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_packet.h>
20 #include <vnet/tcp/tcp.h>
21 #include <vnet/session/session.h>
24 static char *tcp_error_strings[] = {
25 #define tcp_error(n,s) s,
26 #include <vnet/tcp/tcp_error.def>
30 /* All TCP nodes have the same outgoing arcs */
31 #define foreach_tcp_state_next \
32 _ (DROP4, "ip4-drop") \
33 _ (DROP6, "ip6-drop") \
34 _ (TCP4_OUTPUT, "tcp4-output") \
35 _ (TCP6_OUTPUT, "tcp6-output")
37 typedef enum _tcp_established_next
39 #define _(s,n) TCP_ESTABLISHED_NEXT_##s,
40 foreach_tcp_state_next
42 TCP_ESTABLISHED_N_NEXT,
43 } tcp_established_next_t;
45 typedef enum _tcp_rcv_process_next
47 #define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
48 foreach_tcp_state_next
50 TCP_RCV_PROCESS_N_NEXT,
51 } tcp_rcv_process_next_t;
53 typedef enum _tcp_syn_sent_next
55 #define _(s,n) TCP_SYN_SENT_NEXT_##s,
56 foreach_tcp_state_next
59 } tcp_syn_sent_next_t;
61 typedef enum _tcp_listen_next
63 #define _(s,n) TCP_LISTEN_NEXT_##s,
64 foreach_tcp_state_next
69 /* Generic, state independent indices */
70 typedef enum _tcp_state_next
72 #define _(s,n) TCP_NEXT_##s,
73 foreach_tcp_state_next
78 #define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
79 : TCP_NEXT_TCP6_OUTPUT)
81 #define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
85 * Validate segment sequence number. As per RFC793:
87 * Segment Receive Test
89 * ------- ------- -------------------------------------------
90 * 0 0 SEG.SEQ = RCV.NXT
91 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
93 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
94 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
96 * This ultimately consists in checking if segment falls within the window.
97 * The one important difference compared to RFC793 is that we use rcv_las,
98 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
99 * peer's reference when computing our receive window.
102 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
103 * however, is too strict when we have retransmits. Instead we just check that
104 * the seq is not beyond the right edge and that the end of the segment is not
105 * less than the left edge.
107 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
108 * use rcv_nxt in the right edge window test instead of rcv_las.
112 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
114 return (seq_geq (end_seq, tc->rcv_las)
115 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
119 * Parse TCP header options.
121 * @param th TCP header
122 * @param to TCP options data structure to be populated
123 * @param is_syn set if packet is syn
124 * @return -1 if parsing failed
127 tcp_options_parse (tcp_header_t * th, tcp_options_t * to, u8 is_syn)
130 u8 opt_len, opts_len, kind;
134 opts_len = (tcp_doff (th) << 2) - sizeof (tcp_header_t);
135 data = (const u8 *) (th + 1);
137 /* Zero out all flags but those set in SYN */
138 to->flags &= (TCP_OPTS_FLAG_SACK_PERMITTED | TCP_OPTS_FLAG_WSCALE
139 | TCP_OPTS_FLAG_TSTAMP | TCP_OPTS_FLAG_MSS);
141 for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
145 /* Get options length */
146 if (kind == TCP_OPTION_EOL)
148 else if (kind == TCP_OPTION_NOOP)
160 /* weird option length */
161 if (opt_len < 2 || opt_len > opts_len)
171 if ((opt_len == TCP_OPTION_LEN_MSS) && tcp_syn (th))
173 to->flags |= TCP_OPTS_FLAG_MSS;
174 to->mss = clib_net_to_host_u16 (*(u16 *) (data + 2));
177 case TCP_OPTION_WINDOW_SCALE:
180 if ((opt_len == TCP_OPTION_LEN_WINDOW_SCALE) && tcp_syn (th))
182 to->flags |= TCP_OPTS_FLAG_WSCALE;
183 to->wscale = data[2];
184 if (to->wscale > TCP_MAX_WND_SCALE)
185 to->wscale = TCP_MAX_WND_SCALE;
188 case TCP_OPTION_TIMESTAMP:
190 to->flags |= TCP_OPTS_FLAG_TSTAMP;
191 if ((to->flags & TCP_OPTS_FLAG_TSTAMP)
192 && opt_len == TCP_OPTION_LEN_TIMESTAMP)
194 to->tsval = clib_net_to_host_u32 (*(u32 *) (data + 2));
195 to->tsecr = clib_net_to_host_u32 (*(u32 *) (data + 6));
198 case TCP_OPTION_SACK_PERMITTED:
201 if (opt_len == TCP_OPTION_LEN_SACK_PERMITTED && tcp_syn (th))
202 to->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
204 case TCP_OPTION_SACK_BLOCK:
205 /* If SACK permitted was not advertised or a SYN, break */
206 if ((to->flags & TCP_OPTS_FLAG_SACK_PERMITTED) == 0 || tcp_syn (th))
209 /* If too short or not correctly formatted, break */
210 if (opt_len < 10 || ((opt_len - 2) % TCP_OPTION_LEN_SACK_BLOCK))
213 to->flags |= TCP_OPTS_FLAG_SACK;
214 to->n_sack_blocks = (opt_len - 2) / TCP_OPTION_LEN_SACK_BLOCK;
215 vec_reset_length (to->sacks);
216 for (j = 0; j < to->n_sack_blocks; j++)
218 b.start = clib_net_to_host_u32 (*(u32 *) (data + 2 + 8 * j));
219 b.end = clib_net_to_host_u32 (*(u32 *) (data + 6 + 8 * j));
220 vec_add1 (to->sacks, b);
224 /* Nothing to see here */
232 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
233 * timestamp to echo and it's less than tsval_recent, drop segment
234 * but still send an ACK in order to retain TCP's mechanism for detecting
235 * and recovering from half-open connections
237 * Or at least that's what the theory says. It seems that this might not work
238 * very well with packet reordering and fast retransmit. XXX
241 tcp_segment_check_paws (tcp_connection_t * tc)
243 return tcp_opts_tstamp (&tc->rcv_opts)
244 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
248 * Update tsval recent
251 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
254 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
255 * of an incoming segment:
256 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
257 * then the TSval from the segment is copied to TS.Recent;
258 * otherwise, the TSval is ignored.
260 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
261 && seq_leq (tc->rcv_las, seq_end))
263 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
264 tc->tsval_recent = tc->rcv_opts.tsval;
265 tc->tsval_recent_age = tcp_time_now_w_thread (tc->c_thread_index);
270 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
272 * It first verifies if segment has a wrapped sequence number (PAWS) and then
273 * does the processing associated to the first four steps (ignoring security
274 * and precedence): sequence number, rst bit and syn bit checks.
276 * @return 0 if segments passes validation.
279 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
280 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
282 /* We could get a burst of RSTs interleaved with acks */
283 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
285 tcp_send_reset (tc0);
286 *error0 = TCP_ERROR_CONNECTION_CLOSED;
290 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
292 *error0 = TCP_ERROR_SEGMENT_INVALID;
296 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
298 *error0 = TCP_ERROR_OPTIONS;
302 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
304 *error0 = TCP_ERROR_PAWS;
305 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
306 vnet_buffer (b0)->tcp.seq_end);
308 /* If it just so happens that a segment updates tsval_recent for a
309 * segment over 24 days old, invalidate tsval_recent. */
310 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
311 tcp_time_now_w_thread (tc0->c_thread_index)))
313 tc0->tsval_recent = tc0->rcv_opts.tsval;
314 clib_warning ("paws failed: 24-day old segment");
316 /* Drop after ack if not rst. Resets can fail paws check as per
317 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
318 * be subjected to the PAWS check by verifying an acceptable value in
320 else if (!tcp_rst (th0))
322 tcp_program_ack (tc0);
323 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
328 /* 1st: check sequence number */
329 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
330 vnet_buffer (b0)->tcp.seq_end))
332 /* SYN/SYN-ACK retransmit */
334 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
336 tcp_options_parse (th0, &tc0->rcv_opts, 1);
337 if (tc0->state == TCP_STATE_SYN_RCVD)
339 tcp_send_synack (tc0);
340 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
341 *error0 = TCP_ERROR_SYNS_RCVD;
345 tcp_program_ack (tc0);
346 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
347 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
352 /* If our window is 0 and the packet is in sequence, let it pass
353 * through for ack processing. It should be dropped later. */
354 if (tc0->rcv_wnd < tc0->snd_mss
355 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
358 /* If we entered recovery and peer did so as well, there's a chance that
359 * dup acks won't be acceptable on either end because seq_end may be less
360 * than rcv_las. This can happen if acks are lost in both directions. */
361 if (tcp_in_recovery (tc0)
362 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
363 tc0->rcv_las - tc0->rcv_wnd)
364 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
365 tc0->rcv_nxt + tc0->rcv_wnd))
368 *error0 = TCP_ERROR_RCV_WND;
370 /* If we advertised a zero rcv_wnd and the segment is in the past or the
371 * next one that we expect, it is probably a window probe */
372 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
373 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
374 tc0->rcv_las + tc0->rcv_opts.mss))
375 *error0 = TCP_ERROR_ZERO_RWND;
377 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
380 /* If not RST, send dup ack */
383 tcp_program_dupack (tc0);
384 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
392 /* 2nd: check the RST bit */
393 if (PREDICT_FALSE (tcp_rst (th0)))
395 tcp_connection_reset (tc0);
396 *error0 = TCP_ERROR_RST_RCVD;
400 /* 3rd: check security and precedence (skip) */
402 /* 4th: check the SYN bit (in window) */
403 if (PREDICT_FALSE (tcp_syn (th0)))
405 /* As per RFC5961 send challenge ack instead of reset */
406 tcp_program_ack (tc0);
407 *error0 = TCP_ERROR_SPURIOUS_SYN;
411 /* If segment in window, save timestamp */
412 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
413 vnet_buffer (b0)->tcp.seq_end);
421 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
423 /* SND.UNA =< SEG.ACK =< SND.NXT */
424 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
425 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
427 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
428 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
430 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
433 *error = TCP_ERROR_ACK_INVALID;
438 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
439 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
440 *error = TCP_ERROR_ACK_OK;
445 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
447 * Note that although the original article, srtt and rttvar are scaled
448 * to minimize round-off errors, here we don't. Instead, we rely on
449 * better precision time measurements.
