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 * Dequeue bytes for connections that have received acks in last burst
582 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
584 u32 thread_index = wrk->vm->thread_index;
585 u32 *pending_deq_acked;
586 tcp_connection_t *tc;
589 if (!vec_len (wrk->pending_deq_acked))
592 pending_deq_acked = wrk->pending_deq_acked;
593 for (i = 0; i < vec_len (pending_deq_acked); i++)
595 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
596 tc->flags &= ~TCP_CONN_DEQ_PENDING;
598 if (PREDICT_FALSE (!tc->burst_acked))
601 /* Dequeue the newly ACKed bytes */
602 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
603 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
605 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
607 if (seq_leq (tc->psh_seq, tc->snd_una))
608 tc->flags &= ~TCP_CONN_PSH_PENDING;
611 /* If everything has been acked, stop retransmit timer
612 * otherwise update. */
613 tcp_retransmit_timer_update (tc);
615 /* Update pacer based on our new cwnd estimate */
616 tcp_connection_tx_pacer_update (tc);
620 _vec_len (wrk->pending_deq_acked) = 0;
624 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
626 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
628 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
629 tc->flags |= TCP_CONN_DEQ_PENDING;
631 tc->burst_acked += tc->bytes_acked;
634 #ifndef CLIB_MARCH_VARIANT
636 scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
638 ASSERT (!pool_is_free_index (sb->holes, hole - sb->holes));
639 return hole - sb->holes;
643 scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
645 return hole->end - hole->start;
648 sack_scoreboard_hole_t *
649 scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
651 if (index != TCP_INVALID_SACK_HOLE_INDEX)
652 return pool_elt_at_index (sb->holes, index);
656 sack_scoreboard_hole_t *
657 scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
659 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
660 return pool_elt_at_index (sb->holes, hole->next);
664 sack_scoreboard_hole_t *
665 scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
667 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
668 return pool_elt_at_index (sb->holes, hole->prev);
672 sack_scoreboard_hole_t *
673 scoreboard_first_hole (sack_scoreboard_t * sb)
675 if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
676 return pool_elt_at_index (sb->holes, sb->head);
680 sack_scoreboard_hole_t *
681 scoreboard_last_hole (sack_scoreboard_t * sb)
683 if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
684 return pool_elt_at_index (sb->holes, sb->tail);
689 scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
691 sack_scoreboard_hole_t *next, *prev;
693 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
695 next = pool_elt_at_index (sb->holes, hole->next);
696 next->prev = hole->prev;
700 sb->tail = hole->prev;
703 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
705 prev = pool_elt_at_index (sb->holes, hole->prev);
706 prev->next = hole->next;
710 sb->head = hole->next;
713 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
714 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
716 /* Poison the entry */
718 clib_memset (hole, 0xfe, sizeof (*hole));
720 pool_put (sb->holes, hole);
723 static sack_scoreboard_hole_t *
724 scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
727 sack_scoreboard_hole_t *hole, *next, *prev;
730 pool_get (sb->holes, hole);
731 clib_memset (hole, 0, sizeof (*hole));
735 hole_index = scoreboard_hole_index (sb, hole);
737 prev = scoreboard_get_hole (sb, prev_index);
740 hole->prev = prev_index;
741 hole->next = prev->next;
743 if ((next = scoreboard_next_hole (sb, hole)))
744 next->prev = hole_index;
746 sb->tail = hole_index;
748 prev->next = hole_index;
752 sb->head = hole_index;
753 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
754 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
761 scoreboard_update_sacked_rxt (sack_scoreboard_t * sb, u32 start, u32 end,
764 if (!has_rxt || seq_geq (start, sb->high_rxt))
768 seq_lt (end, sb->high_rxt) ? (end - start) : (sb->high_rxt - start);
772 scoreboard_update_bytes (sack_scoreboard_t * sb, u32 ack, u32 snd_mss)
774 sack_scoreboard_hole_t *left, *right;
775 u32 sacked = 0, blks = 0, old_sacked;
777 old_sacked = sb->sacked_bytes;
779 sb->last_lost_bytes = 0;
781 sb->sacked_bytes = 0;
783 right = scoreboard_last_hole (sb);
786 sb->sacked_bytes = sb->high_sacked - ack;
790 if (seq_gt (sb->high_sacked, right->end))
792 sacked = sb->high_sacked - right->end;
796 while (sacked < (TCP_DUPACK_THRESHOLD - 1) * snd_mss
797 && blks < TCP_DUPACK_THRESHOLD)
800 sb->lost_bytes += scoreboard_hole_bytes (right);
802 left = scoreboard_prev_hole (sb, right);
805 ASSERT (right->start == ack || sb->is_reneging);
806 sacked += right->start - ack;
811 sacked += right->start - left->end;
816 /* right is first lost */
819 sb->lost_bytes += scoreboard_hole_bytes (right);
820 sb->last_lost_bytes += right->is_lost ? 0 : (right->end - right->start);
822 left = scoreboard_prev_hole (sb, right);
825 ASSERT (right->start == ack || sb->is_reneging);
826 sacked += right->start - ack;
829 sacked += right->start - left->end;
833 sb->sacked_bytes = sacked;
834 sb->last_sacked_bytes = sacked - (old_sacked - sb->last_bytes_delivered);
838 * Figure out the next hole to retransmit
840 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
842 sack_scoreboard_hole_t *
843 scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
844 sack_scoreboard_hole_t * start,
845 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
847 sack_scoreboard_hole_t *hole = 0;
849 hole = start ? start : scoreboard_first_hole (sb);
850 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
851 hole = scoreboard_next_hole (sb, hole);
853 /* Nothing, return */
856 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
860 /* Rule (1): if higher than rxt, less than high_sacked and lost */
861 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
863 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
867 /* Rule (2): available unsent data */
870 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
873 /* Rule (3): if hole not lost */
874 else if (seq_lt (hole->start, sb->high_sacked))
876 /* And we didn't already retransmit it */
877 if (seq_leq (hole->end, sb->high_rxt))
879 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
883 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
885 /* Rule (4): if hole beyond high_sacked */
888 ASSERT (seq_geq (hole->start, sb->high_sacked));
891 /* HighRxt MUST NOT be updated */
896 if (hole && seq_lt (sb->high_rxt, hole->start))
897 sb->high_rxt = hole->start;
903 scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una)
905 sack_scoreboard_hole_t *hole;
906 hole = scoreboard_first_hole (sb);
909 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
910 sb->cur_rxt_hole = sb->head;
912 sb->high_rxt = snd_una;
913 sb->rescue_rxt = snd_una - 1;
917 scoreboard_init (sack_scoreboard_t * sb)
919 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
920 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
921 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
925 scoreboard_clear (sack_scoreboard_t * sb)
927 sack_scoreboard_hole_t *hole;
928 while ((hole = scoreboard_first_hole (sb)))
930 scoreboard_remove_hole (sb, hole);
932 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
933 ASSERT (pool_elts (sb->holes) == 0);
934 sb->sacked_bytes = 0;
935 sb->last_sacked_bytes = 0;
936 sb->last_bytes_delivered = 0;
938 sb->last_lost_bytes = 0;
939 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
944 scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end)
946 sack_scoreboard_hole_t *last_hole;
948 clib_warning ("sack reneging");
950 scoreboard_clear (sb);
951 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
953 last_hole->is_lost = 1;
954 sb->tail = scoreboard_hole_index (sb, last_hole);
955 sb->high_sacked = start;
956 scoreboard_init_rxt (sb, start);
959 #endif /* CLIB_MARCH_VARIANT */
962 * Test that scoreboard is sane after recovery
964 * Returns 1 if scoreboard is empty or if first hole beyond
968 tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
970 sack_scoreboard_hole_t *hole;
971 hole = scoreboard_first_hole (&tc->sack_sb);
