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;
787 sb->last_sacked_bytes = sb->sacked_bytes
788 - (old_sacked - sb->last_bytes_delivered);
792 if (seq_gt (sb->high_sacked, right->end))
794 sacked = sb->high_sacked - right->end;
798 while (sacked < (TCP_DUPACK_THRESHOLD - 1) * snd_mss
799 && blks < TCP_DUPACK_THRESHOLD)
802 sb->lost_bytes += scoreboard_hole_bytes (right);
804 left = scoreboard_prev_hole (sb, right);
807 ASSERT (right->start == ack || sb->is_reneging);
808 sacked += right->start - ack;
813 sacked += right->start - left->end;
818 /* right is first lost */
821 sb->lost_bytes += scoreboard_hole_bytes (right);
822 sb->last_lost_bytes += right->is_lost ? 0 : (right->end - right->start);
824 left = scoreboard_prev_hole (sb, right);
827 ASSERT (right->start == ack || sb->is_reneging);
828 sacked += right->start - ack;
831 sacked += right->start - left->end;
835 sb->sacked_bytes = sacked;
836 sb->last_sacked_bytes = sacked - (old_sacked - sb->last_bytes_delivered);
840 * Figure out the next hole to retransmit
842 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
844 sack_scoreboard_hole_t *
845 scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
846 sack_scoreboard_hole_t * start,
847 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
849 sack_scoreboard_hole_t *hole = 0;
851 hole = start ? start : scoreboard_first_hole (sb);
852 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
853 hole = scoreboard_next_hole (sb, hole);
855 /* Nothing, return */
858 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
862 /* Rule (1): if higher than rxt, less than high_sacked and lost */
863 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
865 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
869 /* Rule (2): available unsent data */
872 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
875 /* Rule (3): if hole not lost */
876 else if (seq_lt (hole->start, sb->high_sacked))
878 /* And we didn't already retransmit it */
879 if (seq_leq (hole->end, sb->high_rxt))
881 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
885 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
887 /* Rule (4): if hole beyond high_sacked */
890 ASSERT (seq_geq (hole->start, sb->high_sacked));
893 /* HighRxt MUST NOT be updated */
898 if (hole && seq_lt (sb->high_rxt, hole->start))
899 sb->high_rxt = hole->start;
905 scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una)
907 sack_scoreboard_hole_t *hole;
908 hole = scoreboard_first_hole (sb);
911 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
912 sb->cur_rxt_hole = sb->head;
914 sb->high_rxt = snd_una;
915 sb->rescue_rxt = snd_una - 1;
919 scoreboard_init (sack_scoreboard_t * sb)
921 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
922 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
923 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
927 scoreboard_clear (sack_scoreboard_t * sb)
929 sack_scoreboard_hole_t *hole;
930 while ((hole = scoreboard_first_hole (sb)))
932 scoreboard_remove_hole (sb, hole);
934 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
935 ASSERT (pool_elts (sb->holes) == 0);
936 sb->sacked_bytes = 0;
937 sb->last_sacked_bytes = 0;
938 sb->last_bytes_delivered = 0;
940 sb->last_lost_bytes = 0;
941 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
946 scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end)
948 sack_scoreboard_hole_t *last_hole;
950 clib_warning ("sack reneging");
952 scoreboard_clear (sb);
953 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
955 last_hole->is_lost = 1;
956 sb->tail = scoreboard_hole_index (sb, last_hole);
957 sb->high_sacked = start;
958 scoreboard_init_rxt (sb, start);
961 #endif /* CLIB_MARCH_VARIANT */
964 * Test that scoreboard is sane after recovery
966 * Returns 1 if scoreboard is empty or if first hole beyond
970 tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
972 sack_scoreboard_hole_t *hole;
973 hole = scoreboard_first_hole (&tc->sack_sb);
974 return (!hole || (seq_geq (hole->start, tc->snd_una)
975 && seq_lt (hole->end, tc->snd_nxt)));
978 #ifndef CLIB_MARCH_VARIANT