451 * TODO support us rtt resolution
454 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
460 err = mrtt - tc->srtt;
462 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
463 * The increase should be bound */
464 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
465 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
466 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
470 /* First measurement. */
472 tc->rttvar = mrtt >> 1;
476 #ifndef CLIB_MARCH_VARIANT
478 tcp_update_rto (tcp_connection_t * tc)
480 tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
481 tc->rto = clib_max (tc->rto, TCP_RTO_MIN);
483 #endif /* CLIB_MARCH_VARIANT */
486 * Update RTT estimate and RTO timer
488 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
489 * timing. Middle boxes are known to fiddle with TCP options so we
490 * should give higher priority to ACK timing.
492 * This should be called only if previously sent bytes have been acked.
494 * return 1 if valid rtt 0 otherwise
497 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
501 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
502 * RTT because they're ambiguous. */
503 if (tcp_in_cong_recovery (tc))
505 /* Accept rtt estimates for samples that have not been retransmitted */
506 if ((tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
507 && !(rs->flags & TCP_BTS_IS_RXT))
509 mrtt = rs->rtt_time * THZ;
515 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
517 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
518 tc->mrtt_us = tc->mrtt_us + (sample - tc->mrtt_us) * 0.125;
519 mrtt = clib_max ((u32) (sample * THZ), 1);
520 /* Allow measuring of a new RTT */
523 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
524 * snd_una, i.e., the left side of the send window:
525 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
526 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
528 u32 now = tcp_tstamp (tc);
529 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
534 /* Ignore dubious measurements */
535 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
538 tcp_estimate_rtt (tc, mrtt);
542 /* If we got here something must've been ACKed so make sure boff is 0,
543 * even if mrtt is not valid since we update the rto lower */
551 tcp_estimate_initial_rtt (tcp_connection_t * tc)
553 u8 thread_index = vlib_num_workers ()? 1 : 0;
558 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
559 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
560 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
565 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
566 mrtt = clib_max (mrtt, 1);
567 /* Due to retransmits we don't know the initial mrtt */
568 if (tc->rto_boff && mrtt > 1 * THZ)
570 tc->mrtt_us = (f64) mrtt *TCP_TICK;
573 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
574 tcp_estimate_rtt (tc, mrtt);
579 tcp_recovery_no_snd_space (tcp_connection_t * tc)
581 return (tcp_in_fastrecovery (tc)
582 && tcp_fastrecovery_prr_snd_space (tc) < tc->snd_mss)
583 || (tcp_in_recovery (tc)
584 && tcp_available_output_snd_space (tc) < tc->snd_mss);
588 * Dequeue bytes for connections that have received acks in last burst
591 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
593 u32 thread_index = wrk->vm->thread_index;
594 u32 *pending_deq_acked;
595 tcp_connection_t *tc;
598 if (!vec_len (wrk->pending_deq_acked))
601 pending_deq_acked = wrk->pending_deq_acked;
602 for (i = 0; i < vec_len (pending_deq_acked); i++)
604 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
605 tc->flags &= ~TCP_CONN_DEQ_PENDING;
609 /* Dequeue the newly ACKed bytes */
610 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
612 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
614 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
616 if (seq_leq (tc->psh_seq, tc->snd_una))
617 tc->flags &= ~TCP_CONN_PSH_PENDING;
620 /* If everything has been acked, stop retransmit timer
621 * otherwise update. */
622 tcp_retransmit_timer_update (tc);
624 /* Update pacer based on our new cwnd estimate */
625 tcp_connection_tx_pacer_update (tc);
628 /* Reset the pacer if we've been idle, i.e., no data sent or if
629 * we're in recovery and snd space constrained */
630 if (tc->data_segs_out == tc->prev_dsegs_out
631 || tcp_recovery_no_snd_space (tc))
632 transport_connection_tx_pacer_reset_bucket (&tc->connection);
633 tc->prev_dsegs_out = tc->data_segs_out;
635 _vec_len (wrk->pending_deq_acked) = 0;
639 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
641 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
643 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
644 tc->flags |= TCP_CONN_DEQ_PENDING;
646 tc->burst_acked += tc->bytes_acked;
649 #ifndef CLIB_MARCH_VARIANT
651 scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
653 ASSERT (!pool_is_free_index (sb->holes, hole - sb->holes));
654 return hole - sb->holes;
658 scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
660 return hole->end - hole->start;
663 sack_scoreboard_hole_t *
664 scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
666 if (index != TCP_INVALID_SACK_HOLE_INDEX)
667 return pool_elt_at_index (sb->holes, index);
671 sack_scoreboard_hole_t *
672 scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
674 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
675 return pool_elt_at_index (sb->holes, hole->next);
679 sack_scoreboard_hole_t *
680 scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
682 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
683 return pool_elt_at_index (sb->holes, hole->prev);
687 sack_scoreboard_hole_t *
688 scoreboard_first_hole (sack_scoreboard_t * sb)
690 if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
691 return pool_elt_at_index (sb->holes, sb->head);
695 sack_scoreboard_hole_t *
696 scoreboard_last_hole (sack_scoreboard_t * sb)
698 if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
699 return pool_elt_at_index (sb->holes, sb->tail);
704 scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
706 sack_scoreboard_hole_t *next, *prev;
708 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
710 next = pool_elt_at_index (sb->holes, hole->next);
711 next->prev = hole->prev;
715 sb->tail = hole->prev;
718 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
720 prev = pool_elt_at_index (sb->holes, hole->prev);
721 prev->next = hole->next;
725 sb->head = hole->next;
728 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
729 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
731 /* Poison the entry */
733 clib_memset (hole, 0xfe, sizeof (*hole));
735 pool_put (sb->holes, hole);
738 static sack_scoreboard_hole_t *
739 scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
742 sack_scoreboard_hole_t *hole, *next, *prev;
745 pool_get (sb->holes, hole);
746 clib_memset (hole, 0, sizeof (*hole));
750 hole_index = scoreboard_hole_index (sb, hole);
752 prev = scoreboard_get_hole (sb, prev_index);
755 hole->prev = prev_index;
756 hole->next = prev->next;
758 if ((next = scoreboard_next_hole (sb, hole)))
759 next->prev = hole_index;
761 sb->tail = hole_index;
763 prev->next = hole_index;
767 sb->head = hole_index;
768 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
769 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
776 scoreboard_update_sacked_rxt (sack_scoreboard_t * sb, u32 start, u32 end,
779 if (!has_rxt || seq_geq (start, sb->high_rxt))
783 seq_lt (end, sb->high_rxt) ? (end - start) : (sb->high_rxt - start);
787 scoreboard_update_bytes (sack_scoreboard_t * sb, u32 ack, u32 snd_mss)
789 sack_scoreboard_hole_t *left, *right;
790 u32 sacked = 0, blks = 0, old_sacked;
792 old_sacked = sb->sacked_bytes;
794 sb->last_lost_bytes = 0;
796 sb->sacked_bytes = 0;
798 right = scoreboard_last_hole (sb);
801 sb->sacked_bytes = sb->high_sacked - ack;
805 if (seq_gt (sb->high_sacked, right->end))
807 sacked = sb->high_sacked - right->end;
811 while (sacked < (TCP_DUPACK_THRESHOLD - 1) * snd_mss
812 && blks < TCP_DUPACK_THRESHOLD)
815 sb->lost_bytes += scoreboard_hole_bytes (right);
817 left = scoreboard_prev_hole (sb, right);
820 ASSERT (right->start == ack || sb->is_reneging);
821 sacked += right->start - ack;
826 sacked += right->start - left->end;
831 /* right is first lost */
834 sb->lost_bytes += scoreboard_hole_bytes (right);
835 sb->last_lost_bytes += right->is_lost ? 0 : (right->end - right->start);
837 left = scoreboard_prev_hole (sb, right);
840 ASSERT (right->start == ack || sb->is_reneging);
841 sacked += right->start - ack;
844 sacked += right->start - left->end;
848 sb->sacked_bytes = sacked;
849 sb->last_sacked_bytes = sacked - (old_sacked - sb->last_bytes_delivered);
853 * Figure out the next hole to retransmit
855 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
857 sack_scoreboard_hole_t *
858 scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
859 sack_scoreboard_hole_t * start,
860 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
862 sack_scoreboard_hole_t *hole = 0;
864 hole = start ? start : scoreboard_first_hole (sb);
865 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
866 hole = scoreboard_next_hole (sb, hole);
868 /* Nothing, return */
871 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
875 /* Rule (1): if higher than rxt, less than high_sacked and lost */
876 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
878 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
882 /* Rule (2): available unsent data */
885 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
888 /* Rule (3): if hole not lost */
889 else if (seq_lt (hole->start, sb->high_sacked))
891 /* And we didn't already retransmit it */
892 if (seq_leq (hole->end, sb->high_rxt))
894 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
898 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
900 /* Rule (4): if hole beyond high_sacked */
903 ASSERT (seq_geq (hole->start, sb->high_sacked));
906 /* HighRxt MUST NOT be updated */
911 if (hole && seq_lt (sb->high_rxt, hole->start))