972 return (!hole || (seq_geq (hole->start, tc->snd_una)
973 && seq_lt (hole->end, tc->snd_nxt)));
976 #ifndef CLIB_MARCH_VARIANT
979 tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
981 sack_scoreboard_hole_t *hole, *next_hole;
982 sack_scoreboard_t *sb = &tc->sack_sb;
983 sack_block_t *blk, *rcv_sacks;
984 u32 blk_index = 0, i, j;
987 sb->last_sacked_bytes = 0;
988 sb->last_bytes_delivered = 0;
991 if (!tcp_opts_sack (&tc->rcv_opts)
992 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
995 has_rxt = tcp_in_cong_recovery (tc);
997 /* Remove invalid blocks */
998 blk = tc->rcv_opts.sacks;
999 while (blk < vec_end (tc->rcv_opts.sacks))
1001 if (seq_lt (blk->start, blk->end)
1002 && seq_gt (blk->start, tc->snd_una)
1003 && seq_gt (blk->start, ack)
1004 && seq_lt (blk->start, tc->snd_nxt)
1005 && seq_leq (blk->end, tc->snd_nxt))
1010 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
1013 /* Add block for cumulative ack */
1014 if (seq_gt (ack, tc->snd_una))
1016 vec_add2 (tc->rcv_opts.sacks, blk, 1);
1017 blk->start = tc->snd_una;
1021 if (vec_len (tc->rcv_opts.sacks) == 0)
1024 tcp_scoreboard_trace_add (tc, ack);
1026 /* Make sure blocks are ordered */
1027 rcv_sacks = tc->rcv_opts.sacks;
1028 for (i = 0; i < vec_len (rcv_sacks); i++)
1029 for (j = i + 1; j < vec_len (rcv_sacks); j++)
1030 if (seq_lt (rcv_sacks[j].start, rcv_sacks[i].start))
1032 sack_block_t tmp = rcv_sacks[i];
1033 rcv_sacks[i] = rcv_sacks[j];
1037 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1039 /* Handle reneging as a special case */
1040 if (PREDICT_FALSE (sb->is_reneging))
1042 /* No holes, only sacked bytes */
1043 if (seq_leq (tc->snd_nxt, sb->high_sacked))
1045 /* No progress made so return */
1046 if (seq_leq (ack, tc->snd_una))
1049 /* Update sacked bytes delivered and return */
1050 sb->last_bytes_delivered = ack - tc->snd_una;
1051 sb->sacked_bytes -= sb->last_bytes_delivered;
1052 sb->is_reneging = seq_lt (ack, sb->high_sacked);
1056 /* New hole above high sacked. Add it and process normally */
1057 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1058 sb->high_sacked, tc->snd_nxt);
1059 sb->tail = scoreboard_hole_index (sb, hole);
1061 /* Not reneging and no holes. Insert the first that covers all
1062 * outstanding bytes */
1065 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1066 tc->snd_una, tc->snd_nxt);
1067 sb->tail = scoreboard_hole_index (sb, hole);
1069 sb->high_sacked = rcv_sacks[vec_len (rcv_sacks) - 1].end;
1073 /* If we have holes but snd_nxt is beyond the last hole, update
1074 * last hole end or add new hole after high sacked */
1075 hole = scoreboard_last_hole (sb);
1076 if (seq_gt (tc->snd_nxt, hole->end))
1078 if (seq_geq (hole->start, sb->high_sacked))
1080 hole->end = tc->snd_nxt;
1082 /* New hole after high sacked block */
1083 else if (seq_lt (sb->high_sacked, tc->snd_nxt))
1085 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
1090 /* Keep track of max byte sacked for when the last hole
1092 sb->high_sacked = seq_max (rcv_sacks[vec_len (rcv_sacks) - 1].end,
1096 /* Walk the holes with the SACK blocks */
1097 hole = pool_elt_at_index (sb->holes, sb->head);
1099 if (PREDICT_FALSE (sb->is_reneging))
1100 sb->last_bytes_delivered += hole->start - tc->snd_una;
1102 while (hole && blk_index < vec_len (rcv_sacks))
1104 blk = &rcv_sacks[blk_index];
1105 if (seq_leq (blk->start, hole->start))
1107 /* Block covers hole. Remove hole */
1108 if (seq_geq (blk->end, hole->end))
1110 next_hole = scoreboard_next_hole (sb, hole);
1112 /* If covered by ack, compute delivered bytes */
1113 if (blk->end == ack)
1115 u32 sacked = next_hole ? next_hole->start : sb->high_sacked;
1116 if (PREDICT_FALSE (seq_lt (ack, sacked)))
1118 sb->last_bytes_delivered += ack - hole->end;
1119 sb->is_reneging = 1;
1123 sb->last_bytes_delivered += sacked - hole->end;
1124 sb->is_reneging = 0;
1127 scoreboard_update_sacked_rxt (sb, hole->start, hole->end,
1129 scoreboard_remove_hole (sb, hole);
1132 /* Partial 'head' overlap */
1135 if (seq_gt (blk->end, hole->start))
1137 scoreboard_update_sacked_rxt (sb, hole->start, blk->end,
1139 hole->start = blk->end;
1146 /* Hole must be split */
1147 if (seq_lt (blk->end, hole->end))
1149 u32 hole_index = scoreboard_hole_index (sb, hole);
1150 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1152 /* Pool might've moved */
1153 hole = scoreboard_get_hole (sb, hole_index);
1154 hole->end = blk->start;
1156 scoreboard_update_sacked_rxt (sb, blk->start, blk->end,
1160 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
1162 else if (seq_lt (blk->start, hole->end))
1164 scoreboard_update_sacked_rxt (sb, blk->start, hole->end,
1166 hole->end = blk->start;
1168 hole = scoreboard_next_hole (sb, hole);
1172 scoreboard_update_bytes (sb, ack, tc->snd_mss);
1174 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
1175 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
1176 || sb->sacked_bytes <= tc->snd_nxt - seq_max (tc->snd_una, ack));
1177 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_nxt
1178 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
1179 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1180 || sb->is_reneging || sb->holes[sb->head].start == ack);
1181 ASSERT (sb->last_lost_bytes <= sb->lost_bytes);
1182 ASSERT ((ack - tc->snd_una) + sb->last_sacked_bytes
1183 - sb->last_bytes_delivered >= sb->rxt_sacked);
1184 ASSERT ((ack - tc->snd_una) >= tc->sack_sb.last_bytes_delivered
1185 || (tc->flags & TCP_CONN_FINSNT));
1187 TCP_EVT (TCP_EVT_CC_SCOREBOARD, tc);
1189 #endif /* CLIB_MARCH_VARIANT */
1192 * Try to update snd_wnd based on feedback received from peer.
1194 * If successful, and new window is 'effectively' 0, activate persist
1198 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1200 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1201 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
1202 if (seq_lt (tc->snd_wl1, seq)
1203 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
1205 tc->snd_wnd = snd_wnd;
1208 TCP_EVT (TCP_EVT_SND_WND, tc);
1210 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
1212 /* Set persist timer if not set and we just got 0 wnd */
1213 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1214 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
1215 tcp_persist_timer_set (tc);
1219 tcp_persist_timer_reset (tc);
1220 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
1223 tcp_update_rto (tc);
1230 * Init loss recovery/fast recovery.
1232 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1233 * updated in @ref tcp_cc_handle_event after fast retransmit
1236 tcp_cc_init_congestion (tcp_connection_t * tc)
1238 tcp_fastrecovery_on (tc);
1239 tc->snd_congestion = tc->snd_nxt;
1240 tc->cwnd_acc_bytes = 0;
1241 tc->snd_rxt_bytes = 0;
1242 tc->rxt_delivered = 0;
1243 tc->prr_delivered = 0;
1244 tc->prr_start = tc->snd_una;
1245 tc->prev_ssthresh = tc->ssthresh;
1246 tc->prev_cwnd = tc->cwnd;
1248 tc->snd_rxt_ts = tcp_tstamp (tc);
1249 tcp_cc_congestion (tc);
1251 /* Post retransmit update cwnd to ssthresh and account for the
1252 * three segments that have left the network and should've been
1253 * buffered at the receiver XXX */
1254 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
1255 tc->cwnd += 3 * tc->snd_mss;
1257 tc->fr_occurences += 1;
1258 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
1262 tcp_cc_congestion_undo (tcp_connection_t * tc)
1264 tc->cwnd = tc->prev_cwnd;
1265 tc->ssthresh = tc->prev_ssthresh;
1266 tcp_cc_undo_recovery (tc);
1267 ASSERT (tc->rto_boff == 0);
1268 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
1272 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
1274 return (tcp_in_recovery (tc) && tc->rto_boff == 1
1276 && tcp_opts_tstamp (&tc->rcv_opts)
1277 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1281 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1283 return (tcp_cc_is_spurious_timeout_rxt (tc));
1287 tcp_should_fastrecover_sack (tcp_connection_t * tc)
1289 return (tc->sack_sb.lost_bytes
1290 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
1291 < tc->sack_sb.sacked_bytes));
1295 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
1299 /* If of of the two conditions lower hold, reset dupacks because
1300 * we're probably after timeout (RFC6582 heuristics).