981 tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
983 sack_scoreboard_hole_t *hole, *next_hole;
984 sack_scoreboard_t *sb = &tc->sack_sb;
985 sack_block_t *blk, *rcv_sacks;
986 u32 blk_index = 0, i, j;
989 sb->last_sacked_bytes = 0;
990 sb->last_bytes_delivered = 0;
993 if (!tcp_opts_sack (&tc->rcv_opts)
994 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
997 has_rxt = tcp_in_cong_recovery (tc);
999 /* Remove invalid blocks */
1000 blk = tc->rcv_opts.sacks;
1001 while (blk < vec_end (tc->rcv_opts.sacks))
1003 if (seq_lt (blk->start, blk->end)
1004 && seq_gt (blk->start, tc->snd_una)
1005 && seq_gt (blk->start, ack)
1006 && seq_lt (blk->start, tc->snd_nxt)
1007 && seq_leq (blk->end, tc->snd_nxt))
1012 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
1015 /* Add block for cumulative ack */
1016 if (seq_gt (ack, tc->snd_una))
1018 vec_add2 (tc->rcv_opts.sacks, blk, 1);
1019 blk->start = tc->snd_una;
1023 if (vec_len (tc->rcv_opts.sacks) == 0)
1026 tcp_scoreboard_trace_add (tc, ack);
1028 /* Make sure blocks are ordered */
1029 rcv_sacks = tc->rcv_opts.sacks;
1030 for (i = 0; i < vec_len (rcv_sacks); i++)
1031 for (j = i + 1; j < vec_len (rcv_sacks); j++)
1032 if (seq_lt (rcv_sacks[j].start, rcv_sacks[i].start))
1034 sack_block_t tmp = rcv_sacks[i];
1035 rcv_sacks[i] = rcv_sacks[j];
1039 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1041 /* Handle reneging as a special case */
1042 if (PREDICT_FALSE (sb->is_reneging))
1044 /* No holes, only sacked bytes */
1045 if (seq_leq (tc->snd_nxt, sb->high_sacked))
1047 /* No progress made so return */
1048 if (seq_leq (ack, tc->snd_una))
1051 /* Update sacked bytes delivered and return */
1052 sb->last_bytes_delivered = ack - tc->snd_una;
1053 sb->sacked_bytes -= sb->last_bytes_delivered;
1054 sb->is_reneging = seq_lt (ack, sb->high_sacked);
1058 /* New hole above high sacked. Add it and process normally */
1059 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1060 sb->high_sacked, tc->snd_nxt);
1061 sb->tail = scoreboard_hole_index (sb, hole);
1063 /* Not reneging and no holes. Insert the first that covers all
1064 * outstanding bytes */
1067 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1068 tc->snd_una, tc->snd_nxt);
1069 sb->tail = scoreboard_hole_index (sb, hole);
1071 sb->high_sacked = rcv_sacks[vec_len (rcv_sacks) - 1].end;
1075 /* If we have holes but snd_nxt is beyond the last hole, update
1076 * last hole end or add new hole after high sacked */
1077 hole = scoreboard_last_hole (sb);
1078 if (seq_gt (tc->snd_nxt, hole->end))
1080 if (seq_geq (hole->start, sb->high_sacked))
1082 hole->end = tc->snd_nxt;
1084 /* New hole after high sacked block */
1085 else if (seq_lt (sb->high_sacked, tc->snd_nxt))
1087 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
1092 /* Keep track of max byte sacked for when the last hole
1094 sb->high_sacked = seq_max (rcv_sacks[vec_len (rcv_sacks) - 1].end,
1098 /* Walk the holes with the SACK blocks */
1099 hole = pool_elt_at_index (sb->holes, sb->head);
1101 if (PREDICT_FALSE (sb->is_reneging))
1103 sb->last_bytes_delivered += clib_min (hole->start - tc->snd_una,
1105 sb->is_reneging = seq_lt (ack, hole->start);
1108 while (hole && blk_index < vec_len (rcv_sacks))
1110 blk = &rcv_sacks[blk_index];
1111 if (seq_leq (blk->start, hole->start))
1113 /* Block covers hole. Remove hole */
1114 if (seq_geq (blk->end, hole->end))
1116 next_hole = scoreboard_next_hole (sb, hole);
1118 /* If covered by ack, compute delivered bytes */
1119 if (blk->end == ack)
1121 u32 sacked = next_hole ? next_hole->start : sb->high_sacked;
1122 if (PREDICT_FALSE (seq_lt (ack, sacked)))
1124 sb->last_bytes_delivered += ack - hole->end;
1125 sb->is_reneging = 1;
1129 sb->last_bytes_delivered += sacked - hole->end;
1130 sb->is_reneging = 0;
1133 scoreboard_update_sacked_rxt (sb, hole->start, hole->end,
1135 scoreboard_remove_hole (sb, hole);
1138 /* Partial 'head' overlap */
1141 if (seq_gt (blk->end, hole->start))
1143 scoreboard_update_sacked_rxt (sb, hole->start, blk->end,
1145 hole->start = blk->end;
1152 /* Hole must be split */
1153 if (seq_lt (blk->end, hole->end))