912 sb->high_rxt = hole->start;
918 scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una)
920 sack_scoreboard_hole_t *hole;
921 hole = scoreboard_first_hole (sb);
924 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
925 sb->cur_rxt_hole = sb->head;
927 sb->high_rxt = snd_una;
928 sb->rescue_rxt = snd_una - 1;
932 scoreboard_init (sack_scoreboard_t * sb)
934 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
935 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
936 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
940 scoreboard_clear (sack_scoreboard_t * sb)
942 sack_scoreboard_hole_t *hole;
943 while ((hole = scoreboard_first_hole (sb)))
945 scoreboard_remove_hole (sb, hole);
947 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
948 ASSERT (pool_elts (sb->holes) == 0);
949 sb->sacked_bytes = 0;
950 sb->last_sacked_bytes = 0;
951 sb->last_bytes_delivered = 0;
953 sb->last_lost_bytes = 0;
954 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
959 scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end)
961 sack_scoreboard_hole_t *last_hole;
963 clib_warning ("sack reneging");
965 scoreboard_clear (sb);
966 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
968 last_hole->is_lost = 1;
969 sb->tail = scoreboard_hole_index (sb, last_hole);
970 sb->high_sacked = start;
971 scoreboard_init_rxt (sb, start);
974 #endif /* CLIB_MARCH_VARIANT */
977 * Test that scoreboard is sane after recovery
979 * Returns 1 if scoreboard is empty or if first hole beyond
983 tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
985 sack_scoreboard_hole_t *hole;
986 hole = scoreboard_first_hole (&tc->sack_sb);
987 return (!hole || (seq_geq (hole->start, tc->snd_una)
988 && seq_lt (hole->end, tc->snd_nxt)));
991 #ifndef CLIB_MARCH_VARIANT
994 tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
996 sack_scoreboard_hole_t *hole, *next_hole;
997 sack_scoreboard_t *sb = &tc->sack_sb;
998 sack_block_t *blk, *rcv_sacks;
999 u32 blk_index = 0, i, j;
1002 sb->last_sacked_bytes = 0;
1003 sb->last_bytes_delivered = 0;
1006 if (!tcp_opts_sack (&tc->rcv_opts)
1007 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1010 has_rxt = tcp_in_cong_recovery (tc);
1012 /* Remove invalid blocks */
1013 blk = tc->rcv_opts.sacks;
1014 while (blk < vec_end (tc->rcv_opts.sacks))
1016 if (seq_lt (blk->start, blk->end)
1017 && seq_gt (blk->start, tc->snd_una)
1018 && seq_gt (blk->start, ack)
1019 && seq_lt (blk->start, tc->snd_nxt)
1020 && seq_leq (blk->end, tc->snd_nxt))
1025 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
1028 /* Add block for cumulative ack */
1029 if (seq_gt (ack, tc->snd_una))
1031 vec_add2 (tc->rcv_opts.sacks, blk, 1);
1032 blk->start = tc->snd_una;
1036 if (vec_len (tc->rcv_opts.sacks) == 0)
1039 tcp_scoreboard_trace_add (tc, ack);
1041 /* Make sure blocks are ordered */
1042 rcv_sacks = tc->rcv_opts.sacks;
1043 for (i = 0; i < vec_len (rcv_sacks); i++)
1044 for (j = i + 1; j < vec_len (rcv_sacks); j++)
1045 if (seq_lt (rcv_sacks[j].start, rcv_sacks[i].start))
1047 sack_block_t tmp = rcv_sacks[i];
1048 rcv_sacks[i] = rcv_sacks[j];
1052 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1054 /* Handle reneging as a special case */
1055 if (PREDICT_FALSE (sb->is_reneging))
1057 /* No holes, only sacked bytes */
1058 if (seq_leq (tc->snd_nxt, sb->high_sacked))
1060 /* No progress made so return */
1061 if (seq_leq (ack, tc->snd_una))
1064 /* Update sacked bytes delivered and return */
1065 sb->last_bytes_delivered = ack - tc->snd_una;
1066 sb->sacked_bytes -= sb->last_bytes_delivered;
1067 sb->is_reneging = seq_lt (ack, sb->high_sacked);
1071 /* New hole above high sacked. Add it and process normally */
1072 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1073 sb->high_sacked, tc->snd_nxt);
1074 sb->tail = scoreboard_hole_index (sb, hole);
1076 /* Not reneging and no holes. Insert the first that covers all
1077 * outstanding bytes */
1080 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1081 tc->snd_una, tc->snd_nxt);
1082 sb->tail = scoreboard_hole_index (sb, hole);
1084 sb->high_sacked = rcv_sacks[vec_len (rcv_sacks) - 1].end;
1088 /* If we have holes but snd_nxt is beyond the last hole, update
1089 * last hole end or add new hole after high sacked */
1090 hole = scoreboard_last_hole (sb);
1091 if (seq_gt (tc->snd_nxt, hole->end))
1093 if (seq_geq (hole->start, sb->high_sacked))
1095 hole->end = tc->snd_nxt;
1097 /* New hole after high sacked block */
1098 else if (seq_lt (sb->high_sacked, tc->snd_nxt))
1100 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
1105 /* Keep track of max byte sacked for when the last hole
1107 sb->high_sacked = seq_max (rcv_sacks[vec_len (rcv_sacks) - 1].end,
1111 /* Walk the holes with the SACK blocks */
1112 hole = pool_elt_at_index (sb->holes, sb->head);
1114 if (PREDICT_FALSE (sb->is_reneging))
1115 sb->last_bytes_delivered += hole->start - tc->snd_una;
1117 while (hole && blk_index < vec_len (rcv_sacks))
1119 blk = &rcv_sacks[blk_index];
1120 if (seq_leq (blk->start, hole->start))
1122 /* Block covers hole. Remove hole */
1123 if (seq_geq (blk->end, hole->end))
1125 next_hole = scoreboard_next_hole (sb, hole);
1127 /* If covered by ack, compute delivered bytes */
1128 if (blk->end == ack)
1130 u32 sacked = next_hole ? next_hole->start : sb->high_sacked;
1131 if (PREDICT_FALSE (seq_lt (ack, sacked)))
1133 sb->last_bytes_delivered += ack - hole->end;
1134 sb->is_reneging = 1;
1138 sb->last_bytes_delivered += sacked - hole->end;
1139 sb->is_reneging = 0;
1142 scoreboard_update_sacked_rxt (sb, hole->start, hole->end,
1144 scoreboard_remove_hole (sb, hole);
1147 /* Partial 'head' overlap */
1150 if (seq_gt (blk->end, hole->start))
1152 scoreboard_update_sacked_rxt (sb, hole->start, blk->end,
1154 hole->start = blk->end;
1161 /* Hole must be split */
1162 if (seq_lt (blk->end, hole->end))
1164 u32 hole_index = scoreboard_hole_index (sb, hole);
1165 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1167 /* Pool might've moved */
1168 hole = scoreboard_get_hole (sb, hole_index);
1169 hole->end = blk->start;
1171 scoreboard_update_sacked_rxt (sb, blk->start, blk->end,
1175 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
1177 else if (seq_lt (blk->start, hole->end))
1179 scoreboard_update_sacked_rxt (sb, blk->start, hole->end,
1181 hole->end = blk->start;
1183 hole = scoreboard_next_hole (sb, hole);
1187 scoreboard_update_bytes (sb, ack, tc->snd_mss);
1189 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
1190 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
1191 || sb->sacked_bytes <= tc->snd_nxt - seq_max (tc->snd_una, ack));
1192 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_nxt
1193 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
1194 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1195 || sb->is_reneging || sb->holes[sb->head].start == ack);
1196 ASSERT (sb->last_lost_bytes <= sb->lost_bytes);
1197 ASSERT ((ack - tc->snd_una) + sb->last_sacked_bytes
1198 - sb->last_bytes_delivered >= sb->rxt_sacked);
1199 ASSERT ((ack - tc->snd_una) >= tc->sack_sb.last_bytes_delivered
1200 || (tc->flags & TCP_CONN_FINSNT));
1202 TCP_EVT (TCP_EVT_CC_SCOREBOARD, tc);
1204 #endif /* CLIB_MARCH_VARIANT */
1207 * Try to update snd_wnd based on feedback received from peer.
1209 * If successful, and new window is 'effectively' 0, activate persist
1213 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1215 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1216 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
1217 if (seq_lt (tc->snd_wl1, seq)
1218 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
1220 tc->snd_wnd = snd_wnd;
1223 TCP_EVT (TCP_EVT_SND_WND, tc);
1225 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
1227 /* Set persist timer if not set and we just got 0 wnd */
1228 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1229 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
1230 tcp_persist_timer_set (tc);
1234 tcp_persist_timer_reset (tc);
1235 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
1238 tcp_update_rto (tc);
1245 * Init loss recovery/fast recovery.
1247 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1248 * updated in @ref tcp_cc_handle_event after fast retransmit
1251 tcp_cc_init_congestion (tcp_connection_t * tc)
1253 tcp_fastrecovery_on (tc);
1254 tc->snd_congestion = tc->snd_nxt;
1255 tc->cwnd_acc_bytes = 0;
1256 tc->snd_rxt_bytes = 0;
1257 tc->rxt_delivered = 0;
1258 tc->prr_delivered = 0;
1259 tc->prr_start = tc->snd_una;
1260 tc->prev_ssthresh = tc->ssthresh;
1261 tc->prev_cwnd = tc->cwnd;
1263 tc->snd_rxt_ts = tcp_tstamp (tc);
1264 tcp_cc_congestion (tc);
1266 /* Post retransmit update cwnd to ssthresh and account for the
1267 * three segments that have left the network and should've been
1268 * buffered at the receiver XXX */
1269 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
1270 tc->cwnd += 3 * tc->snd_mss;
1272 tc->fr_occurences += 1;
1273 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
1277 tcp_cc_congestion_undo (tcp_connection_t * tc)
1279 tc->cwnd = tc->prev_cwnd;
1280 tc->ssthresh = tc->prev_ssthresh;
1281 tcp_cc_undo_recovery (tc);
1282 ASSERT (tc->rto_boff == 0);
1283 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
1287 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
1289 return (tcp_in_recovery (tc) && tc->rto_boff == 1
1291 && tcp_opts_tstamp (&tc->rcv_opts)
1292 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1296 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1298 return (tcp_cc_is_spurious_timeout_rxt (tc));
1302 tcp_should_fastrecover_sack (tcp_connection_t * tc)
1304 return (tc->sack_sb.lost_bytes
1305 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
1306 < tc->sack_sb.sacked_bytes));
1310 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
1314 /* If of of the two conditions lower hold, reset dupacks because
1315 * we're probably after timeout (RFC6582 heuristics).