1301 * If Cumulative ack does not cover more than congestion threshold,
1303 * 1) The following doesn't hold: The congestion window is greater
1304 * than SMSS bytes and the difference between highest_ack
1305 * and prev_highest_ack is at most 4*SMSS bytes
1306 * 2) Echoed timestamp in the last non-dup ack does not equal the
1309 if (seq_leq (tc->snd_una, tc->snd_congestion)
1310 && ((!(tc->cwnd > tc->snd_mss
1311 && tc->bytes_acked <= 4 * tc->snd_mss))
1312 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1314 tc->rcv_dupacks = 0;
1318 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1319 || tcp_should_fastrecover_sack (tc));
1323 tcp_cc_recover (tcp_connection_t * tc)
1325 sack_scoreboard_hole_t *hole;
1328 ASSERT (tcp_in_cong_recovery (tc));
1330 if (tcp_cc_is_spurious_retransmit (tc))
1332 tcp_cc_congestion_undo (tc);
1336 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1337 tc->rcv_dupacks = 0;
1339 /* Previous recovery left us congested. Continue sending as part
1340 * of the current recovery event with an updated snd_congestion */
1341 if (tc->sack_sb.sacked_bytes)
1343 tc->snd_congestion = tc->snd_nxt;
1344 tcp_program_retransmit (tc);
1348 tc->rxt_delivered = 0;
1349 tc->snd_rxt_bytes = 0;
1351 tc->prr_delivered = 0;
1353 tc->flags &= ~TCP_CONN_RXT_PENDING;
1355 hole = scoreboard_first_hole (&tc->sack_sb);
1356 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
1357 scoreboard_clear (&tc->sack_sb);
1359 if (!tcp_in_recovery (tc) && !is_spurious)
1360 tcp_cc_recovered (tc);
1362 tcp_fastrecovery_off (tc);
1363 tcp_fastrecovery_first_off (tc);
1364 tcp_recovery_off (tc);
1365 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1367 ASSERT (tc->rto_boff == 0);
1368 ASSERT (!tcp_in_cong_recovery (tc));
1369 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
1374 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1376 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
1378 /* Congestion avoidance */
1379 tcp_cc_rcv_ack (tc, rs);
1381 /* If a cumulative ack, make sure dupacks is 0 */
1382 tc->rcv_dupacks = 0;
1384 /* When dupacks hits the threshold we only enter fast retransmit if
1385 * cumulative ack covers more than snd_congestion. Should snd_una
1386 * wrap this test may fail under otherwise valid circumstances.
1387 * Therefore, proactively update snd_congestion when wrap detected. */
1389 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1390 && seq_gt (tc->snd_congestion, tc->snd_una)))
1391 tc->snd_congestion = tc->snd_una - 1;
1395 * One function to rule them all ... and in the darkness bind them
1398 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
1401 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
1403 /* If reneging, wait for timer based retransmits */
1404 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
1408 * If not in recovery, figure out if we should enter
1410 if (!tcp_in_cong_recovery (tc))
1415 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1416 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1418 if (tcp_should_fastrecover (tc, has_sack))
1420 tcp_cc_init_congestion (tc);
1423 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1425 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1426 tcp_program_retransmit (tc);
1433 * Already in recovery
1437 * Process (re)transmit feedback. Output path uses this to decide how much
1438 * more data to release into the network
1442 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
1443 tcp_fastrecovery_first_on (tc);
1445 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
1446 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
1447 - tc->sack_sb.last_bytes_delivered;
1449 tcp_program_retransmit (tc);
1455 tc->rcv_dupacks += 1;
1456 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1458 tc->rxt_delivered = clib_max (tc->rxt_delivered + tc->bytes_acked,
1461 tc->prr_delivered += clib_min (tc->snd_mss,
1462 tc->snd_nxt - tc->snd_una);
1464 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
1468 /* If partial ack, assume that the first un-acked segment was lost */
1469 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1470 tcp_fastrecovery_first_on (tc);
1472 tcp_program_retransmit (tc);
1476 * See if we can exit and stop retransmitting
1478 if (seq_geq (tc->snd_una, tc->snd_congestion))
1480 /* If spurious return, we've already updated everything */
1481 if (tcp_cc_recover (tc))
1483 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1487 /* Treat as congestion avoidance ack */
1488 tcp_cc_rcv_ack (tc, rs);
1493 * Notify cc of the event
1496 if (!tc->bytes_acked)
1498 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1502 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1503 * reset dupacks to 0. Also needed if in congestion recovery */
1504 tc->rcv_dupacks = 0;
1506 if (tcp_in_recovery (tc))
1507 tcp_cc_rcv_ack (tc, rs);
1509 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
1513 tcp_handle_old_ack (tcp_connection_t * tc, vlib_buffer_t * b,
1514 tcp_rate_sample_t * rs)
1516 if (!tcp_in_cong_recovery (tc))
1519 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1520 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1522 tc->bytes_acked = 0;
1524 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1525 tcp_bt_sample_delivery_rate (tc, rs);
1527 tcp_cc_handle_event (tc, rs, 1);
1531 * Check if duplicate ack as per RFC5681 Sec. 2
1534 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
1537 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
1538 && seq_gt (tc->snd_nxt, tc->snd_una)
1539 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
1540 && (prev_snd_wnd == tc->snd_wnd));
1544 * Checks if ack is a congestion control event.
1547 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
1548 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
1550 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
1551 * defined to be 'duplicate' as well */
1552 *is_dack = tc->sack_sb.last_sacked_bytes
1553 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
1555 return (*is_dack || tcp_in_cong_recovery (tc));
1559 * Process incoming ACK
1562 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1563 tcp_header_t * th, u32 * error)
1565 u32 prev_snd_wnd, prev_snd_una;
1566 tcp_rate_sample_t rs = { 0 };
1569 TCP_EVT (TCP_EVT_CC_STAT, tc);
1571 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1572 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1574 /* We've probably entered recovery and the peer still has some
1575 * of the data we've sent. Update snd_nxt and accept the ack */
1576 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1577 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1579 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1583 tc->errors.above_ack_wnd += 1;
1584 *error = TCP_ERROR_ACK_FUTURE;
1585 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1589 /* If old ACK, probably it's an old dupack */
1590 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1592 tc->errors.below_ack_wnd += 1;
1593 *error = TCP_ERROR_ACK_OLD;
1594 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1596 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1599 tcp_handle_old_ack (tc, b, &rs);
1601 /* Don't drop yet */
1608 * Looks okay, process feedback
1611 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1612 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1614 prev_snd_wnd = tc->snd_wnd;
1615 prev_snd_una = tc->snd_una;
1616 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1617 vnet_buffer (b)->tcp.ack_number,
1618 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1619 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1620 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1621 tcp_validate_txf_size (tc, tc->bytes_acked);
1623 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1624 tcp_bt_sample_delivery_rate (tc, &rs);
1626 if (tc->bytes_acked)
1628 tcp_program_dequeue (wrk, tc);
1629 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1632 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1635 * Check if we have congestion event
1638 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1640 tcp_cc_handle_event (tc, &rs, is_dack);
1641 tc->dupacks_in += is_dack;
1642 if (!tcp_in_cong_recovery (tc))
1644 *error = TCP_ERROR_ACK_OK;
1647 *error = TCP_ERROR_ACK_DUP;
1648 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1654 * Update congestion control (slow start/congestion avoidance)
1656 tcp_cc_update (tc, &rs);
1657 *error = TCP_ERROR_ACK_OK;
1662 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1664 if (!tcp_disconnect_pending (tc))
1666 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1667 tcp_disconnect_pending_on (tc);
1672 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1674 u32 thread_index, *pending_disconnects;
1675 tcp_connection_t *tc;
1678 if (!vec_len (wrk->pending_disconnects))
1681 thread_index = wrk->vm->thread_index;
1682 pending_disconnects = wrk->pending_disconnects;
1683 for (i = 0; i < vec_len (pending_disconnects); i++)
1685 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1686 tcp_disconnect_pending_off (tc);
1687 session_transport_closing_notify (&tc->connection);
1689 _vec_len (wrk->pending_disconnects) = 0;
1693 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1696 /* Reject out-of-order fins */
1697 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1700 /* Account for the FIN and send ack */
1702 tc->flags |= TCP_CONN_FINRCVD;
1703 tcp_program_ack (tc);
1704 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1705 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1706 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1707 tcp_program_disconnect (wrk, tc);
1708 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1709 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1710 *error = TCP_ERROR_FIN_RCVD;
1713 #ifndef CLIB_MARCH_VARIANT
1715 tcp_sack_vector_is_sane (sack_block_t * sacks)
1718 for (i = 1; i < vec_len (sacks); i++)
1720 if (sacks[i - 1].end == sacks[i].start)
1727 * Build SACK list as per RFC2018.