1155 u32 hole_index = scoreboard_hole_index (sb, hole);
1156 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1158 /* Pool might've moved */
1159 hole = scoreboard_get_hole (sb, hole_index);
1160 hole->end = blk->start;
1162 scoreboard_update_sacked_rxt (sb, blk->start, blk->end,
1166 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
1168 else if (seq_lt (blk->start, hole->end))
1170 scoreboard_update_sacked_rxt (sb, blk->start, hole->end,
1172 hole->end = blk->start;
1174 hole = scoreboard_next_hole (sb, hole);
1178 scoreboard_update_bytes (sb, ack, tc->snd_mss);
1180 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
1181 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
1182 || sb->sacked_bytes <= tc->snd_nxt - seq_max (tc->snd_una, ack));
1183 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_nxt
1184 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
1185 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1186 || sb->is_reneging || sb->holes[sb->head].start == ack);
1187 ASSERT (sb->last_lost_bytes <= sb->lost_bytes);
1188 ASSERT ((ack - tc->snd_una) + sb->last_sacked_bytes
1189 - sb->last_bytes_delivered >= sb->rxt_sacked || sb->is_reneging);
1190 ASSERT ((ack - tc->snd_una) >= tc->sack_sb.last_bytes_delivered
1191 || (tc->flags & TCP_CONN_FINSNT));
1193 TCP_EVT (TCP_EVT_CC_SCOREBOARD, tc);
1195 #endif /* CLIB_MARCH_VARIANT */
1198 * Try to update snd_wnd based on feedback received from peer.
1200 * If successful, and new window is 'effectively' 0, activate persist
1204 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1206 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1207 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
1208 if (seq_lt (tc->snd_wl1, seq)
1209 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
1211 tc->snd_wnd = snd_wnd;
1214 TCP_EVT (TCP_EVT_SND_WND, tc);
1216 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
1218 /* Set persist timer if not set and we just got 0 wnd */
1219 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1220 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
1221 tcp_persist_timer_set (tc);
1225 tcp_persist_timer_reset (tc);
1226 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
1229 tcp_update_rto (tc);
1236 * Init loss recovery/fast recovery.
1238 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1239 * updated in @ref tcp_cc_handle_event after fast retransmit
1242 tcp_cc_init_congestion (tcp_connection_t * tc)
1244 tcp_fastrecovery_on (tc);
1245 tc->snd_congestion = tc->snd_nxt;
1246 tc->cwnd_acc_bytes = 0;
1247 tc->snd_rxt_bytes = 0;
1248 tc->rxt_delivered = 0;
1249 tc->prr_delivered = 0;
1250 tc->prr_start = tc->snd_una;
1251 tc->prev_ssthresh = tc->ssthresh;
1252 tc->prev_cwnd = tc->cwnd;
1254 tc->snd_rxt_ts = tcp_tstamp (tc);
1255 tcp_cc_congestion (tc);
1257 /* Post retransmit update cwnd to ssthresh and account for the
1258 * three segments that have left the network and should've been
1259 * buffered at the receiver XXX */
1260 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
1261 tc->cwnd += 3 * tc->snd_mss;
1263 tc->fr_occurences += 1;
1264 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
1268 tcp_cc_congestion_undo (tcp_connection_t * tc)
1270 tc->cwnd = tc->prev_cwnd;
1271 tc->ssthresh = tc->prev_ssthresh;
1272 tcp_cc_undo_recovery (tc);
1273 ASSERT (tc->rto_boff == 0);
1274 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
1278 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
1280 return (tcp_in_recovery (tc) && tc->rto_boff == 1
1282 && tcp_opts_tstamp (&tc->rcv_opts)
1283 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1287 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1289 return (tcp_cc_is_spurious_timeout_rxt (tc));
1293 tcp_should_fastrecover_sack (tcp_connection_t * tc)
1295 return (tc->sack_sb.lost_bytes
1296 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
1297 < tc->sack_sb.sacked_bytes));
1301 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
1305 /* If of of the two conditions lower hold, reset dupacks because
1306 * we're probably after timeout (RFC6582 heuristics).