1316 * If Cumulative ack does not cover more than congestion threshold,
1318 * 1) The following doesn't hold: The congestion window is greater
1319 * than SMSS bytes and the difference between highest_ack
1320 * and prev_highest_ack is at most 4*SMSS bytes
1321 * 2) Echoed timestamp in the last non-dup ack does not equal the
1324 if (seq_leq (tc->snd_una, tc->snd_congestion)
1325 && ((!(tc->cwnd > tc->snd_mss
1326 && tc->bytes_acked <= 4 * tc->snd_mss))
1327 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1329 tc->rcv_dupacks = 0;
1333 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1334 || tcp_should_fastrecover_sack (tc));
1338 tcp_cc_recover (tcp_connection_t * tc)
1340 sack_scoreboard_hole_t *hole;
1343 ASSERT (tcp_in_cong_recovery (tc));
1345 if (tcp_cc_is_spurious_retransmit (tc))
1347 tcp_cc_congestion_undo (tc);
1351 tc->rcv_dupacks = 0;
1352 tc->prr_delivered = 0;
1353 tc->rxt_delivered = 0;
1354 tc->snd_rxt_bytes = 0;
1357 tc->flags &= ~TCP_CONN_RXT_PENDING;
1359 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1361 /* Previous recovery left us congested. Continue sending as part
1362 * of the current recovery event with an updated snd_congestion */
1363 if (tc->sack_sb.sacked_bytes)
1365 tc->snd_congestion = tc->snd_nxt;
1366 tc->snd_rxt_ts = tcp_tstamp (tc);
1367 tc->prr_start = tc->snd_una;
1368 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1369 tcp_program_retransmit (tc);
1373 hole = scoreboard_first_hole (&tc->sack_sb);
1374 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
1375 scoreboard_clear (&tc->sack_sb);
1377 if (!tcp_in_recovery (tc) && !is_spurious)
1378 tcp_cc_recovered (tc);
1380 tcp_fastrecovery_off (tc);
1381 tcp_fastrecovery_first_off (tc);
1382 tcp_recovery_off (tc);
1383 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1385 ASSERT (tc->rto_boff == 0);
1386 ASSERT (!tcp_in_cong_recovery (tc));
1387 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
1392 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1394 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
1396 /* Congestion avoidance */
1397 tcp_cc_rcv_ack (tc, rs);
1399 /* If a cumulative ack, make sure dupacks is 0 */
1400 tc->rcv_dupacks = 0;
1402 /* When dupacks hits the threshold we only enter fast retransmit if
1403 * cumulative ack covers more than snd_congestion. Should snd_una
1404 * wrap this test may fail under otherwise valid circumstances.
1405 * Therefore, proactively update snd_congestion when wrap detected. */
1407 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1408 && seq_gt (tc->snd_congestion, tc->snd_una)))
1409 tc->snd_congestion = tc->snd_una - 1;
1413 * One function to rule them all ... and in the darkness bind them
1416 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
1419 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
1422 * If not in recovery, figure out if we should enter
1424 if (!tcp_in_cong_recovery (tc))
1429 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1430 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1432 if (tcp_should_fastrecover (tc, has_sack))
1434 tcp_cc_init_congestion (tc);
1437 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1439 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1440 tcp_program_retransmit (tc);
1447 * Already in recovery. See if we can exit and stop retransmitting
1450 if (seq_geq (tc->snd_una, tc->snd_congestion))
1452 /* If spurious return, we've already updated everything */
1453 if (tcp_cc_recover (tc))
1455 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1459 /* Treat as congestion avoidance ack */
1460 tcp_cc_rcv_ack (tc, rs);
1465 * Process (re)transmit feedback. Output path uses this to decide how much
1466 * more data to release into the network
1470 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
1471 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
1472 - tc->sack_sb.last_bytes_delivered;
1474 tcp_program_retransmit (tc);
1480 tc->rcv_dupacks += 1;
1481 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1483 tc->rxt_delivered = clib_max (tc->rxt_delivered + tc->bytes_acked,
1486 tc->prr_delivered += clib_min (tc->snd_mss,
1487 tc->snd_nxt - tc->snd_una);
1489 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
1493 /* If partial ack, assume that the first un-acked segment was lost */
1494 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1495 tcp_fastrecovery_first_on (tc);
1497 tcp_program_retransmit (tc);
1501 * Notify cc of the event
1504 if (!tc->bytes_acked)
1506 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1510 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1511 * reset dupacks to 0. Also needed if in congestion recovery */
1512 tc->rcv_dupacks = 0;
1514 if (tcp_in_recovery (tc))
1515 tcp_cc_rcv_ack (tc, rs);
1517 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
1521 * Check if duplicate ack as per RFC5681 Sec. 2
1524 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
1527 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
1528 && seq_gt (tc->snd_nxt, tc->snd_una)
1529 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
1530 && (prev_snd_wnd == tc->snd_wnd));
1534 * Checks if ack is a congestion control event.
1537 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
1538 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
1540 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
1541 * defined to be 'duplicate' as well */
1542 *is_dack = tc->sack_sb.last_sacked_bytes
1543 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
1545 /* If reneging, wait for timer based retransmits */
1546 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
1549 return (*is_dack || tcp_in_cong_recovery (tc));
1553 * Process incoming ACK
1556 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1557 tcp_header_t * th, u32 * error)
1559 u32 prev_snd_wnd, prev_snd_una;
1560 tcp_rate_sample_t rs = { 0 };
1563 TCP_EVT (TCP_EVT_CC_STAT, tc);
1565 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1566 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1568 /* We've probably entered recovery and the peer still has some
1569 * of the data we've sent. Update snd_nxt and accept the ack */
1570 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1571 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1573 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1577 tc->errors.above_ack_wnd += 1;
1578 *error = TCP_ERROR_ACK_FUTURE;
1579 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1583 /* If old ACK, probably it's an old dupack */
1584 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1586 tc->errors.below_ack_wnd += 1;
1587 *error = TCP_ERROR_ACK_OLD;
1588 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1589 if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1590 tcp_cc_handle_event (tc, 0, 1);
1591 /* Don't drop yet */
1598 * Looks okay, process feedback
1601 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1602 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1604 prev_snd_wnd = tc->snd_wnd;
1605 prev_snd_una = tc->snd_una;
1606 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1607 vnet_buffer (b)->tcp.ack_number,
1608 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1609 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1610 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1611 tcp_validate_txf_size (tc, tc->bytes_acked);
1613 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1614 tcp_bt_sample_delivery_rate (tc, &rs);
1616 tcp_program_dequeue (wrk, tc);
1618 if (tc->bytes_acked)
1619 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1621 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1624 * Check if we have congestion event
1627 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1629 tcp_cc_handle_event (tc, &rs, is_dack);
1630 tc->dupacks_in += is_dack;
1631 if (!tcp_in_cong_recovery (tc))
1633 *error = TCP_ERROR_ACK_OK;
1636 *error = TCP_ERROR_ACK_DUP;
1637 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1643 * Update congestion control (slow start/congestion avoidance)
1645 tcp_cc_update (tc, &rs);
1646 *error = TCP_ERROR_ACK_OK;
1651 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1653 if (!tcp_disconnect_pending (tc))
1655 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1656 tcp_disconnect_pending_on (tc);
1661 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1663 u32 thread_index, *pending_disconnects;
1664 tcp_connection_t *tc;
1667 if (!vec_len (wrk->pending_disconnects))
1670 thread_index = wrk->vm->thread_index;
1671 pending_disconnects = wrk->pending_disconnects;
1672 for (i = 0; i < vec_len (pending_disconnects); i++)
1674 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1675 tcp_disconnect_pending_off (tc);
1676 session_transport_closing_notify (&tc->connection);
1678 _vec_len (wrk->pending_disconnects) = 0;
1682 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1685 /* Reject out-of-order fins */
1686 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1689 /* Account for the FIN and send ack */
1691 tc->flags |= TCP_CONN_FINRCVD;
1692 tcp_program_ack (tc);
1693 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1694 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1695 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1696 tcp_program_disconnect (wrk, tc);
1697 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1698 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1699 *error = TCP_ERROR_FIN_RCVD;
1702 #ifndef CLIB_MARCH_VARIANT
1704 tcp_sack_vector_is_sane (sack_block_t * sacks)
1707 for (i = 1; i < vec_len (sacks); i++)
1709 if (sacks[i - 1].end == sacks[i].start)
1716 * Build SACK list as per RFC2018.
1718 * Makes sure the first block contains the segment that generated the current
1719 * ACK and the following ones are the ones most recently reported in SACK
1722 * @param tc TCP connection for which the SACK list is updated
1723 * @param start Start sequence number of the newest SACK block
1724 * @param end End sequence of the newest SACK block
1727 tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1729 sack_block_t *new_list = tc->snd_sacks_fl, *block = 0;
1732 /* If the first segment is ooo add it to the list. Last write might've moved
1733 * rcv_nxt over the first segment. */
1734 if (seq_lt (tc->rcv_nxt, start))
1736 vec_add2 (new_list, block, 1);
1737 block->start = start;
1741 /* Find the blocks still worth keeping. */
1742 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1744 /* Discard if rcv_nxt advanced beyond current block */
1745 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
1748 /* Merge or drop if segment overlapped by the new segment */
1749 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1750 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1752 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1753 new_list[0].start = tc->snd_sacks[i].start;
1754 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1755 new_list[0].end = tc->snd_sacks[i].end;
1759 /* Save to new SACK list if we have space. */
1760 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1761 vec_add1 (new_list, tc->snd_sacks[i]);
1764 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
1766 /* Replace old vector with new one */
1767 vec_reset_length (tc->snd_sacks);
1768 tc->snd_sacks_fl = tc->snd_sacks;
1769 tc->snd_sacks = new_list;
1771 /* Segments should not 'touch' */
1772 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
1776 tcp_sack_list_bytes (tcp_connection_t * tc)
1779 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1780 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1783 #endif /* CLIB_MARCH_VARIANT */
1785 /** Enqueue data for delivery to application */
1787 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1790 int written, error = TCP_ERROR_ENQUEUED;
1792 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1794 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1795 1 /* queue event */ , 1);
1796 tc->bytes_in += written;
1798 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1800 /* Update rcv_nxt */
1801 if (PREDICT_TRUE (written == data_len))
1803 tc->rcv_nxt += written;
1805 /* If more data written than expected, account for out-of-order bytes. */
1806 else if (written > data_len)
1808 tc->rcv_nxt += written;
1809 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1811 else if (written > 0)
1813 /* We've written something but FIFO is probably full now */
1814 tc->rcv_nxt += written;
1815 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1819 return TCP_ERROR_FIFO_FULL;
1822 /* Update SACK list if need be */
1823 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1825 /* Remove SACK blocks that have been delivered */
1826 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1832 /** Enqueue out-of-order data */
1834 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1840 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1843 /* Enqueue out-of-order data with relative offset */
1844 rv = session_enqueue_stream_connection (&tc->connection, b,
1845 vnet_buffer (b)->tcp.seq_number -
1846 tc->rcv_nxt, 0 /* queue event */ ,
1849 /* Nothing written */
1852 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1853 return TCP_ERROR_FIFO_FULL;
1856 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1857 tc->bytes_in += data_len;
1859 /* Update SACK list if in use */
1860 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1862 ooo_segment_t *newest;
1865 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1867 /* Get the newest segment from the fifo */
1868 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1871 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1872 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1873 start = tc->rcv_nxt + offset;
1874 end = start + ooo_segment_length (s0->rx_fifo, newest);
1875 tcp_update_sack_list (tc, start, end);
1876 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1877 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1881 return TCP_ERROR_ENQUEUED_OOO;
1885 * Check if ACK could be delayed. If ack can be delayed, it should return
1886 * true for a full frame. If we're always acking return 0.