1729 * Makes sure the first block contains the segment that generated the current
1730 * ACK and the following ones are the ones most recently reported in SACK
1733 * @param tc TCP connection for which the SACK list is updated
1734 * @param start Start sequence number of the newest SACK block
1735 * @param end End sequence of the newest SACK block
1738 tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1740 sack_block_t *new_list = tc->snd_sacks_fl, *block = 0;
1743 /* If the first segment is ooo add it to the list. Last write might've moved
1744 * rcv_nxt over the first segment. */
1745 if (seq_lt (tc->rcv_nxt, start))
1747 vec_add2 (new_list, block, 1);
1748 block->start = start;
1752 /* Find the blocks still worth keeping. */
1753 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1755 /* Discard if rcv_nxt advanced beyond current block */
1756 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
1759 /* Merge or drop if segment overlapped by the new segment */
1760 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1761 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1763 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1764 new_list[0].start = tc->snd_sacks[i].start;
1765 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1766 new_list[0].end = tc->snd_sacks[i].end;
1770 /* Save to new SACK list if we have space. */
1771 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1772 vec_add1 (new_list, tc->snd_sacks[i]);
1775 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
1777 /* Replace old vector with new one */
1778 vec_reset_length (tc->snd_sacks);
1779 tc->snd_sacks_fl = tc->snd_sacks;
1780 tc->snd_sacks = new_list;
1782 /* Segments should not 'touch' */
1783 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
1787 tcp_sack_list_bytes (tcp_connection_t * tc)
1790 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1791 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1794 #endif /* CLIB_MARCH_VARIANT */
1796 /** Enqueue data for delivery to application */
1798 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1801 int written, error = TCP_ERROR_ENQUEUED;
1803 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1805 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1806 1 /* queue event */ , 1);
1807 tc->bytes_in += written;
1809 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1811 /* Update rcv_nxt */
1812 if (PREDICT_TRUE (written == data_len))
1814 tc->rcv_nxt += written;
1816 /* If more data written than expected, account for out-of-order bytes. */
1817 else if (written > data_len)
1819 tc->rcv_nxt += written;
1820 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1822 else if (written > 0)
1824 /* We've written something but FIFO is probably full now */
1825 tc->rcv_nxt += written;
1826 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1830 return TCP_ERROR_FIFO_FULL;
1833 /* Update SACK list if need be */
1834 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1836 /* Remove SACK blocks that have been delivered */
1837 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1843 /** Enqueue out-of-order data */
1845 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1851 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1854 /* Enqueue out-of-order data with relative offset */
1855 rv = session_enqueue_stream_connection (&tc->connection, b,
1856 vnet_buffer (b)->tcp.seq_number -
1857 tc->rcv_nxt, 0 /* queue event */ ,
1860 /* Nothing written */
1863 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1864 return TCP_ERROR_FIFO_FULL;
1867 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1868 tc->bytes_in += data_len;
1870 /* Update SACK list if in use */
1871 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1873 ooo_segment_t *newest;
1876 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1878 /* Get the newest segment from the fifo */
1879 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1882 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1883 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1884 start = tc->rcv_nxt + offset;
1885 end = start + ooo_segment_length (s0->rx_fifo, newest);
1886 tcp_update_sack_list (tc, start, end);
1887 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1888 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1892 return TCP_ERROR_ENQUEUED_OOO;
1896 * Check if ACK could be delayed. If ack can be delayed, it should return
1897 * true for a full frame. If we're always acking return 0.
1900 tcp_can_delack (tcp_connection_t * tc)
1902 /* Send ack if ... */
1904 /* just sent a rcv wnd 0
1905 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1906 /* constrained to send ack */
1907 || (tc->flags & TCP_CONN_SNDACK) != 0
1908 /* we're almost out of tx wnd */
1909 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1916 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1918 u32 discard, first = b->current_length;
1919 vlib_main_t *vm = vlib_get_main ();
1921 /* Handle multi-buffer segments */
1922 if (n_bytes_to_drop > b->current_length)
1924 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1928 discard = clib_min (n_bytes_to_drop, b->current_length);
1929 vlib_buffer_advance (b, discard);
1930 b = vlib_get_buffer (vm, b->next_buffer);
1931 n_bytes_to_drop -= discard;
1933 while (n_bytes_to_drop);
1934 if (n_bytes_to_drop > first)
1935 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1938 vlib_buffer_advance (b, n_bytes_to_drop);
1939 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1944 * Receive buffer for connection and handle acks
1946 * It handles both in order or out-of-order data.
1949 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1952 u32 error, n_bytes_to_drop, n_data_bytes;
1954 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1955 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1956 ASSERT (n_data_bytes);
1957 tc->data_segs_in += 1;
1959 /* Handle out-of-order data */
1960 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1962 /* Old sequence numbers allowed through because they overlapped
1964 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1966 /* Completely in the past (possible retransmit). Ack
1967 * retransmissions since we may not have any data to send */
1968 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1970 tcp_program_ack (tc);
1971 error = TCP_ERROR_SEGMENT_OLD;
1975 /* Chop off the bytes in the past and see if what is left
1976 * can be enqueued in order */
1977 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1978 n_data_bytes -= n_bytes_to_drop;
1979 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1980 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1982 error = TCP_ERROR_SEGMENT_OLD;
1988 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1989 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1990 tcp_program_dupack (tc);
1991 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1992 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1993 tc->rcv_las + tc->rcv_wnd);
1999 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
2000 * segments can be enqueued after fifo tail offset changes. */
2001 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
2002 if (tcp_can_delack (tc))
2004 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
2005 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
2009 tcp_program_ack (tc);
2017 tcp_header_t tcp_header;
2018 tcp_connection_t tcp_connection;
2022 format_tcp_rx_trace (u8 * s, va_list * args)
2024 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2025 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2026 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2027 u32 indent = format_get_indent (s);
2029 s = format (s, "%U\n%U%U",
2030 format_tcp_header, &t->tcp_header, 128,
2031 format_white_space, indent,
2032 format_tcp_connection, &t->tcp_connection, 1);
2038 format_tcp_rx_trace_short (u8 * s, va_list * args)
2040 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2041 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2042 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2044 s = format (s, "%d -> %d (%U)",
2045 clib_net_to_host_u16 (t->tcp_header.dst_port),
2046 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
2047 t->tcp_connection.state);
2053 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
2054 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
2058 clib_memcpy_fast (&t0->tcp_connection, tc0,
2059 sizeof (t0->tcp_connection));
2063 th0 = tcp_buffer_hdr (b0);
2065 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2069 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2070 vlib_frame_t * frame, u8 is_ip4)
2074 n_left = frame->n_vectors;
2075 from = vlib_frame_vector_args (frame);
2079 tcp_connection_t *tc0;
2086 b0 = vlib_get_buffer (vm, bi0);
2088 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2090 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2091 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2093 th0 = tcp_buffer_hdr (b0);
2094 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2103 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2104 u8 is_ip4, u32 evt, u32 val)
2107 vlib_node_increment_counter (vm, tcp4_node, evt, val);
2109 vlib_node_increment_counter (vm, tcp6_node, evt, val);
2112 #define tcp_maybe_inc_counter(node_id, err, count) \
2114 if (next0 != tcp_next_drop (is_ip4)) \
2115 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2116 tcp6_##node_id##_node.index, is_ip4, err, \
2119 #define tcp_inc_counter(node_id, err, count) \
2120 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2121 tcp6_##node_id##_node.index, is_ip4, \
2123 #define tcp_maybe_inc_err_counter(cnts, err) \
2125 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2127 #define tcp_inc_err_counter(cnts, err, val) \
2131 #define tcp_store_err_counters(node_id, cnts) \
2134 for (i = 0; i < TCP_N_ERROR; i++) \
2136 tcp_inc_counter(node_id, i, cnts[i]); \
2141 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2142 vlib_frame_t * frame, int is_ip4)
2144 u32 thread_index = vm->thread_index, errors = 0;
2145 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2146 u32 n_left_from, *from, *first_buffer;
2147 u16 err_counters[TCP_N_ERROR] = { 0 };
2149 if (node->flags & VLIB_NODE_FLAG_TRACE)
2150 tcp_established_trace_frame (vm, node, frame, is_ip4);
2152 first_buffer = from = vlib_frame_vector_args (frame);
2153 n_left_from = frame->n_vectors;
2155 while (n_left_from > 0)
2157 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2160 tcp_connection_t *tc0;
2162 if (n_left_from > 1)
2165 pb = vlib_get_buffer (vm, from[1]);
2166 vlib_prefetch_buffer_header (pb, LOAD);
2167 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2174 b0 = vlib_get_buffer (vm, bi0);
2175 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2178 if (PREDICT_FALSE (tc0 == 0))
2180 error0 = TCP_ERROR_INVALID_CONNECTION;
2184 th0 = tcp_buffer_hdr (b0);
2186 /* TODO header prediction fast path */
2188 /* 1-4: check SEQ, RST, SYN */
2189 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2191 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2195 /* 5: check the ACK field */
2196 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2199 /* 6: check the URG bit TODO */
2201 /* 7: process the segment text */
2202 if (vnet_buffer (b0)->tcp.data_len)
2203 error0 = tcp_segment_rcv (wrk, tc0, b0);
2205 /* 8: check the FIN bit */
2206 if (PREDICT_FALSE (tcp_is_fin (th0)))
2207 tcp_rcv_fin (wrk, tc0, b0, &error0);
2210 tcp_inc_err_counter (err_counters, error0, 1);
2213 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2215 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
2216 tcp_store_err_counters (established, err_counters);
2217 tcp_handle_postponed_dequeues (wrk);
2218 tcp_handle_disconnects (wrk);
2219 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
2221 return frame->n_vectors;
2224 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
2225 vlib_node_runtime_t * node,
2226 vlib_frame_t * from_frame)
2228 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2231 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
2232 vlib_node_runtime_t * node,