1307 * If Cumulative ack does not cover more than congestion threshold,
1309 * 1) The following doesn't hold: The congestion window is greater
1310 * than SMSS bytes and the difference between highest_ack
1311 * and prev_highest_ack is at most 4*SMSS bytes
1312 * 2) Echoed timestamp in the last non-dup ack does not equal the
1315 if (seq_leq (tc->snd_una, tc->snd_congestion)
1316 && ((!(tc->cwnd > tc->snd_mss
1317 && tc->bytes_acked <= 4 * tc->snd_mss))
1318 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1320 tc->rcv_dupacks = 0;
1324 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1325 || tcp_should_fastrecover_sack (tc));
1329 tcp_cc_recover (tcp_connection_t * tc)
1331 sack_scoreboard_hole_t *hole;
1334 ASSERT (tcp_in_cong_recovery (tc));
1336 if (tcp_cc_is_spurious_retransmit (tc))
1338 tcp_cc_congestion_undo (tc);
1342 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1343 tc->rcv_dupacks = 0;
1345 /* Previous recovery left us congested. Continue sending as part
1346 * of the current recovery event with an updated snd_congestion */
1347 if (tc->sack_sb.sacked_bytes)
1349 tc->snd_congestion = tc->snd_nxt;
1350 tcp_program_retransmit (tc);
1354 tc->rxt_delivered = 0;
1355 tc->snd_rxt_bytes = 0;
1357 tc->prr_delivered = 0;
1359 tc->flags &= ~TCP_CONN_RXT_PENDING;
1361 hole = scoreboard_first_hole (&tc->sack_sb);
1362 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
1363 scoreboard_clear (&tc->sack_sb);
1365 if (!tcp_in_recovery (tc) && !is_spurious)
1366 tcp_cc_recovered (tc);
1368 tcp_fastrecovery_off (tc);
1369 tcp_fastrecovery_first_off (tc);
1370 tcp_recovery_off (tc);
1371 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1373 ASSERT (tc->rto_boff == 0);
1374 ASSERT (!tcp_in_cong_recovery (tc));
1375 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
1380 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1382 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
1384 /* Congestion avoidance */
1385 tcp_cc_rcv_ack (tc, rs);
1387 /* If a cumulative ack, make sure dupacks is 0 */
1388 tc->rcv_dupacks = 0;
1390 /* When dupacks hits the threshold we only enter fast retransmit if
1391 * cumulative ack covers more than snd_congestion. Should snd_una
1392 * wrap this test may fail under otherwise valid circumstances.