1889 tcp_can_delack (tcp_connection_t * tc)
1891 /* Send ack if ... */
1893 /* just sent a rcv wnd 0
1894 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1895 /* constrained to send ack */
1896 || (tc->flags & TCP_CONN_SNDACK) != 0
1897 /* we're almost out of tx wnd */
1898 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1905 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1907 u32 discard, first = b->current_length;
1908 vlib_main_t *vm = vlib_get_main ();
1910 /* Handle multi-buffer segments */
1911 if (n_bytes_to_drop > b->current_length)
1913 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1917 discard = clib_min (n_bytes_to_drop, b->current_length);
1918 vlib_buffer_advance (b, discard);
1919 b = vlib_get_buffer (vm, b->next_buffer);
1920 n_bytes_to_drop -= discard;
1922 while (n_bytes_to_drop);
1923 if (n_bytes_to_drop > first)
1924 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1927 vlib_buffer_advance (b, n_bytes_to_drop);
1928 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1933 * Receive buffer for connection and handle acks
1935 * It handles both in order or out-of-order data.
1938 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1941 u32 error, n_bytes_to_drop, n_data_bytes;
1943 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1944 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1945 ASSERT (n_data_bytes);
1946 tc->data_segs_in += 1;
1948 /* Handle out-of-order data */
1949 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1951 /* Old sequence numbers allowed through because they overlapped
1953 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1955 /* Completely in the past (possible retransmit). Ack
1956 * retransmissions since we may not have any data to send */
1957 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1959 tcp_program_ack (tc);
1960 error = TCP_ERROR_SEGMENT_OLD;
1964 /* Chop off the bytes in the past and see if what is left
1965 * can be enqueued in order */
1966 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1967 n_data_bytes -= n_bytes_to_drop;
1968 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1969 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1971 error = TCP_ERROR_SEGMENT_OLD;
1977 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1978 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1979 tcp_program_dupack (tc);
1980 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1981 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1982 tc->rcv_las + tc->rcv_wnd);
1988 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1989 * segments can be enqueued after fifo tail offset changes. */
1990 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1991 if (tcp_can_delack (tc))
1993 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1994 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
1998 tcp_program_ack (tc);
2006 tcp_header_t tcp_header;
2007 tcp_connection_t tcp_connection;
2011 format_tcp_rx_trace (u8 * s, va_list * args)
2013 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2014 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2015 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2016 u32 indent = format_get_indent (s);
2018 s = format (s, "%U\n%U%U",
2019 format_tcp_header, &t->tcp_header, 128,
2020 format_white_space, indent,
2021 format_tcp_connection, &t->tcp_connection, 1);
2027 format_tcp_rx_trace_short (u8 * s, va_list * args)
2029 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2030 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2031 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2033 s = format (s, "%d -> %d (%U)",
2034 clib_net_to_host_u16 (t->tcp_header.dst_port),
2035 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
2036 t->tcp_connection.state);
2042 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
2043 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
2047 clib_memcpy_fast (&t0->tcp_connection, tc0,
2048 sizeof (t0->tcp_connection));
2052 th0 = tcp_buffer_hdr (b0);
2054 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2058 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2059 vlib_frame_t * frame, u8 is_ip4)
2063 n_left = frame->n_vectors;
2064 from = vlib_frame_vector_args (frame);
2068 tcp_connection_t *tc0;
2075 b0 = vlib_get_buffer (vm, bi0);
2077 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2079 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2080 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2082 th0 = tcp_buffer_hdr (b0);
2083 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2092 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2093 u8 is_ip4, u32 evt, u32 val)
2096 vlib_node_increment_counter (vm, tcp4_node, evt, val);
2098 vlib_node_increment_counter (vm, tcp6_node, evt, val);
2101 #define tcp_maybe_inc_counter(node_id, err, count) \
2103 if (next0 != tcp_next_drop (is_ip4)) \
2104 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2105 tcp6_##node_id##_node.index, is_ip4, err, \
2108 #define tcp_inc_counter(node_id, err, count) \
2109 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2110 tcp6_##node_id##_node.index, is_ip4, \
2112 #define tcp_maybe_inc_err_counter(cnts, err) \
2114 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2116 #define tcp_inc_err_counter(cnts, err, val) \
2120 #define tcp_store_err_counters(node_id, cnts) \
2123 for (i = 0; i < TCP_N_ERROR; i++) \
2125 tcp_inc_counter(node_id, i, cnts[i]); \
2130 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2131 vlib_frame_t * frame, int is_ip4)
2133 u32 thread_index = vm->thread_index, errors = 0;
2134 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2135 u32 n_left_from, *from, *first_buffer;
2136 u16 err_counters[TCP_N_ERROR] = { 0 };
2138 if (node->flags & VLIB_NODE_FLAG_TRACE)
2139 tcp_established_trace_frame (vm, node, frame, is_ip4);
2141 first_buffer = from = vlib_frame_vector_args (frame);
2142 n_left_from = frame->n_vectors;
2144 while (n_left_from > 0)
2146 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2149 tcp_connection_t *tc0;
2151 if (n_left_from > 1)
2154 pb = vlib_get_buffer (vm, from[1]);
2155 vlib_prefetch_buffer_header (pb, LOAD);
2156 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2163 b0 = vlib_get_buffer (vm, bi0);
2164 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2167 if (PREDICT_FALSE (tc0 == 0))
2169 error0 = TCP_ERROR_INVALID_CONNECTION;
2173 th0 = tcp_buffer_hdr (b0);
2175 /* TODO header prediction fast path */
2177 /* 1-4: check SEQ, RST, SYN */
2178 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2180 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2184 /* 5: check the ACK field */
2185 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2188 /* 6: check the URG bit TODO */
2190 /* 7: process the segment text */
2191 if (vnet_buffer (b0)->tcp.data_len)
2192 error0 = tcp_segment_rcv (wrk, tc0, b0);
2194 /* 8: check the FIN bit */
2195 if (PREDICT_FALSE (tcp_is_fin (th0)))
2196 tcp_rcv_fin (wrk, tc0, b0, &error0);
2199 tcp_inc_err_counter (err_counters, error0, 1);
2202 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2204 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
2205 tcp_store_err_counters (established, err_counters);
2206 tcp_handle_postponed_dequeues (wrk);
2207 tcp_handle_disconnects (wrk);
2208 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
2210 return frame->n_vectors;
2213 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
2214 vlib_node_runtime_t * node,
2215 vlib_frame_t * from_frame)
2217 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2220 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
2221 vlib_node_runtime_t * node,
2222 vlib_frame_t * from_frame)
2224 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2228 VLIB_REGISTER_NODE (tcp4_established_node) =
2230 .name = "tcp4-established",
2231 /* Takes a vector of packets. */
2232 .vector_size = sizeof (u32),
2233 .n_errors = TCP_N_ERROR,
2234 .error_strings = tcp_error_strings,
2235 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2238 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2239 foreach_tcp_state_next
2242 .format_trace = format_tcp_rx_trace_short,
2247 VLIB_REGISTER_NODE (tcp6_established_node) =
2249 .name = "tcp6-established",
2250 /* Takes a vector of packets. */
2251 .vector_size = sizeof (u32),
2252 .n_errors = TCP_N_ERROR,
2253 .error_strings = tcp_error_strings,
2254 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2257 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2258 foreach_tcp_state_next
2261 .format_trace = format_tcp_rx_trace_short,
2267 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
2270 transport_connection_t *tmp = 0;
2277 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2280 u8 is_ip_valid = 0, val_l, val_r;
2282 if (tc->connection.is_ip4)
2284 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
2286 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
2287 &tc->connection.lcl_ip.ip4);
2288 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
2289 val_r = !ip4_address_compare (&ip4_hdr->src_address,
2290 &tc->connection.rmt_ip.ip4);
2291 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2292 is_ip_valid = val_l && val_r;
2296 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
2298 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
2299 &tc->connection.lcl_ip.ip6);
2300 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
2301 val_r = !ip6_address_compare (&ip6_hdr->src_address,
2302 &tc->connection.rmt_ip.ip6);
2303 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2304 is_ip_valid = val_l && val_r;
2307 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2308 && (tc->state == TCP_STATE_LISTEN
2309 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
2313 handle = session_lookup_half_open_handle (&tc->connection);
2314 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
2315 tc->c_proto, tc->c_is_ip4);
2319 if (tmp->lcl_port == hdr->dst_port
2320 && tmp->rmt_port == hdr->src_port)
2322 TCP_DBG ("half-open is valid!");
2331 * Lookup transport connection
2333 static tcp_connection_t *
2334 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2338 transport_connection_t *tconn;
2339 tcp_connection_t *tc;
2344 ip4 = vlib_buffer_get_current (b);
2345 tcp = ip4_next_header (ip4);
2346 tconn = session_lookup_connection_wt4 (fib_index,
2351 TRANSPORT_PROTO_TCP,
2352 thread_index, &is_filtered);
2353 tc = tcp_get_connection_from_transport (tconn);
2354 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2359 ip6 = vlib_buffer_get_current (b);
2360 tcp = ip6_next_header (ip6);
2361 tconn = session_lookup_connection_wt6 (fib_index,
2366 TRANSPORT_PROTO_TCP,
2367 thread_index, &is_filtered);
2368 tc = tcp_get_connection_from_transport (tconn);
2369 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2375 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
2377 vnet_main_t *vnm = vnet_get_main ();
2378 const dpo_id_t *dpo;
2379 const load_balance_t *lb;
2380 vnet_hw_interface_t *hw_if;
2381 u32 sw_if_idx, lb_idx;
2385 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
2386 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
2390 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
2391 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
2394 lb = load_balance_get (lb_idx);
2395 dpo = load_balance_get_bucket_i (lb, 0);
2397 sw_if_idx = dpo->dpoi_index;
2398 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
2400 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
2401 tc->cfg_flags |= TCP_CFG_F_TSO;
2405 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2406 vlib_frame_t * from_frame, int is_ip4)
2408 u32 n_left_from, *from, *first_buffer, errors = 0;
2409 u32 my_thread_index = vm->thread_index;
2410 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2412 from = first_buffer = vlib_frame_vector_args (from_frame);
2413 n_left_from = from_frame->n_vectors;
2415 while (n_left_from > 0)
2417 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2418 tcp_connection_t *tc0, *new_tc0;
2419 tcp_header_t *tcp0 = 0;
2427 b0 = vlib_get_buffer (vm, bi0);
2429 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2430 if (PREDICT_FALSE (tc0 == 0))
2432 error0 = TCP_ERROR_INVALID_CONNECTION;
2436 /* Half-open completed recently but the connection was't removed
2437 * yet by the owning thread */
2438 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2440 /* Make sure the connection actually exists */
2441 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2442 my_thread_index, is_ip4));
2443 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2447 ack0 = vnet_buffer (b0)->tcp.ack_number;
2448 seq0 = vnet_buffer (b0)->tcp.seq_number;
2449 tcp0 = tcp_buffer_hdr (b0);
2451 /* Crude check to see if the connection handle does not match
2452 * the packet. Probably connection just switched to established */
2453 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2454 || tcp0->src_port != tc0->c_rmt_port))
2456 error0 = TCP_ERROR_INVALID_CONNECTION;
2460 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2461 && !tcp_syn (tcp0)))
2463 error0 = TCP_ERROR_SEGMENT_INVALID;
2467 /* SYNs consume sequence numbers */
2468 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2471 * 1. check the ACK bit
2475 * If the ACK bit is set
2476 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2477 * the RST bit is set, if so drop the segment and return)
2478 * <SEQ=SEG.ACK><CTL=RST>
2479 * and discard the segment. Return.