2233 vlib_frame_t * from_frame)
2235 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2239 VLIB_REGISTER_NODE (tcp4_established_node) =
2241 .name = "tcp4-established",
2242 /* Takes a vector of packets. */
2243 .vector_size = sizeof (u32),
2244 .n_errors = TCP_N_ERROR,
2245 .error_strings = tcp_error_strings,
2246 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2249 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2250 foreach_tcp_state_next
2253 .format_trace = format_tcp_rx_trace_short,
2258 VLIB_REGISTER_NODE (tcp6_established_node) =
2260 .name = "tcp6-established",
2261 /* Takes a vector of packets. */
2262 .vector_size = sizeof (u32),
2263 .n_errors = TCP_N_ERROR,
2264 .error_strings = tcp_error_strings,
2265 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2268 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2269 foreach_tcp_state_next
2272 .format_trace = format_tcp_rx_trace_short,
2278 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
2281 transport_connection_t *tmp = 0;
2288 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2291 u8 is_ip_valid = 0, val_l, val_r;
2293 if (tc->connection.is_ip4)
2295 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
2297 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
2298 &tc->connection.lcl_ip.ip4);
2299 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
2300 val_r = !ip4_address_compare (&ip4_hdr->src_address,
2301 &tc->connection.rmt_ip.ip4);
2302 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2303 is_ip_valid = val_l && val_r;
2307 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
2309 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
2310 &tc->connection.lcl_ip.ip6);
2311 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
2312 val_r = !ip6_address_compare (&ip6_hdr->src_address,
2313 &tc->connection.rmt_ip.ip6);
2314 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2315 is_ip_valid = val_l && val_r;
2318 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2319 && (tc->state == TCP_STATE_LISTEN
2320 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
2324 handle = session_lookup_half_open_handle (&tc->connection);
2325 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
2326 tc->c_proto, tc->c_is_ip4);
2330 if (tmp->lcl_port == hdr->dst_port
2331 && tmp->rmt_port == hdr->src_port)
2333 TCP_DBG ("half-open is valid!");
2342 * Lookup transport connection
2344 static tcp_connection_t *
2345 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2349 transport_connection_t *tconn;
2350 tcp_connection_t *tc;
2355 ip4 = vlib_buffer_get_current (b);
2356 tcp = ip4_next_header (ip4);
2357 tconn = session_lookup_connection_wt4 (fib_index,
2362 TRANSPORT_PROTO_TCP,
2363 thread_index, &is_filtered);
2364 tc = tcp_get_connection_from_transport (tconn);
2365 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2370 ip6 = vlib_buffer_get_current (b);
2371 tcp = ip6_next_header (ip6);
2372 tconn = session_lookup_connection_wt6 (fib_index,
2377 TRANSPORT_PROTO_TCP,
2378 thread_index, &is_filtered);
2379 tc = tcp_get_connection_from_transport (tconn);
2380 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2385 static tcp_connection_t *
2386 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
2392 ip4_header_t *ip4 = vlib_buffer_get_current (b);
2393 tcp_header_t *tcp = tcp_buffer_hdr (b);
2394 s = session_lookup_listener4 (fib_index,
2396 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
2400 ip6_header_t *ip6 = vlib_buffer_get_current (b);
2401 tcp_header_t *tcp = tcp_buffer_hdr (b);
2402 s = session_lookup_listener6 (fib_index,
2404 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
2407 if (PREDICT_TRUE (s != 0))
2408 return tcp_get_connection_from_transport (transport_get_listener
2409 (TRANSPORT_PROTO_TCP,
2410 s->connection_index));
2416 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
2418 vnet_main_t *vnm = vnet_get_main ();
2419 const dpo_id_t *dpo;
2420 const load_balance_t *lb;
2421 vnet_hw_interface_t *hw_if;
2422 u32 sw_if_idx, lb_idx;
2426 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
2427 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
2431 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
2432 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
2435 lb = load_balance_get (lb_idx);
2436 dpo = load_balance_get_bucket_i (lb, 0);
2438 sw_if_idx = dpo->dpoi_index;
2439 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
2441 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
2442 tc->cfg_flags |= TCP_CFG_F_TSO;
2446 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2447 vlib_frame_t * from_frame, int is_ip4)
2449 u32 n_left_from, *from, *first_buffer, errors = 0;
2450 u32 my_thread_index = vm->thread_index;
2451 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2453 from = first_buffer = vlib_frame_vector_args (from_frame);
2454 n_left_from = from_frame->n_vectors;
2456 while (n_left_from > 0)
2458 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2459 tcp_connection_t *tc0, *new_tc0;
2460 tcp_header_t *tcp0 = 0;
2468 b0 = vlib_get_buffer (vm, bi0);
2470 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2471 if (PREDICT_FALSE (tc0 == 0))
2473 error0 = TCP_ERROR_INVALID_CONNECTION;
2477 /* Half-open completed recently but the connection was't removed
2478 * yet by the owning thread */
2479 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2481 /* Make sure the connection actually exists */
2482 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2483 my_thread_index, is_ip4));
2484 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2488 ack0 = vnet_buffer (b0)->tcp.ack_number;
2489 seq0 = vnet_buffer (b0)->tcp.seq_number;
2490 tcp0 = tcp_buffer_hdr (b0);
2492 /* Crude check to see if the connection handle does not match
2493 * the packet. Probably connection just switched to established */
2494 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2495 || tcp0->src_port != tc0->c_rmt_port))
2497 error0 = TCP_ERROR_INVALID_CONNECTION;
2501 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2502 && !tcp_syn (tcp0)))
2504 error0 = TCP_ERROR_SEGMENT_INVALID;
2508 /* SYNs consume sequence numbers */
2509 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2512 * 1. check the ACK bit
2516 * If the ACK bit is set
2517 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2518 * the RST bit is set, if so drop the segment and return)
2519 * <SEQ=SEG.ACK><CTL=RST>
2520 * and discard the segment. Return.
2521 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2525 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2527 if (!tcp_rst (tcp0))
2528 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2529 error0 = TCP_ERROR_RCV_WND;
2533 /* Make sure ACK is valid */
2534 if (seq_gt (tc0->snd_una, ack0))
2536 error0 = TCP_ERROR_ACK_INVALID;
2542 * 2. check the RST bit
2547 /* If ACK is acceptable, signal client that peer is not
2548 * willing to accept connection and drop connection*/
2550 tcp_connection_reset (tc0);
2551 error0 = TCP_ERROR_RST_RCVD;
2556 * 3. check the security and precedence (skipped)
2560 * 4. check the SYN bit
2563 /* No SYN flag. Drop. */
2564 if (!tcp_syn (tcp0))
2566 error0 = TCP_ERROR_SEGMENT_INVALID;
2571 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2573 error0 = TCP_ERROR_OPTIONS;
2577 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2578 * current thread pool. */
2579 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2580 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2581 new_tc0->irs = seq0;
2582 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2583 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2585 /* If this is not the owning thread, wait for syn retransmit to
2586 * expire and cleanup then */
2587 if (tcp_half_open_connection_cleanup (tc0))
2588 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2590 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2592 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2593 new_tc0->tsval_recent_age = tcp_time_now ();
2596 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2597 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2599 new_tc0->rcv_wscale = 0;
2601 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2602 << new_tc0->snd_wscale;
2603 new_tc0->snd_wl1 = seq0;
2604 new_tc0->snd_wl2 = ack0;
2606 tcp_connection_init_vars (new_tc0);
2608 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2609 if (PREDICT_TRUE (tcp_ack (tcp0)))
2611 /* Our SYN is ACKed: we have iss < ack = snd_una */
2613 /* TODO Dequeue acknowledged segments if we support Fast Open */
2614 new_tc0->snd_una = ack0;
2615 new_tc0->state = TCP_STATE_ESTABLISHED;
2617 /* Make sure las is initialized for the wnd computation */
2618 new_tc0->rcv_las = new_tc0->rcv_nxt;
2620 /* Notify app that we have connection. If session layer can't
2621 * allocate session send reset */
2622 if (session_stream_connect_notify (&new_tc0->connection, 0))
2624 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2625 tcp_connection_cleanup (new_tc0);
2626 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2630 new_tc0->tx_fifo_size =
2631 transport_tx_fifo_size (&new_tc0->connection);
2632 /* Update rtt with the syn-ack sample */
2633 tcp_estimate_initial_rtt (new_tc0);
2634 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2635 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2637 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2640 new_tc0->state = TCP_STATE_SYN_RCVD;
2642 /* Notify app that we have connection */
2643 if (session_stream_connect_notify (&new_tc0->connection, 0))
2645 tcp_connection_cleanup (new_tc0);
2646 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2647 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2648 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2652 new_tc0->tx_fifo_size =
2653 transport_tx_fifo_size (&new_tc0->connection);
2654 new_tc0->rtt_ts = 0;
2655 tcp_init_snd_vars (new_tc0);
2656 tcp_send_synack (new_tc0);
2657 error0 = TCP_ERROR_SYNS_RCVD;
2661 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2662 tcp_check_tx_offload (new_tc0, is_ip4);
2664 /* Read data, if any */
2665 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2667 clib_warning ("rcvd data in syn-sent");
2668 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2669 if (error0 == TCP_ERROR_ACK_OK)
2670 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2674 /* Send ack now instead of programming it because connection was
2675 * just established and it's not optional. */
2676 tcp_send_ack (new_tc0);
2681 tcp_inc_counter (syn_sent, error0, 1);
2682 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2684 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2685 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2686 clib_memcpy_fast (&t0->tcp_connection, tc0,
2687 sizeof (t0->tcp_connection));
2691 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2693 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2694 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2696 return from_frame->n_vectors;
2699 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2700 vlib_node_runtime_t * node,
2701 vlib_frame_t * from_frame)
2703 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2706 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2707 vlib_node_runtime_t * node,
2708 vlib_frame_t * from_frame)
2710 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2714 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2716 .name = "tcp4-syn-sent",
2717 /* Takes a vector of packets. */
2718 .vector_size = sizeof (u32),
2719 .n_errors = TCP_N_ERROR,
2720 .error_strings = tcp_error_strings,
2721 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2724 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2725 foreach_tcp_state_next
2728 .format_trace = format_tcp_rx_trace_short,
2733 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2735 .name = "tcp6-syn-sent",
2736 /* Takes a vector of packets. */
2737 .vector_size = sizeof (u32),
2738 .n_errors = TCP_N_ERROR,
2739 .error_strings = tcp_error_strings,
2740 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2743 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2744 foreach_tcp_state_next