1393 * Therefore, proactively update snd_congestion when wrap detected. */
1395 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1396 && seq_gt (tc->snd_congestion, tc->snd_una)))
1397 tc->snd_congestion = tc->snd_una - 1;
1401 * One function to rule them all ... and in the darkness bind them
1404 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
1407 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
1409 /* If reneging, wait for timer based retransmits */
1410 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
1414 * If not in recovery, figure out if we should enter
1416 if (!tcp_in_cong_recovery (tc))
1421 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1422 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1424 if (tcp_should_fastrecover (tc, has_sack))
1426 tcp_cc_init_congestion (tc);
1429 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1431 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1432 tcp_program_retransmit (tc);
1439 * Already in recovery
1443 * Process (re)transmit feedback. Output path uses this to decide how much
1444 * more data to release into the network
1448 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
1449 tcp_fastrecovery_first_on (tc);
1451 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
1452 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
1453 - tc->sack_sb.last_bytes_delivered;
1455 tcp_program_retransmit (tc);
1461 tc->rcv_dupacks += 1;
1462 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1464 tc->rxt_delivered = clib_max (tc->rxt_delivered + tc->bytes_acked,
1467 tc->prr_delivered += clib_min (tc->snd_mss,
1468 tc->snd_nxt - tc->snd_una);
1470 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
1474 /* If partial ack, assume that the first un-acked segment was lost */
1475 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1476 tcp_fastrecovery_first_on (tc);
1478 tcp_program_retransmit (tc);
1482 * See if we can exit and stop retransmitting
1484 if (seq_geq (tc->snd_una, tc->snd_congestion))
1486 /* If spurious return, we've already updated everything */
1487 if (tcp_cc_recover (tc))
1489 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1493 /* Treat as congestion avoidance ack */
1494 tcp_cc_rcv_ack (tc, rs);
1499 * Notify cc of the event
1502 if (!tc->bytes_acked)
1504 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1508 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1509 * reset dupacks to 0. Also needed if in congestion recovery */
1510 tc->rcv_dupacks = 0;
1512 if (tcp_in_recovery (tc))
1513 tcp_cc_rcv_ack (tc, rs);
1515 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
1519 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1521 if (!tcp_in_cong_recovery (tc))
1524 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1525 tcp_rcv_sacks (tc, tc->snd_una);
1527 tc->bytes_acked = 0;
1529 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1530 tcp_bt_sample_delivery_rate (tc, rs);
1532 tcp_cc_handle_event (tc, rs, 1);
1536 * Check if duplicate ack as per RFC5681 Sec. 2
1539 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
1542 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
1543 && seq_gt (tc->snd_nxt, tc->snd_una)
1544 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
1545 && (prev_snd_wnd == tc->snd_wnd));
1549 * Checks if ack is a congestion control event.
1552 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
1553 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
1555 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
1556 * defined to be 'duplicate' as well */
1557 *is_dack = tc->sack_sb.last_sacked_bytes
1558 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
1560 return (*is_dack || tcp_in_cong_recovery (tc));
1564 * Process incoming ACK
1567 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1568 tcp_header_t * th, u32 * error)
1570 u32 prev_snd_wnd, prev_snd_una;
1571 tcp_rate_sample_t rs = { 0 };
1574 TCP_EVT (TCP_EVT_CC_STAT, tc);
1576 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1577 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1579 /* We've probably entered recovery and the peer still has some
1580 * of the data we've sent. Update snd_nxt and accept the ack */
1581 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1582 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1584 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1588 tc->errors.above_ack_wnd += 1;
1589 *error = TCP_ERROR_ACK_FUTURE;
1590 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1594 /* If old ACK, probably it's an old dupack */
1595 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1597 tc->errors.below_ack_wnd += 1;
1598 *error = TCP_ERROR_ACK_OLD;
1599 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1601 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1604 tcp_handle_old_ack (tc, &rs);
1606 /* Don't drop yet */
1613 * Looks okay, process feedback
1616 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1617 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1619 prev_snd_wnd = tc->snd_wnd;
1620 prev_snd_una = tc->snd_una;
1621 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1622 vnet_buffer (b)->tcp.ack_number,
1623 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1624 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1625 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1626 tcp_validate_txf_size (tc, tc->bytes_acked);
1628 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1629 tcp_bt_sample_delivery_rate (tc, &rs);
1631 if (tc->bytes_acked)
1633 tcp_program_dequeue (wrk, tc);
1634 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1637 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1640 * Check if we have congestion event
1643 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1645 tcp_cc_handle_event (tc, &rs, is_dack);
1646 tc->dupacks_in += is_dack;
1647 if (!tcp_in_cong_recovery (tc))
1649 *error = TCP_ERROR_ACK_OK;
1652 *error = TCP_ERROR_ACK_DUP;
1653 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1659 * Update congestion control (slow start/congestion avoidance)
