREDICT_TRUE (tc1 != 0))
2977 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
2978 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2979 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1],
2984 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
2985 tcp_inc_err_counter (err_counters, error1, 1);
2993 while (n_left_from > 0)
2995 tcp_connection_t *tc0;
2996 u32 error0 = TCP_ERROR_NO_LISTENER;
2998 if (n_left_from > 1)
3000 vlib_prefetch_buffer_header (b[1], STORE);
3001 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3004 next[0] = TCP_INPUT_NEXT_DROP;
3005 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3007 if (PREDICT_TRUE (tc0 != 0))
3009 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3010 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3011 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
3015 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3016 tcp_inc_err_counter (err_counters, error0, 1);
3024 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3025 tcp_input_trace_frame (vm, node, bufs, nexts, frame->n_vectors, is_ip4);
3027 tcp_store_err_counters (input, err_counters);
3028 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3029 return frame->n_vectors;
3032 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3033 vlib_node_runtime_t * node,
3034 vlib_frame_t * from_frame)
3036 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3037 1 /* is_nolookup */ );
3040 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3041 vlib_node_runtime_t * node,
3042 vlib_frame_t * from_frame)
3044 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3045 1 /* is_nolookup */ );
3049 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3051 .name = "tcp4-input-nolookup",
3052 /* Takes a vector of packets. */
3053 .vector_size = sizeof (u32),
3054 .n_errors = TCP_N_ERROR,
3055 .error_counters = tcp_input_error_counters,
3056 .n_next_nodes = TCP_INPUT_N_NEXT,
3059 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3060 foreach_tcp4_input_next
3063 .format_buffer = format_tcp_header,
3064 .format_trace = format_tcp_rx_trace,
3069 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3071 .name = "tcp6-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_tcp6_input_next
3083 .format_buffer = format_tcp_header,
3084 .format_trace = format_tcp_rx_trace,
3088 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3089 vlib_frame_t * from_frame)
3091 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3092 0 /* is_nolookup */ );
3095 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3096 vlib_frame_t * from_frame)
3098 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3099 0 /* is_nolookup */ );
3103 VLIB_REGISTER_NODE (tcp4_input_node) =
3105 .name = "tcp4-input",
3106 /* Takes a vector of packets. */
3107 .vector_size = sizeof (u32),
3108 .n_errors = TCP_N_ERROR,
3109 .error_counters = tcp_input_error_counters,
3110 .n_next_nodes = TCP_INPUT_N_NEXT,
3113 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3114 foreach_tcp4_input_next
3117 .format_buffer = format_tcp_header,
3118 .format_trace = format_tcp_rx_trace,
3123 VLIB_REGISTER_NODE (tcp6_input_node) =
3125 .name = "tcp6-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_tcp6_input_next
3137 .format_buffer = format_tcp_header,
3138 .format_trace = format_tcp_rx_trace,
3142 #ifndef CLIB_MARCH_VARIANT
3144 tcp_check_gso (tcp_connection_t *tc)
3146 tcp_check_tx_offload (tc, tc->c_is_ip4);
3150 tcp_dispatch_table_init (tcp_main_t * tm)
3153 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3154 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3156 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3157 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3160 #define _(t,f,n,e) \
3162 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3163 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3166 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3167 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3168 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3169 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3170 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3171 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3172 TCP_ERROR_ACK_INVALID);
3173 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3174 TCP_ERROR_SEGMENT_INVALID);
3175 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3176 TCP_ERROR_SEGMENT_INVALID);
3177 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3178 TCP_ERROR_INVALID_CONNECTION);
3179 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3180 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3181 TCP_ERROR_SEGMENT_INVALID);
3182 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3183 TCP_ERROR_SEGMENT_INVALID);
3184 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3185 TCP_ERROR_SEGMENT_INVALID);
3186 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3187 TCP_ERROR_SEGMENT_INVALID);
3188 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3189 TCP_ERROR_SEGMENT_INVALID);
3190 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3191 TCP_ERROR_SEGMENT_INVALID);
3192 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3193 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3194 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3195 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3196 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3197 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3199 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3200 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3202 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3204 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3205 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3206 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3207 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3209 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3211 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3212 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3213 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3215 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3216 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3217 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3218 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3220 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3221 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3222 /* SYN-ACK for a SYN */
3223 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3225 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3226 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3227 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3229 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3230 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3232 /* ACK for for established connection -> tcp-established. */
3233 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3234 /* FIN for for established connection -> tcp-established. */
3235 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3236 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3238 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3240 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3241 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3242 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3244 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3245 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3246 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3247 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3248 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3249 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3250 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3251 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3253 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3254 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3256 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3258 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3259 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3260 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3261 /* ACK or FIN-ACK to our FIN */
3262 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3263 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3265 /* FIN in reply to our FIN from the other side */
3266 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3267 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3268 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3270 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3271 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3272 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3273 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3274 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3275 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3276 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3278 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3279 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3280 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3281 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3283 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3285 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3286 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3287 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3288 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3290 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3291 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3292 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3293 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3295 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3297 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3298 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3299 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3300 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3302 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3303 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3305 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3307 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3308 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3309 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3311 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3312 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3313 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3314 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3315 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3316 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3317 /* FIN confirming that the peer (app) has closed */
3318 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3319 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3320 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3322 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3323 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3325 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3326 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3327 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3329 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3330 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3332 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3333 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3334 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3335 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3336 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3338 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3340 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3341 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3342 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3344 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3345 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3346 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3347 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3348 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3349 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3350 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3351 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3353 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3354 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3356 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3358 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3359 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3360 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3361 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3362 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3364 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3365 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3367 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3368 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3369 * incoming segment not containing a RST causes a RST to be sent in
3371 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3372 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3373 TCP_ERROR_CONNECTION_CLOSED);
3374 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
3375 _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3376 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3377 TCP_ERROR_CONNECTION_CLOSED);
3381 static clib_error_t *
3382 tcp_input_init (vlib_main_t * vm)
3384 clib_error_t *error = 0;
3385 tcp_main_t *tm = vnet_get_tcp_main ();
3387 if ((error = vlib_call_init_function (vm, tcp_init)))
3390 /* Initialize dispatch table. */
3391 tcp_dispatch_table_init (tm);
3396 VLIB_INIT_FUNCTION (tcp_input_init);
3398 #endif /* CLIB_MARCH_VARIANT */
3401 * fd.io coding-style-patch-verification: ON
3404 * eval: (c-set-style "gnu")