2747 .format_trace = format_tcp_rx_trace_short,
2752 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2753 * as per RFC793 p. 64
2756 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2757 vlib_frame_t * from_frame, int is_ip4)
2759 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2760 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2761 u32 n_left_from, *from, max_dequeue;
2763 from = first_buffer = vlib_frame_vector_args (from_frame);
2764 n_left_from = from_frame->n_vectors;
2766 while (n_left_from > 0)
2768 u32 bi0, error0 = TCP_ERROR_NONE;
2769 tcp_header_t *tcp0 = 0;
2770 tcp_connection_t *tc0;
2778 b0 = vlib_get_buffer (vm, bi0);
2779 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2781 if (PREDICT_FALSE (tc0 == 0))
2783 error0 = TCP_ERROR_INVALID_CONNECTION;
2787 tcp0 = tcp_buffer_hdr (b0);
2788 is_fin0 = tcp_is_fin (tcp0);
2792 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2794 tcp_connection_t *tmp;
2795 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2797 if (tmp->state != tc0->state)
2799 if (tc0->state != TCP_STATE_CLOSED)
2800 clib_warning ("state changed");
2807 * Special treatment for CLOSED
2809 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2811 error0 = TCP_ERROR_CONNECTION_CLOSED;
2816 * For all other states (except LISTEN)
2819 /* 1-4: check SEQ, RST, SYN */
2820 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2823 /* 5: check the ACK field */
2826 case TCP_STATE_SYN_RCVD:
2828 /* Make sure the segment is exactly right */
2829 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2831 tcp_connection_reset (tc0);
2832 error0 = TCP_ERROR_SEGMENT_INVALID;
2837 * If the segment acknowledgment is not acceptable, form a
2839 * <SEQ=SEG.ACK><CTL=RST>
2842 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2844 tcp_connection_reset (tc0);
2848 /* Update rtt and rto */
2849 tcp_estimate_initial_rtt (tc0);
2850 tcp_connection_tx_pacer_update (tc0);
2852 /* Switch state to ESTABLISHED */
2853 tc0->state = TCP_STATE_ESTABLISHED;
2854 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2856 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2857 tcp_check_tx_offload (tc0, is_ip4);
2859 /* Initialize session variables */
2860 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2861 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2862 << tc0->rcv_opts.wscale;
2863 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2864 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2866 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2867 tcp_retransmit_timer_reset (tc0);
2868 if (session_stream_accept_notify (&tc0->connection))
2870 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2871 tcp_connection_reset (tc0);
2874 error0 = TCP_ERROR_ACK_OK;
2876 case TCP_STATE_ESTABLISHED:
2877 /* We can get packets in established state here because they
2878 * were enqueued before state change */
2879 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2883 case TCP_STATE_FIN_WAIT_1:
2884 /* In addition to the processing for the ESTABLISHED state, if
2885 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2886 * continue processing in that state. */
2887 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2890 /* Still have to send the FIN */
2891 if (tc0->flags & TCP_CONN_FINPNDG)
2893 /* TX fifo finally drained */
2894 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2895 if (max_dequeue <= tc0->burst_acked)
2897 /* If a fin was received and data was acked extend wait */
2898 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2899 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2900 tcp_cfg.closewait_time);
2902 /* If FIN is ACKed */
2903 else if (tc0->snd_una == tc0->snd_nxt)
2905 /* Stop all retransmit timers because we have nothing more
2907 tcp_connection_timers_reset (tc0);
2909 /* We already have a FIN but didn't transition to CLOSING
2910 * because of outstanding tx data. Close the connection. */
2911 if (tc0->flags & TCP_CONN_FINRCVD)
2913 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2914 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE,
2915 tcp_cfg.cleanup_time);
2916 session_transport_closed_notify (&tc0->connection);
2920 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2921 /* Enable waitclose because we're willing to wait for peer's
2922 * FIN but not indefinitely. */
2923 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2925 /* Don't try to deq the FIN acked */
2926 if (tc0->burst_acked > 1)
2927 session_tx_fifo_dequeue_drop (&tc0->connection,
2928 tc0->burst_acked - 1);
2929 tc0->burst_acked = 0;
2932 case TCP_STATE_FIN_WAIT_2:
2933 /* In addition to the processing for the ESTABLISHED state, if
2934 * the retransmission queue is empty, the user's CLOSE can be
2935 * acknowledged ("ok") but do not delete the TCB. */
2936 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2938 tc0->burst_acked = 0;
2940 case TCP_STATE_CLOSE_WAIT:
2941 /* Do the same processing as for the ESTABLISHED state. */
2942 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2945 if (!(tc0->flags & TCP_CONN_FINPNDG))
2948 /* Still have outstanding tx data */
2949 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2950 if (max_dequeue > tc0->burst_acked)
2954 tcp_connection_timers_reset (tc0);
2955 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2956 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2958 case TCP_STATE_CLOSING:
2959 /* In addition to the processing for the ESTABLISHED state, if
2960 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2961 * otherwise ignore the segment. */
2962 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2965 if (tc0->snd_una != tc0->snd_nxt)
2968 tcp_connection_timers_reset (tc0);
2969 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2970 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2971 session_transport_closed_notify (&tc0->connection);
2975 case TCP_STATE_LAST_ACK:
2976 /* The only thing that [should] arrive in this state is an
2977 * acknowledgment of our FIN. If our FIN is now acknowledged,
2978 * delete the TCB, enter the CLOSED state, and return. */
2980 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2983 /* Apparently our ACK for the peer's FIN was lost */
2984 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2990 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2991 session_transport_closed_notify (&tc0->connection);
2993 /* Don't free the connection from the data path since
2994 * we can't ensure that we have no packets already enqueued
2995 * to output. Rely instead on the waitclose timer */
2996 tcp_connection_timers_reset (tc0);
2997 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
3002 case TCP_STATE_TIME_WAIT:
3003 /* The only thing that can arrive in this state is a
3004 * retransmission of the remote FIN. Acknowledge it, and restart
3005 * the 2 MSL timeout. */
3007 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3013 tcp_program_ack (tc0);
3014 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3022 /* 6: check the URG bit TODO */
3024 /* 7: process the segment text */
3027 case TCP_STATE_ESTABLISHED:
3028 case TCP_STATE_FIN_WAIT_1:
3029 case TCP_STATE_FIN_WAIT_2:
3030 if (vnet_buffer (b0)->tcp.data_len)
3031 error0 = tcp_segment_rcv (wrk, tc0, b0);
3033 case TCP_STATE_CLOSE_WAIT:
3034 case TCP_STATE_CLOSING:
3035 case TCP_STATE_LAST_ACK:
3036 case TCP_STATE_TIME_WAIT:
3037 /* This should not occur, since a FIN has been received from the
3038 * remote side. Ignore the segment text. */
3042 /* 8: check the FIN bit */
3046 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
3050 case TCP_STATE_ESTABLISHED:
3051 /* Account for the FIN and send ack */
3053 tcp_program_ack (tc0);
3054 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
3055 tcp_program_disconnect (wrk, tc0);
3056 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
3058 case TCP_STATE_SYN_RCVD:
3059 /* Send FIN-ACK, enter LAST-ACK and because the app was not
3060 * notified yet, set a cleanup timer instead of relying on
3061 * disconnect notify and the implicit close call. */
3062 tcp_connection_timers_reset (tc0);
3065 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3066 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3068 case TCP_STATE_CLOSE_WAIT:
3069 case TCP_STATE_CLOSING:
3070 case TCP_STATE_LAST_ACK:
3073 case TCP_STATE_FIN_WAIT_1:
3076 if (tc0->flags & TCP_CONN_FINPNDG)
3078 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
3079 * sending it. Since we already received a fin, do not wait
3081 tc0->flags |= TCP_CONN_FINRCVD;
3082 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3083 tcp_cfg.closewait_time);
3087 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
3088 tcp_program_ack (tc0);
3089 /* Wait for ACK for our FIN but not forever */
3090 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3091 tcp_cfg.closing_time);
3094 case TCP_STATE_FIN_WAIT_2:
3095 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
3097 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3098 tcp_connection_timers_reset (tc0);
3099 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3100 tcp_program_ack (tc0);
3101 session_transport_closed_notify (&tc0->connection);
3103 case TCP_STATE_TIME_WAIT:
3104 /* Remain in the TIME-WAIT state. Restart the time-wait
3107 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3110 error0 = TCP_ERROR_FIN_RCVD;
3114 tcp_inc_counter (rcv_process, error0, 1);
3115 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3117 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3118 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
3122 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
3124 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
3125 tcp_handle_postponed_dequeues (wrk);
3126 tcp_handle_disconnects (wrk);
3127 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3129 return from_frame->n_vectors;
3132 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
3133 vlib_node_runtime_t * node,
3134 vlib_frame_t * from_frame)
3136 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3139 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
3140 vlib_node_runtime_t * node,
3141 vlib_frame_t * from_frame)
3143 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3147 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
3149 .name = "tcp4-rcv-process",
3150 /* Takes a vector of packets. */
3151 .vector_size = sizeof (u32),
3152 .n_errors = TCP_N_ERROR,
3153 .error_strings = tcp_error_strings,
3154 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3157 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3158 foreach_tcp_state_next
3161 .format_trace = format_tcp_rx_trace_short,
3166 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3168 .name = "tcp6-rcv-process",
3169 /* Takes a vector of packets. */
3170 .vector_size = sizeof (u32),
3171 .n_errors = TCP_N_ERROR,
3172 .error_strings = tcp_error_strings,
3173 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3176 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3177 foreach_tcp_state_next
3180 .format_trace = format_tcp_rx_trace_short,
3185 * LISTEN state processing as per RFC 793 p. 65
3188 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3189 vlib_frame_t * from_frame, int is_ip4)
3191 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3192 u32 my_thread_index = vm->thread_index;
3193 tcp_connection_t *tc0;
3195 from = first_buffer = vlib_frame_vector_args (from_frame);
3196 n_left_from = from_frame->n_vectors;
3198 while (n_left_from > 0)
3203 tcp_header_t *th0 = 0;
3204 tcp_connection_t *lc0;
3207 tcp_connection_t *child0;
3208 u32 error0 = TCP_ERROR_NONE;
3214 b0 = vlib_get_buffer (vm, bi0);
3215 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3216 if (PREDICT_FALSE (lc0 == 0))
3218 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
3220 if (tc0->state != TCP_STATE_TIME_WAIT)
3222 error0 = TCP_ERROR_CREATE_EXISTS;
3225 lc0 = tcp_lookup_listener (b0, tc0->c_fib_index, is_ip4);
3226 /* clean up the old session */
3227 tcp_connection_del (tc0);
3232 ip40 = vlib_buffer_get_current (b0);
3233 th0 = tcp_buffer_hdr (b0);