1661 tcp_cc_update (tc, &rs);
1662 *error = TCP_ERROR_ACK_OK;
1667 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1669 if (!tcp_disconnect_pending (tc))
1671 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1672 tcp_disconnect_pending_on (tc);
1677 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1679 u32 thread_index, *pending_disconnects;
1680 tcp_connection_t *tc;
1683 if (!vec_len (wrk->pending_disconnects))
1686 thread_index = wrk->vm->thread_index;
1687 pending_disconnects = wrk->pending_disconnects;
1688 for (i = 0; i < vec_len (pending_disconnects); i++)
1690 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1691 tcp_disconnect_pending_off (tc);
1692 session_transport_closing_notify (&tc->connection);
1694 _vec_len (wrk->pending_disconnects) = 0;
1698 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1701 /* Reject out-of-order fins */
1702 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1705 /* Account for the FIN and send ack */
1707 tc->flags |= TCP_CONN_FINRCVD;
1708 tcp_program_ack (tc);
1709 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1710 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1711 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1712 tcp_program_disconnect (wrk, tc);
1713 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1714 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1715 *error = TCP_ERROR_FIN_RCVD;
1718 #ifndef CLIB_MARCH_VARIANT
1720 tcp_sack_vector_is_sane (sack_block_t * sacks)
1723 for (i = 1; i < vec_len (sacks); i++)
1725 if (sacks[i - 1].end == sacks[i].start)
1732 * Build SACK list as per RFC2018.
1734 * Makes sure the first block contains the segment that generated the current
1735 * ACK and the following ones are the ones most recently reported in SACK
1738 * @param tc TCP connection for which the SACK list is updated
1739 * @param start Start sequence number of the newest SACK block
1740 * @param end End sequence of the newest SACK block
1743 tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1745 sack_block_t *new_list = tc->snd_sacks_fl, *block = 0;
1748 /* If the first segment is ooo add it to the list. Last write might've moved
1749 * rcv_nxt over the first segment. */
1750 if (seq_lt (tc->rcv_nxt, start))
1752 vec_add2 (new_list, block, 1);
1753 block->start = start;
1757 /* Find the blocks still worth keeping. */
1758 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1760 /* Discard if rcv_nxt advanced beyond current block */
1761 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
1764 /* Merge or drop if segment overlapped by the new segment */
1765 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1766 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1768 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1769 new_list[0].start = tc->snd_sacks[i].start;
1770 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1771 new_list[0].end = tc->snd_sacks[i].end;
1775 /* Save to new SACK list if we have space. */
1776 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1777 vec_add1 (new_list, tc->snd_sacks[i]);
1780 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
1782 /* Replace old vector with new one */
1783 vec_reset_length (tc->snd_sacks);
1784 tc->snd_sacks_fl = tc->snd_sacks;
1785 tc->snd_sacks = new_list;
1787 /* Segments should not 'touch' */
1788 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
1792 tcp_sack_list_bytes (tcp_connection_t * tc)
1795 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1796 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1799 #endif /* CLIB_MARCH_VARIANT */
1801 /** Enqueue data for delivery to application */
1803 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1806 int written, error = TCP_ERROR_ENQUEUED;
1808 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1810 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1811 1 /* queue event */ , 1);
1812 tc->bytes_in += written;
1814 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1816 /* Update rcv_nxt */
1817 if (PREDICT_TRUE (written == data_len))
1819 tc->rcv_nxt += written;
1821 /* If more data written than expected, account for out-of-order bytes. */
1822 else if (written > data_len)
1824 tc->rcv_nxt += written;
1825 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1827 else if (written > 0)
1829 /* We've written something but FIFO is probably full now */
1830 tc->rcv_nxt += written;
1831 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1835 return TCP_ERROR_FIFO_FULL;
1838 /* Update SACK list if need be */
1839 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1841 /* Remove SACK blocks that have been delivered */
1842 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1848 /** Enqueue out-of-order data */
1850 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1856 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1859 /* Enqueue out-of-order data with relative offset */
1860 rv = session_enqueue_stream_connection (&tc->connection, b,
1861 vnet_buffer (b)->tcp.seq_number -
1862 tc->rcv_nxt, 0 /* queue event */ ,
1865 /* Nothing written */
1868 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1869 return TCP_ERROR_FIFO_FULL;
1872 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1873 tc->bytes_in += data_len;
1875 /* Update SACK list if in use */
1876 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1878 ooo_segment_t *newest;
1881 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1883 /* Get the newest segment from the fifo */
1884 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1887 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1888 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1889 start = tc->rcv_nxt + offset;
1890 end = start + ooo_segment_length (s0->rx_fifo, newest);
1891 tcp_update_sack_list (tc, start, end);
1892 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1893 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1897 return TCP_ERROR_ENQUEUED_OOO;
1901 * Check if ACK could be delayed. If ack can be delayed, it should return
1902 * true for a full frame. If we're always acking return 0.