2480 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2484 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2486 if (!tcp_rst (tcp0))
2487 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2488 error0 = TCP_ERROR_RCV_WND;
2492 /* Make sure ACK is valid */
2493 if (seq_gt (tc0->snd_una, ack0))
2495 error0 = TCP_ERROR_ACK_INVALID;
2501 * 2. check the RST bit
2506 /* If ACK is acceptable, signal client that peer is not
2507 * willing to accept connection and drop connection*/
2509 tcp_connection_reset (tc0);
2510 error0 = TCP_ERROR_RST_RCVD;
2515 * 3. check the security and precedence (skipped)
2519 * 4. check the SYN bit
2522 /* No SYN flag. Drop. */
2523 if (!tcp_syn (tcp0))
2525 error0 = TCP_ERROR_SEGMENT_INVALID;
2530 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2532 error0 = TCP_ERROR_OPTIONS;
2536 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2537 * current thread pool. */
2538 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2539 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2540 new_tc0->irs = seq0;
2541 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2542 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2544 /* If this is not the owning thread, wait for syn retransmit to
2545 * expire and cleanup then */
2546 if (tcp_half_open_connection_cleanup (tc0))
2547 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2549 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2551 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2552 new_tc0->tsval_recent_age = tcp_time_now ();
2555 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2556 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2558 new_tc0->rcv_wscale = 0;
2560 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2561 << new_tc0->snd_wscale;
2562 new_tc0->snd_wl1 = seq0;
2563 new_tc0->snd_wl2 = ack0;
2565 tcp_connection_init_vars (new_tc0);
2567 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2568 if (PREDICT_TRUE (tcp_ack (tcp0)))
2570 /* Our SYN is ACKed: we have iss < ack = snd_una */
2572 /* TODO Dequeue acknowledged segments if we support Fast Open */
2573 new_tc0->snd_una = ack0;
2574 new_tc0->state = TCP_STATE_ESTABLISHED;
2576 /* Make sure las is initialized for the wnd computation */
2577 new_tc0->rcv_las = new_tc0->rcv_nxt;
2579 /* Notify app that we have connection. If session layer can't
2580 * allocate session send reset */
2581 if (session_stream_connect_notify (&new_tc0->connection, 0))
2583 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2584 tcp_connection_cleanup (new_tc0);
2585 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2589 new_tc0->tx_fifo_size =
2590 transport_tx_fifo_size (&new_tc0->connection);
2591 /* Update rtt with the syn-ack sample */
2592 tcp_estimate_initial_rtt (new_tc0);
2593 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2594 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2596 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2599 new_tc0->state = TCP_STATE_SYN_RCVD;
2601 /* Notify app that we have connection */
2602 if (session_stream_connect_notify (&new_tc0->connection, 0))
2604 tcp_connection_cleanup (new_tc0);
2605 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2606 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2607 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2611 new_tc0->tx_fifo_size =
2612 transport_tx_fifo_size (&new_tc0->connection);
2613 new_tc0->rtt_ts = 0;
2614 tcp_init_snd_vars (new_tc0);
2615 tcp_send_synack (new_tc0);
2616 error0 = TCP_ERROR_SYNS_RCVD;
2620 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2621 tcp_check_tx_offload (new_tc0, is_ip4);
2623 /* Read data, if any */
2624 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2626 clib_warning ("rcvd data in syn-sent");
2627 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2628 if (error0 == TCP_ERROR_ACK_OK)
2629 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2633 /* Send ack now instead of programming it because connection was
2634 * just established and it's not optional. */
2635 tcp_send_ack (new_tc0);
2640 tcp_inc_counter (syn_sent, error0, 1);
2641 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2643 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2644 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2645 clib_memcpy_fast (&t0->tcp_connection, tc0,
2646 sizeof (t0->tcp_connection));
2650 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2652 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2653 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2655 return from_frame->n_vectors;
2658 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2659 vlib_node_runtime_t * node,
2660 vlib_frame_t * from_frame)
2662 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2665 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2666 vlib_node_runtime_t * node,
2667 vlib_frame_t * from_frame)
2669 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2673 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2675 .name = "tcp4-syn-sent",
2676 /* Takes a vector of packets. */
2677 .vector_size = sizeof (u32),
2678 .n_errors = TCP_N_ERROR,
2679 .error_strings = tcp_error_strings,
2680 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2683 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2684 foreach_tcp_state_next
2687 .format_trace = format_tcp_rx_trace_short,
2692 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2694 .name = "tcp6-syn-sent",
2695 /* Takes a vector of packets. */
2696 .vector_size = sizeof (u32),
2697 .n_errors = TCP_N_ERROR,
2698 .error_strings = tcp_error_strings,
2699 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2702 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2703 foreach_tcp_state_next
2706 .format_trace = format_tcp_rx_trace_short,
2711 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2712 * as per RFC793 p. 64
2715 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2716 vlib_frame_t * from_frame, int is_ip4)
2718 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2719 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2720 u32 n_left_from, *from, max_dequeue;
2722 from = first_buffer = vlib_frame_vector_args (from_frame);
2723 n_left_from = from_frame->n_vectors;
2725 while (n_left_from > 0)
2727 u32 bi0, error0 = TCP_ERROR_NONE;
2728 tcp_header_t *tcp0 = 0;
2729 tcp_connection_t *tc0;
2737 b0 = vlib_get_buffer (vm, bi0);
2738 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2740 if (PREDICT_FALSE (tc0 == 0))
2742 error0 = TCP_ERROR_INVALID_CONNECTION;
2746 tcp0 = tcp_buffer_hdr (b0);
2747 is_fin0 = tcp_is_fin (tcp0);
2751 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2753 tcp_connection_t *tmp;
2754 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2756 if (tmp->state != tc0->state)
2758 if (tc0->state != TCP_STATE_CLOSED)
2759 clib_warning ("state changed");
2766 * Special treatment for CLOSED
2768 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2770 error0 = TCP_ERROR_CONNECTION_CLOSED;
2775 * For all other states (except LISTEN)
2778 /* 1-4: check SEQ, RST, SYN */
2779 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2782 /* 5: check the ACK field */
2785 case TCP_STATE_SYN_RCVD:
2787 /* Make sure the segment is exactly right */
2788 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2790 tcp_connection_reset (tc0);
2791 error0 = TCP_ERROR_SEGMENT_INVALID;
2796 * If the segment acknowledgment is not acceptable, form a
2798 * <SEQ=SEG.ACK><CTL=RST>
2801 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2803 tcp_connection_reset (tc0);
2807 /* Update rtt and rto */
2808 tcp_estimate_initial_rtt (tc0);
2809 tcp_connection_tx_pacer_update (tc0);
2811 /* Switch state to ESTABLISHED */
2812 tc0->state = TCP_STATE_ESTABLISHED;
2813 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2815 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2816 tcp_check_tx_offload (tc0, is_ip4);
2818 /* Initialize session variables */
2819 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2820 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2821 << tc0->rcv_opts.wscale;
2822 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2823 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2825 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2826 tcp_retransmit_timer_reset (tc0);
2827 if (session_stream_accept_notify (&tc0->connection))
2829 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2830 tcp_connection_reset (tc0);
2833 error0 = TCP_ERROR_ACK_OK;
2835 case TCP_STATE_ESTABLISHED:
2836 /* We can get packets in established state here because they
2837 * were enqueued before state change */
2838 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2842 case TCP_STATE_FIN_WAIT_1:
2843 /* In addition to the processing for the ESTABLISHED state, if
2844 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2845 * continue processing in that state. */
2846 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2849 /* Still have to send the FIN */
2850 if (tc0->flags & TCP_CONN_FINPNDG)
2852 /* TX fifo finally drained */
2853 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2854 if (max_dequeue <= tc0->burst_acked)
2856 /* If a fin was received and data was acked extend wait */
2857 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2858 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2859 tcp_cfg.closewait_time);
2861 /* If FIN is ACKed */
2862 else if (tc0->snd_una == tc0->snd_nxt)
2864 /* Stop all retransmit timers because we have nothing more
2866 tcp_connection_timers_reset (tc0);
2868 /* We already have a FIN but didn't transition to CLOSING
2869 * because of outstanding tx data. Close the connection. */
2870 if (tc0->flags & TCP_CONN_FINRCVD)
2872 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2873 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE,
2874 tcp_cfg.cleanup_time);
2875 session_transport_closed_notify (&tc0->connection);
2879 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2880 /* Enable waitclose because we're willing to wait for peer's
2881 * FIN but not indefinitely. */
2882 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2884 /* Don't try to deq the FIN acked */
2885 if (tc0->burst_acked > 1)
2886 session_tx_fifo_dequeue_drop (&tc0->connection,
2887 tc0->burst_acked - 1);
2888 tc0->burst_acked = 0;
2891 case TCP_STATE_FIN_WAIT_2:
2892 /* In addition to the processing for the ESTABLISHED state, if
2893 * the retransmission queue is empty, the user's CLOSE can be
2894 * acknowledged ("ok") but do not delete the TCB. */
2895 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2897 tc0->burst_acked = 0;
2899 case TCP_STATE_CLOSE_WAIT:
2900 /* Do the same processing as for the ESTABLISHED state. */
2901 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2904 if (!(tc0->flags & TCP_CONN_FINPNDG))
2907 /* Still have outstanding tx data */
2908 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2909 if (max_dequeue > tc0->burst_acked)
2913 tcp_connection_timers_reset (tc0);
2914 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2915 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2917 case TCP_STATE_CLOSING:
2918 /* In addition to the processing for the ESTABLISHED state, if
2919 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2920 * otherwise ignore the segment. */
2921 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2924 if (tc0->snd_una != tc0->snd_nxt)
2927 tcp_connection_timers_reset (tc0);
2928 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2929 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2930 session_transport_closed_notify (&tc0->connection);
2934 case TCP_STATE_LAST_ACK:
2935 /* The only thing that [should] arrive in this state is an
2936 * acknowledgment of our FIN. If our FIN is now acknowledged,
2937 * delete the TCB, enter the CLOSED state, and return. */
2939 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2942 /* Apparently our ACK for the peer's FIN was lost */
2943 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2949 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2950 session_transport_closed_notify (&tc0->connection);
2952 /* Don't free the connection from the data path since
2953 * we can't ensure that we have no packets already enqueued
2954 * to output. Rely instead on the waitclose timer */
2955 tcp_connection_timers_reset (tc0);
2956 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
2961 case TCP_STATE_TIME_WAIT:
2962 /* The only thing that can arrive in this state is a
2963 * retransmission of the remote FIN. Acknowledge it, and restart
2964 * the 2 MSL timeout. */
2966 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2972 tcp_program_ack (tc0);
2973 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2981 /* 6: check the URG bit TODO */
2983 /* 7: process the segment text */
2986 case TCP_STATE_ESTABLISHED:
2987 case TCP_STATE_FIN_WAIT_1:
2988 case TCP_STATE_FIN_WAIT_2:
2989 if (vnet_buffer (b0)->tcp.data_len)
2990 error0 = tcp_segment_rcv (wrk, tc0, b0);
2992 case TCP_STATE_CLOSE_WAIT:
2993 case TCP_STATE_CLOSING:
2994 case TCP_STATE_LAST_ACK:
2995 case TCP_STATE_TIME_WAIT:
2996 /* This should not occur, since a FIN has been received from the
2997 * remote side. Ignore the segment text. */
3001 /* 8: check the FIN bit */
3005 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
3009 case TCP_STATE_ESTABLISHED:
3010 /* Account for the FIN and send ack */
3012 tcp_program_ack (tc0);
3013 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
3014 tcp_program_disconnect (wrk, tc0);
3015 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
3017 case TCP_STATE_SYN_RCVD:
3018 /* Send FIN-ACK, enter LAST-ACK and because the app was not
3019 * notified yet, set a cleanup timer instead of relying on
3020 * disconnect notify and the implicit close call. */
3021 tcp_connection_timers_reset (tc0);
3024 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3025 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3027 case TCP_STATE_CLOSE_WAIT:
3028 case TCP_STATE_CLOSING:
3029 case TCP_STATE_LAST_ACK:
3032 case TCP_STATE_FIN_WAIT_1:
3035 if (tc0->flags & TCP_CONN_FINPNDG)
3037 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
3038 * sending it. Since we already received a fin, do not wait
3040 tc0->flags |= TCP_CONN_FINRCVD;
3041 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3042 tcp_cfg.closewait_time);
3046 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
3047 tcp_program_ack (tc0);
3048 /* Wait for ACK for our FIN but not forever */
3049 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3050 tcp_cfg.closing_time);
3053 case TCP_STATE_FIN_WAIT_2:
3054 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
3056 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3057 tcp_connection_timers_reset (tc0);
3058 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3059 tcp_program_ack (tc0);
3060 session_transport_closed_notify (&tc0->connection);
3062 case TCP_STATE_TIME_WAIT:
3063 /* Remain in the TIME-WAIT state. Restart the time-wait
3066 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3069 error0 = TCP_ERROR_FIN_RCVD;
3073 tcp_inc_counter (rcv_process, error0, 1);
3074 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3076 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3077 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
3081 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
3083 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
3084 tcp_handle_postponed_dequeues (wrk);
3085 tcp_handle_disconnects (wrk);
3086 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3088 return from_frame->n_vectors;
3091 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
3092 vlib_node_runtime_t * node,
3093 vlib_frame_t * from_frame)
3095 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3098 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
3099 vlib_node_runtime_t * node,
3100 vlib_frame_t * from_frame)
3102 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3106 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
3108 .name = "tcp4-rcv-process",
3109 /* Takes a vector of packets. */
3110 .vector_size = sizeof (u32),
3111 .n_errors = TCP_N_ERROR,
3112 .error_strings = tcp_error_strings,
3113 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3116 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3117 foreach_tcp_state_next
3120 .format_trace = format_tcp_rx_trace_short,
3125 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3127 .name = "tcp6-rcv-process",
3128 /* Takes a vector of packets. */
3129 .vector_size = sizeof (u32),
3130 .n_errors = TCP_N_ERROR,
3131 .error_strings = tcp_error_strings,
3132 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3135 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3136 foreach_tcp_state_next
3139 .format_trace = format_tcp_rx_trace_short,
3144 * LISTEN state processing as per RFC 793 p. 65
3147 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3148 vlib_frame_t * from_frame, int is_ip4)
3150 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3151 u32 my_thread_index = vm->thread_index;
3153 from = first_buffer = vlib_frame_vector_args (from_frame);
3154 n_left_from = from_frame->n_vectors;
3156 while (n_left_from > 0)
3161 tcp_header_t *th0 = 0;
3162 tcp_connection_t *lc0;
3165 tcp_connection_t *child0;
3166 u32 error0 = TCP_ERROR_NONE;
3172 b0 = vlib_get_buffer (vm, bi0);
3173 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3177 ip40 = vlib_buffer_get_current (b0);
3178 th0 = ip4_next_header (ip40);
3182 ip60 = vlib_buffer_get_current (b0);
3183 th0 = ip6_next_header (ip60);
3186 /* Create child session. For syn-flood protection use filter */
3188 /* 1. first check for an RST: handled in dispatch */
3189 /* if (tcp_rst (th0))
3193 /* 2. second check for an ACK: handled in dispatch */
3194 /* if (tcp_ack (th0))
3196 tcp_send_reset (b0, is_ip4);
3201 /* 3. check for a SYN (did that already) */
3203 /* Make sure connection wasn't just created */
3204 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3206 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3208 error0 = TCP_ERROR_CREATE_EXISTS;
3212 /* Create child session and send SYN-ACK */
3213 child0 = tcp_connection_alloc (my_thread_index);
3214 child0->c_lcl_port = th0->dst_port;
3215 child0->c_rmt_port = th0->src_port;
3216 child0->c_is_ip4 = is_ip4;
3217 child0->state = TCP_STATE_SYN_RCVD;
3218 child0->c_fib_index = lc0->c_fib_index;
3219 child0->cc_algo = lc0->cc_algo;
3223 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3224 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3228 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3229 sizeof (ip6_address_t));
3230 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3231 sizeof (ip6_address_t));
3234 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3236 error0 = TCP_ERROR_OPTIONS;
3237 tcp_connection_free (child0);
3241 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3242 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3243 child0->rcv_las = child0->rcv_nxt;
3244 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3246 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3247 * segments are used to initialize PAWS. */
3248 if (tcp_opts_tstamp (&child0->rcv_opts))
3250 child0->tsval_recent = child0->rcv_opts.tsval;
3251 child0->tsval_recent_age = tcp_time_now ();
3254 if (tcp_opts_wscale (&child0->rcv_opts))
3255 child0->snd_wscale = child0->rcv_opts.wscale;
3257 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3258 << child0->snd_wscale;
3259 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3260 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3262 tcp_connection_init_vars (child0);
3263 child0->rto = TCP_RTO_MIN;
3265 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3266 lc0->c_thread_index, 0 /* notify */ ))
3268 tcp_connection_cleanup (child0);
3269 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3273 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3274 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3275 tcp_send_synack (child0);
3279 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3281 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3282 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3283 clib_memcpy_fast (&t0->tcp_connection, lc0,
3284 sizeof (t0->tcp_connection));
3287 n_syns += (error0 == TCP_ERROR_NONE);
3290 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3291 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3293 return from_frame->n_vectors;
3296 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3297 vlib_frame_t * from_frame)
3299 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3302 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3303 vlib_frame_t * from_frame)
3305 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3309 VLIB_REGISTER_NODE (tcp4_listen_node) =
3311 .name = "tcp4-listen",
3312 /* Takes a vector of packets. */
3313 .vector_size = sizeof (u32),
3314 .n_errors = TCP_N_ERROR,
3315 .error_strings = tcp_error_strings,
3316 .n_next_nodes = TCP_LISTEN_N_NEXT,
3319 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3320 foreach_tcp_state_next
3323 .format_trace = format_tcp_rx_trace_short,
3328 VLIB_REGISTER_NODE (tcp6_listen_node) =
3330 .name = "tcp6-listen",
3331 /* Takes a vector of packets. */
3332 .vector_size = sizeof (u32),
3333 .n_errors = TCP_N_ERROR,
3334 .error_strings = tcp_error_strings,
3335 .n_next_nodes = TCP_LISTEN_N_NEXT,
3338 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3339 foreach_tcp_state_next
3342 .format_trace = format_tcp_rx_trace_short,
3346 typedef enum _tcp_input_next
3348 TCP_INPUT_NEXT_DROP,
3349 TCP_INPUT_NEXT_LISTEN,
3350 TCP_INPUT_NEXT_RCV_PROCESS,
3351 TCP_INPUT_NEXT_SYN_SENT,
3352 TCP_INPUT_NEXT_ESTABLISHED,
3353 TCP_INPUT_NEXT_RESET,
3354 TCP_INPUT_NEXT_PUNT,
3358 #define foreach_tcp4_input_next \
3359 _ (DROP, "ip4-drop") \
3360 _ (LISTEN, "tcp4-listen") \
3361 _ (RCV_PROCESS, "tcp4-rcv-process") \
3362 _ (SYN_SENT, "tcp4-syn-sent") \
3363 _ (ESTABLISHED, "tcp4-established") \
3364 _ (RESET, "tcp4-reset") \
3365 _ (PUNT, "ip4-punt")
3367 #define foreach_tcp6_input_next \
3368 _ (DROP, "ip6-drop") \
3369 _ (LISTEN, "tcp6-listen") \
3370 _ (RCV_PROCESS, "tcp6-rcv-process") \
3371 _ (SYN_SENT, "tcp6-syn-sent") \
3372 _ (ESTABLISHED, "tcp6-established") \
3373 _ (RESET, "tcp6-reset") \
3374 _ (PUNT, "ip6-punt")
3376 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3379 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3380 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3382 tcp_connection_t *tc;
3387 for (i = 0; i < n_bufs; i++)
3389 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3391 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3392 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3394 tcp = vlib_buffer_get_current (bs[i]);
3395 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3401 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3403 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3405 *next = TCP_INPUT_NEXT_DROP;
3407 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3409 *next = TCP_INPUT_NEXT_PUNT;
3410 *error = TCP_ERROR_PUNT;
3414 *next = TCP_INPUT_NEXT_RESET;
3415 *error = TCP_ERROR_NO_LISTENER;
3419 always_inline tcp_connection_t *
3420 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3421 u8 is_ip4, u8 is_nolookup)
3423 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3424 int n_advance_bytes, n_data_bytes;
3425 transport_connection_t *tc;
3431 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3432 int ip_hdr_bytes = ip4_header_bytes (ip4);
3433 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3435 *error = TCP_ERROR_LENGTH;
3438 tcp = ip4_next_header (ip4);
3439 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3440 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3441 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3443 /* Length check. Checksum computed by ipx_local no need to compute again */
3444 if (PREDICT_FALSE (n_data_bytes < 0))
3446 *error = TCP_ERROR_LENGTH;
3451 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3452 &ip4->src_address, tcp->dst_port,
3454 TRANSPORT_PROTO_TCP, thread_index,
3459 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3460 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3462 *error = TCP_ERROR_LENGTH;
3465 tcp = ip6_next_header (ip6);
3466 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3467 n_advance_bytes = tcp_header_bytes (tcp);
3468 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3470 n_advance_bytes += sizeof (ip6[0]);
3472 if (PREDICT_FALSE (n_data_bytes < 0))
3474 *error = TCP_ERROR_LENGTH;
3481 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3483 ip4_main_t *im = &ip4_main;
3484 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3485 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3488 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3490 tcp->dst_port, tcp->src_port,
3491 TRANSPORT_PROTO_TCP,
3492 thread_index, &result);
3498 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3499 tcp.connection_index,
3502 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3503 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3504 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3505 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3506 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3508 vnet_buffer (b)->tcp.flags = 0;
3510 *error = result ? TCP_ERROR_NONE + result : *error;
3512 return tcp_get_connection_from_transport (tc);
3516 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3517 vlib_buffer_t * b, u16 * next, u32 * error)
3522 tcp = tcp_buffer_hdr (b);
3523 flags = tcp->flags & filter_flags;
3524 *next = tm->dispatch_table[tc->state][flags].next;
3525 *error = tm->dispatch_table[tc->state][flags].error;
3528 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3529 || *next == TCP_INPUT_NEXT_RESET))
3531 /* Overload tcp flags to store state */
3532 tcp_state_t state = tc->state;
3533 vnet_buffer (b)->tcp.flags = tc->state;
3535 if (*error == TCP_ERROR_DISPATCH)
3536 clib_warning ("tcp conn %u disp error state %U flags %U",
3537 tc->c_c_index, format_tcp_state, state,
3538 format_tcp_flags, (int) flags);
3543 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3544 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3546 u32 n_left_from, *from, thread_index = vm->thread_index;
3547 tcp_main_t *tm = vnet_get_tcp_main ();
3548 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3549 u16 nexts[VLIB_FRAME_SIZE], *next;
3551 tcp_set_time_now (tcp_get_worker (thread_index));
3553 from = vlib_frame_vector_args (frame);
3554 n_left_from = frame->n_vectors;
3555 vlib_get_buffers (vm, from, bufs, n_left_from);
3560 while (n_left_from >= 4)
3562 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3563 tcp_connection_t *tc0, *tc1;
3566 vlib_prefetch_buffer_header (b[2], STORE);
3567 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3569 vlib_prefetch_buffer_header (b[3], STORE);
3570 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3573 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3575 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3577 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3580 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3582 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3583 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3585 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3586 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3588 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3589 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3593 if (PREDICT_TRUE (tc0 != 0))
3595 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3596 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3597 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3600 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3602 if (PREDICT_TRUE (tc1 != 0))