3237 ip60 = vlib_buffer_get_current (b0);
3238 th0 = tcp_buffer_hdr (b0);
3241 /* Create child session. For syn-flood protection use filter */
3243 /* 1. first check for an RST: handled in dispatch */
3244 /* if (tcp_rst (th0))
3248 /* 2. second check for an ACK: handled in dispatch */
3249 /* if (tcp_ack (th0))
3251 tcp_send_reset (b0, is_ip4);
3256 /* 3. check for a SYN (did that already) */
3258 /* Make sure connection wasn't just created */
3259 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3261 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3263 error0 = TCP_ERROR_CREATE_EXISTS;
3267 /* Create child session and send SYN-ACK */
3268 child0 = tcp_connection_alloc (my_thread_index);
3269 child0->c_lcl_port = th0->dst_port;
3270 child0->c_rmt_port = th0->src_port;
3271 child0->c_is_ip4 = is_ip4;
3272 child0->state = TCP_STATE_SYN_RCVD;
3273 child0->c_fib_index = lc0->c_fib_index;
3274 child0->cc_algo = lc0->cc_algo;
3278 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3279 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3283 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3284 sizeof (ip6_address_t));
3285 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3286 sizeof (ip6_address_t));
3289 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3291 error0 = TCP_ERROR_OPTIONS;
3292 tcp_connection_free (child0);
3296 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3297 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3298 child0->rcv_las = child0->rcv_nxt;
3299 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3301 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3302 * segments are used to initialize PAWS. */
3303 if (tcp_opts_tstamp (&child0->rcv_opts))
3305 child0->tsval_recent = child0->rcv_opts.tsval;
3306 child0->tsval_recent_age = tcp_time_now ();
3309 if (tcp_opts_wscale (&child0->rcv_opts))
3310 child0->snd_wscale = child0->rcv_opts.wscale;
3312 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3313 << child0->snd_wscale;
3314 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3315 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3317 tcp_connection_init_vars (child0);
3318 child0->rto = TCP_RTO_MIN;
3320 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3321 lc0->c_thread_index, 0 /* notify */ ))
3323 tcp_connection_cleanup (child0);
3324 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3328 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3329 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3330 tcp_send_synack (child0);
3334 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3336 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3337 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3338 clib_memcpy_fast (&t0->tcp_connection, lc0,
3339 sizeof (t0->tcp_connection));
3342 n_syns += (error0 == TCP_ERROR_NONE);
3345 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3346 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3348 return from_frame->n_vectors;
3351 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3352 vlib_frame_t * from_frame)
3354 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3357 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3358 vlib_frame_t * from_frame)
3360 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3364 VLIB_REGISTER_NODE (tcp4_listen_node) =
3366 .name = "tcp4-listen",
3367 /* Takes a vector of packets. */
3368 .vector_size = sizeof (u32),
3369 .n_errors = TCP_N_ERROR,
3370 .error_strings = tcp_error_strings,
3371 .n_next_nodes = TCP_LISTEN_N_NEXT,
3374 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3375 foreach_tcp_state_next
3378 .format_trace = format_tcp_rx_trace_short,
3383 VLIB_REGISTER_NODE (tcp6_listen_node) =
3385 .name = "tcp6-listen",
3386 /* Takes a vector of packets. */
3387 .vector_size = sizeof (u32),
3388 .n_errors = TCP_N_ERROR,
3389 .error_strings = tcp_error_strings,
3390 .n_next_nodes = TCP_LISTEN_N_NEXT,
3393 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3394 foreach_tcp_state_next
3397 .format_trace = format_tcp_rx_trace_short,
3401 typedef enum _tcp_input_next
3403 TCP_INPUT_NEXT_DROP,
3404 TCP_INPUT_NEXT_LISTEN,
3405 TCP_INPUT_NEXT_RCV_PROCESS,
3406 TCP_INPUT_NEXT_SYN_SENT,
3407 TCP_INPUT_NEXT_ESTABLISHED,
3408 TCP_INPUT_NEXT_RESET,
3409 TCP_INPUT_NEXT_PUNT,
3413 #define foreach_tcp4_input_next \
3414 _ (DROP, "ip4-drop") \
3415 _ (LISTEN, "tcp4-listen") \
3416 _ (RCV_PROCESS, "tcp4-rcv-process") \
3417 _ (SYN_SENT, "tcp4-syn-sent") \
3418 _ (ESTABLISHED, "tcp4-established") \
3419 _ (RESET, "tcp4-reset") \
3420 _ (PUNT, "ip4-punt")
3422 #define foreach_tcp6_input_next \
3423 _ (DROP, "ip6-drop") \
3424 _ (LISTEN, "tcp6-listen") \
3425 _ (RCV_PROCESS, "tcp6-rcv-process") \
3426 _ (SYN_SENT, "tcp6-syn-sent") \
3427 _ (ESTABLISHED, "tcp6-established") \
3428 _ (RESET, "tcp6-reset") \
3429 _ (PUNT, "ip6-punt")
3431 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3434 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3435 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3437 tcp_connection_t *tc;
3442 for (i = 0; i < n_bufs; i++)
3444 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3446 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3447 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3449 tcp = vlib_buffer_get_current (bs[i]);
3450 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3456 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3458 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3460 *next = TCP_INPUT_NEXT_DROP;
3462 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3464 *next = TCP_INPUT_NEXT_PUNT;
3465 *error = TCP_ERROR_PUNT;
3469 *next = TCP_INPUT_NEXT_RESET;
3470 *error = TCP_ERROR_NO_LISTENER;
3474 always_inline tcp_connection_t *
3475 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3476 u8 is_ip4, u8 is_nolookup)
3478 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3479 int n_advance_bytes, n_data_bytes;
3480 transport_connection_t *tc;
3486 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3487 int ip_hdr_bytes = ip4_header_bytes (ip4);
3488 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3490 *error = TCP_ERROR_LENGTH;
3493 tcp = ip4_next_header (ip4);
3494 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3495 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3496 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3498 /* Length check. Checksum computed by ipx_local no need to compute again */
3499 if (PREDICT_FALSE (n_data_bytes < 0))
3501 *error = TCP_ERROR_LENGTH;
3506 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3507 &ip4->src_address, tcp->dst_port,
3509 TRANSPORT_PROTO_TCP, thread_index,
3514 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3515 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3517 *error = TCP_ERROR_LENGTH;
3520 tcp = ip6_next_header (ip6);
3521 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3522 n_advance_bytes = tcp_header_bytes (tcp);
3523 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3525 n_advance_bytes += sizeof (ip6[0]);
3527 if (PREDICT_FALSE (n_data_bytes < 0))
3529 *error = TCP_ERROR_LENGTH;
3536 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3538 ip4_main_t *im = &ip4_main;
3539 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3540 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3543 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3545 tcp->dst_port, tcp->src_port,
3546 TRANSPORT_PROTO_TCP,
3547 thread_index, &result);
3553 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3554 tcp.connection_index,
3557 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3558 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3559 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3560 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3561 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3563 vnet_buffer (b)->tcp.flags = 0;
3565 *error = result ? TCP_ERROR_NONE + result : *error;
3567 return tcp_get_connection_from_transport (tc);
3571 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3572 vlib_buffer_t * b, u16 * next, u32 * error)
3577 tcp = tcp_buffer_hdr (b);
3578 flags = tcp->flags & filter_flags;
3579 *next = tm->dispatch_table[tc->state][flags].next;
3580 *error = tm->dispatch_table[tc->state][flags].error;
3583 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3584 || *next == TCP_INPUT_NEXT_RESET))
3586 /* Overload tcp flags to store state */
3587 tcp_state_t state = tc->state;
3588 vnet_buffer (b)->tcp.flags = tc->state;
3590 if (*error == TCP_ERROR_DISPATCH)
3591 clib_warning ("tcp conn %u disp error state %U flags %U",
3592 tc->c_c_index, format_tcp_state, state,
3593 format_tcp_flags, (int) flags);
3598 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3599 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3601 u32 n_left_from, *from, thread_index = vm->thread_index;
3602 tcp_main_t *tm = vnet_get_tcp_main ();
3603 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3604 u16 nexts[VLIB_FRAME_SIZE], *next;
3606 tcp_set_time_now (tcp_get_worker (thread_index));
3608 from = vlib_frame_vector_args (frame);
3609 n_left_from = frame->n_vectors;
3610 vlib_get_buffers (vm, from, bufs, n_left_from);
3615 while (n_left_from >= 4)
3617 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3618 tcp_connection_t *tc0, *tc1;
3621 vlib_prefetch_buffer_header (b[2], STORE);
3622 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3624 vlib_prefetch_buffer_header (b[3], STORE);
3625 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3628 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3630 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3632 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3635 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3637 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3638 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3640 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3641 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3643 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3644 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3648 if (PREDICT_TRUE (tc0 != 0))
3650 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3651 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3652 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3655 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3657 if (PREDICT_TRUE (tc1 != 0))
3659 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3660 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3661 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3664 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3671 while (n_left_from > 0)
3673 tcp_connection_t *tc0;
3674 u32 error0 = TCP_ERROR_NO_LISTENER;
3676 if (n_left_from > 1)
3678 vlib_prefetch_buffer_header (b[1], STORE);
3679 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3682 next[0] = TCP_INPUT_NEXT_DROP;
3683 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3685 if (PREDICT_TRUE (tc0 != 0))
3687 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3688 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3689 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3692 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3699 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3700 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3702 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3703 return frame->n_vectors;
3706 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3707 vlib_node_runtime_t * node,
3708 vlib_frame_t * from_frame)
3710 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3711 1 /* is_nolookup */ );
3714 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3715 vlib_node_runtime_t * node,
3716 vlib_frame_t * from_frame)
3718 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3719 1 /* is_nolookup */ );
3723 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3725 .name = "tcp4-input-nolookup",
3726 /* Takes a vector of packets. */
3727 .vector_size = sizeof (u32),
3728 .n_errors = TCP_N_ERROR,
3729 .error_strings = tcp_error_strings,
3730 .n_next_nodes = TCP_INPUT_N_NEXT,