1905 tcp_can_delack (tcp_connection_t * tc)
1907 /* Send ack if ... */
1909 /* just sent a rcv wnd 0
1910 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1911 /* constrained to send ack */
1912 || (tc->flags & TCP_CONN_SNDACK) != 0
1913 /* we're almost out of tx wnd */
1914 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1921 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1923 u32 discard, first = b->current_length;
1924 vlib_main_t *vm = vlib_get_main ();
1926 /* Handle multi-buffer segments */
1927 if (n_bytes_to_drop > b->current_length)
1929 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1933 discard = clib_min (n_bytes_to_drop, b->current_length);
1934 vlib_buffer_advance (b, discard);
1935 b = vlib_get_buffer (vm, b->next_buffer);
1936 n_bytes_to_drop -= discard;
1938 while (n_bytes_to_drop);
1939 if (n_bytes_to_drop > first)
1940 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1943 vlib_buffer_advance (b, n_bytes_to_drop);
1944 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1949 * Receive buffer for connection and handle acks
1951 * It handles both in order or out-of-order data.
1954 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1957 u32 error, n_bytes_to_drop, n_data_bytes;
1959 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1960 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1961 ASSERT (n_data_bytes);
1962 tc->data_segs_in += 1;
1964 /* Handle out-of-order data */
1965 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1967 /* Old sequence numbers allowed through because they overlapped
1969 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1971 /* Completely in the past (possible retransmit). Ack
1972 * retransmissions since we may not have any data to send */
1973 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1975 tcp_program_ack (tc);
1976 error = TCP_ERROR_SEGMENT_OLD;
1980 /* Chop off the bytes in the past and see if what is left
1981 * can be enqueued in order */
1982 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1983 n_data_bytes -= n_bytes_to_drop;
1984 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1985 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1987 error = TCP_ERROR_SEGMENT_OLD;
1993 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1994 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1995 tcp_program_dupack (tc);
1996 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1997 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1998 tc->rcv_las + tc->rcv_wnd);
2004 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
2005 * segments can be enqueued after fifo tail offset changes. */
2006 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
2007 if (tcp_can_delack (tc))
2009 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
2010 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
2014 tcp_program_ack (tc);
2022 tcp_header_t tcp_header;
2023 tcp_connection_t tcp_connection;
2027 format_tcp_rx_trace (u8 * s, va_list * args)
2029 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2030 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2031 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2032 u32 indent = format_get_indent (s);
2034 s = format (s, "%U\n%U%U",
2035 format_tcp_header, &t->tcp_header, 128,
2036 format_white_space, indent,
2037 format_tcp_connection, &t->tcp_connection, 1);
2043 format_tcp_rx_trace_short (u8 * s, va_list * args)
2045 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2046 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2047 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2049 s = format (s, "%d -> %d (%U)",
2050 clib_net_to_host_u16 (t->tcp_header.dst_port),
2051 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
2052 t->tcp_connection.state);
2058 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
2059 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
2063 clib_memcpy_fast (&t0->tcp_connection, tc0,
2064 sizeof (t0->tcp_connection));
2068 th0 = tcp_buffer_hdr (b0);
2070 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2074 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2075 vlib_frame_t * frame, u8 is_ip4)