3604 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3605 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3606 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3609 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3616 while (n_left_from > 0)
3618 tcp_connection_t *tc0;
3619 u32 error0 = TCP_ERROR_NO_LISTENER;
3621 if (n_left_from > 1)
3623 vlib_prefetch_buffer_header (b[1], STORE);
3624 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3627 next[0] = TCP_INPUT_NEXT_DROP;
3628 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3630 if (PREDICT_TRUE (tc0 != 0))
3632 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3633 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3634 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3637 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3644 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3645 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3647 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3648 return frame->n_vectors;
3651 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3652 vlib_node_runtime_t * node,
3653 vlib_frame_t * from_frame)
3655 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3656 1 /* is_nolookup */ );
3659 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3660 vlib_node_runtime_t * node,
3661 vlib_frame_t * from_frame)
3663 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3664 1 /* is_nolookup */ );
3668 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3670 .name = "tcp4-input-nolookup",
3671 /* Takes a vector of packets. */
3672 .vector_size = sizeof (u32),
3673 .n_errors = TCP_N_ERROR,
3674 .error_strings = tcp_error_strings,
3675 .n_next_nodes = TCP_INPUT_N_NEXT,
3678 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3679 foreach_tcp4_input_next
3682 .format_buffer = format_tcp_header,
3683 .format_trace = format_tcp_rx_trace,
3688 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3690 .name = "tcp6-input-nolookup",
3691 /* Takes a vector of packets. */
3692 .vector_size = sizeof (u32),
3693 .n_errors = TCP_N_ERROR,
3694 .error_strings = tcp_error_strings,
3695 .n_next_nodes = TCP_INPUT_N_NEXT,
3698 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3699 foreach_tcp6_input_next
3702 .format_buffer = format_tcp_header,
3703 .format_trace = format_tcp_rx_trace,
3707 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3708 vlib_frame_t * from_frame)
3710 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3711 0 /* is_nolookup */ );
3714 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3715 vlib_frame_t * from_frame)
3717 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3718 0 /* is_nolookup */ );
3722 VLIB_REGISTER_NODE (tcp4_input_node) =
3724 .name = "tcp4-input",
3725 /* Takes a vector of packets. */
3726 .vector_size = sizeof (u32),
3727 .n_errors = TCP_N_ERROR,
3728 .error_strings = tcp_error_strings,
3729 .n_next_nodes = TCP_INPUT_N_NEXT,
3732 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3733 foreach_tcp4_input_next
3736 .format_buffer = format_tcp_header,
3737 .format_trace = format_tcp_rx_trace,
3742 VLIB_REGISTER_NODE (tcp6_input_node) =
3744 .name = "tcp6-input",
3745 /* Takes a vector of packets. */
3746 .vector_size = sizeof (u32),
3747 .n_errors = TCP_N_ERROR,
3748 .error_strings = tcp_error_strings,
3749 .n_next_nodes = TCP_INPUT_N_NEXT,
3752 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3753 foreach_tcp6_input_next
3756 .format_buffer = format_tcp_header,
3757 .format_trace = format_tcp_rx_trace,
3761 #ifndef CLIB_MARCH_VARIANT
3763 tcp_dispatch_table_init (tcp_main_t * tm)
3766 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3767 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3769 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3770 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3773 #define _(t,f,n,e) \
3775 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3776 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3779 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3780 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3781 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3782 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3783 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3784 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3785 TCP_ERROR_ACK_INVALID);
3786 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3787 TCP_ERROR_SEGMENT_INVALID);
3788 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3789 TCP_ERROR_SEGMENT_INVALID);
3790 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3791 TCP_ERROR_INVALID_CONNECTION);
3792 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3793 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3794 TCP_ERROR_SEGMENT_INVALID);
3795 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3796 TCP_ERROR_SEGMENT_INVALID);
3797 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3799 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3800 TCP_ERROR_SEGMENT_INVALID);
3801 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3802 TCP_ERROR_SEGMENT_INVALID);
3803 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3804 TCP_ERROR_SEGMENT_INVALID);
3805 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3806 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3807 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3808 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3809 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3810 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3812 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3813 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3815 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3817 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3818 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3819 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3820 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3822 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3824 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3825 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3826 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3828 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3829 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3830 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3831 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3832 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3833 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3834 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3835 /* SYN-ACK for a SYN */
3836 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3838 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3839 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3840 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3842 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3843 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3845 /* ACK for for established connection -> tcp-established. */
3846 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3847 /* FIN for for established connection -> tcp-established. */
3848 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3849 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3851 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3853 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3854 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3855 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3857 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3858 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3859 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3860 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3861 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3862 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3863 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3864 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3866 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3867 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3869 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3871 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3872 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3873 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3874 /* ACK or FIN-ACK to our FIN */
3875 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3876 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3878 /* FIN in reply to our FIN from the other side */
3879 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3880 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3881 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3883 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3884 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3885 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3886 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3887 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3888 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3889 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3891 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3892 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3893 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3894 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3896 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3898 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3899 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3900 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3901 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3903 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3904 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3905 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3906 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3908 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3910 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3911 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3912 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3913 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3915 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3916 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3918 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3920 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3921 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3922 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3924 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3925 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3926 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3927 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3928 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3929 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3930 /* FIN confirming that the peer (app) has closed */
3931 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3932 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3933 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3935 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3936 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3938 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3939 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3941 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3942 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3944 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3945 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3946 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3947 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3949 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3951 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3952 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3953 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3955 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3956 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3957 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3958 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3959 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3960 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3961 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3962 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3964 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3965 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3967 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3969 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3970 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3971 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3972 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3973 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3975 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3976 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3978 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3979 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3980 * incoming segment not containing a RST causes a RST to be sent in
3982 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3983 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3984 TCP_ERROR_CONNECTION_CLOSED);
3985 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3986 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3987 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3992 static clib_error_t *
3993 tcp_input_init (vlib_main_t * vm)
3995 clib_error_t *error = 0;
3996 tcp_main_t *tm = vnet_get_tcp_main ();
3998 if ((error = vlib_call_init_function (vm, tcp_init)))
4001 /* Initialize dispatch table. */
4002 tcp_dispatch_table_init (tm);
4007 VLIB_INIT_FUNCTION (tcp_input_init);
4009 #endif /* CLIB_MARCH_VARIANT */
4012 * fd.io coding-style-patch-verification: ON
4015 * eval: (c-set-style "gnu")