3733 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3734 foreach_tcp4_input_next
3737 .format_buffer = format_tcp_header,
3738 .format_trace = format_tcp_rx_trace,
3743 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3745 .name = "tcp6-input-nolookup",
3746 /* Takes a vector of packets. */
3747 .vector_size = sizeof (u32),
3748 .n_errors = TCP_N_ERROR,
3749 .error_strings = tcp_error_strings,
3750 .n_next_nodes = TCP_INPUT_N_NEXT,
3753 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3754 foreach_tcp6_input_next
3757 .format_buffer = format_tcp_header,
3758 .format_trace = format_tcp_rx_trace,
3762 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3763 vlib_frame_t * from_frame)
3765 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3766 0 /* is_nolookup */ );
3769 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3770 vlib_frame_t * from_frame)
3772 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3773 0 /* is_nolookup */ );
3777 VLIB_REGISTER_NODE (tcp4_input_node) =
3779 .name = "tcp4-input",
3780 /* Takes a vector of packets. */
3781 .vector_size = sizeof (u32),
3782 .n_errors = TCP_N_ERROR,
3783 .error_strings = tcp_error_strings,
3784 .n_next_nodes = TCP_INPUT_N_NEXT,
3787 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3788 foreach_tcp4_input_next
3791 .format_buffer = format_tcp_header,
3792 .format_trace = format_tcp_rx_trace,
3797 VLIB_REGISTER_NODE (tcp6_input_node) =
3799 .name = "tcp6-input",
3800 /* Takes a vector of packets. */
3801 .vector_size = sizeof (u32),
3802 .n_errors = TCP_N_ERROR,
3803 .error_strings = tcp_error_strings,
3804 .n_next_nodes = TCP_INPUT_N_NEXT,
3807 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3808 foreach_tcp6_input_next
3811 .format_buffer = format_tcp_header,
3812 .format_trace = format_tcp_rx_trace,
3816 #ifndef CLIB_MARCH_VARIANT
3818 tcp_dispatch_table_init (tcp_main_t * tm)
3821 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3822 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3824 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3825 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3828 #define _(t,f,n,e) \
3830 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3831 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3834 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3835 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3836 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3837 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3838 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3839 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3840 TCP_ERROR_ACK_INVALID);
3841 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3842 TCP_ERROR_SEGMENT_INVALID);
3843 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3844 TCP_ERROR_SEGMENT_INVALID);
3845 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3846 TCP_ERROR_INVALID_CONNECTION);
3847 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3848 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3849 TCP_ERROR_SEGMENT_INVALID);
3850 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3851 TCP_ERROR_SEGMENT_INVALID);
3852 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3854 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3855 TCP_ERROR_SEGMENT_INVALID);
3856 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3857 TCP_ERROR_SEGMENT_INVALID);
3858 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3859 TCP_ERROR_SEGMENT_INVALID);
3860 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3861 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3862 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3863 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3864 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3865 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3867 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3868 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3870 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3872 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3873 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3874 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3875 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3877 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3879 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3880 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3881 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3883 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3884 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3885 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3886 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3887 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3888 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3889 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3890 /* SYN-ACK for a SYN */
3891 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3893 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3894 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3895 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3897 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3898 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3900 /* ACK for for established connection -> tcp-established. */
3901 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3902 /* FIN for for established connection -> tcp-established. */
3903 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3904 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3906 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3908 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3909 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3910 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3912 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3913 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3914 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3915 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3916 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3917 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3918 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3919 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3921 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3922 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3924 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3926 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3927 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3928 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3929 /* ACK or FIN-ACK to our FIN */
3930 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3931 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3933 /* FIN in reply to our FIN from the other side */
3934 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3935 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3936 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3938 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3939 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3940 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3941 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3942 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3943 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3944 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3946 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3947 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3948 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3949 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3951 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3953 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3954 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3955 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3956 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3958 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3959 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3960 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3961 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3963 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3965 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3966 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3967 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3968 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3970 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3971 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3973 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3975 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3976 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3977 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3979 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3980 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3981 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3982 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3983 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3984 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3985 /* FIN confirming that the peer (app) has closed */
3986 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3987 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3988 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3990 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3991 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3993 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3994 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3996 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3997 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3999 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4000 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4001 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4002 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4004 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4006 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4007 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4008 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4010 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4011 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4012 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4013 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4014 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4015 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4016 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4017 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4019 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4020 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4022 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4024 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4025 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4026 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
4027 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4028 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4030 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4031 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4033 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4034 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
4035 * incoming segment not containing a RST causes a RST to be sent in
4037 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
4038 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
4039 TCP_ERROR_CONNECTION_CLOSED);
4040 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
4041 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
4042 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
4047 static clib_error_t *
4048 tcp_input_init (vlib_main_t * vm)
4050 clib_error_t *error = 0;
4051 tcp_main_t *tm = vnet_get_tcp_main ();
4053 if ((error = vlib_call_init_function (vm, tcp_init)))
4056 /* Initialize dispatch table. */
4057 tcp_dispatch_table_init (tm);
4062 VLIB_INIT_FUNCTION (tcp_input_init);
4064 #endif /* CLIB_MARCH_VARIANT */
4067 * fd.io coding-style-patch-verification: ON
4070 * eval: (c-set-style "gnu")