2079 n_left = frame->n_vectors;
2080 from = vlib_frame_vector_args (frame);
2084 tcp_connection_t *tc0;
2091 b0 = vlib_get_buffer (vm, bi0);
2093 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2095 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2096 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2098 th0 = tcp_buffer_hdr (b0);
2099 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2108 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2109 u8 is_ip4, u32 evt, u32 val)
2112 vlib_node_increment_counter (vm, tcp4_node, evt, val);
2114 vlib_node_increment_counter (vm, tcp6_node, evt, val);
2117 #define tcp_maybe_inc_counter(node_id, err, count) \
2119 if (next0 != tcp_next_drop (is_ip4)) \
2120 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2121 tcp6_##node_id##_node.index, is_ip4, err, \
2124 #define tcp_inc_counter(node_id, err, count) \
2125 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2126 tcp6_##node_id##_node.index, is_ip4, \
2128 #define tcp_maybe_inc_err_counter(cnts, err) \
2130 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2132 #define tcp_inc_err_counter(cnts, err, val) \
2136 #define tcp_store_err_counters(node_id, cnts) \
2139 for (i = 0; i < TCP_N_ERROR; i++) \
2141 tcp_inc_counter(node_id, i, cnts[i]); \
2146 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2147 vlib_frame_t * frame, int is_ip4)
2149 u32 thread_index = vm->thread_index, errors = 0;
2150 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2151 u32 n_left_from, *from, *first_buffer;
2152 u16 err_counters[TCP_N_ERROR] = { 0 };
2154 if (node->flags & VLIB_NODE_FLAG_TRACE)
2155 tcp_established_trace_frame (vm, node, frame, is_ip4);
2157 first_buffer = from = vlib_frame_vector_args (frame);
2158 n_left_from = frame->n_vectors;
2160 while (n_left_from > 0)
2162 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2165 tcp_connection_t *tc0;
2167 if (n_left_from > 1)
2170 pb = vlib_get_buffer (vm, from[1]);
2171 vlib_prefetch_buffer_header (pb, LOAD);
2172 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2179 b0 = vlib_get_buffer (vm, bi0);
2180 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2183 if (PREDICT_FALSE (tc0 == 0))
2185 error0 = TCP_ERROR_INVALID_CONNECTION;
2189 th0 = tcp_buffer_hdr (b0);
2191 /* TODO header prediction fast path */
2193 /* 1-4: check SEQ, RST, SYN */
2194 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2196 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2200 /* 5: check the ACK field */
2201 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2204 /* 6: check the URG bit TODO */
2206 /* 7: process the segment text */
2207 if (vnet_buffer (b0)->tcp.data_len)
2208 error0 = tcp_segment_rcv (wrk, tc0, b0);
2210 /* 8: check the FIN bit */
2211 if (PREDICT_FALSE (tcp_is_fin (th0)))
2212 tcp_rcv_fin (wrk, tc0, b0, &error0);
2215 tcp_inc_err_counter (err_counters, error0, 1);
2218 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2220 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
2221 tcp_store_err_counters (established, err_counters);
2222 tcp_handle_postponed_dequeues (wrk);
2223 tcp_handle_disconnects (wrk);
2224 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
2226 return frame->n_vectors;
2229 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
2230 vlib_node_runtime_t * node,
2231 vlib_frame_t * from_frame)
2233 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2236 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
2237 vlib_node_runtime_t * node,
2238 vlib_frame_t * from_frame)
2240 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2244 VLIB_REGISTER_NODE (tcp4_established_node) =
2246 .name = "tcp4-established",
2247 /* Takes a vector of packets. */
2248 .vector_size = sizeof (u32),
2249 .n_errors = TCP_N_ERROR,
2250 .error_strings = tcp_error_strings,
2251 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2254 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2255 foreach_tcp_state_next
2258 .format_trace = format_tcp_rx_trace_short,
2263 VLIB_REGISTER_NODE (tcp6_established_node) =
2265 .name = "tcp6-established",
2266 /* Takes a vector of packets. */
2267 .vector_size = sizeof (u32),
2268 .n_errors = TCP_N_ERROR,
2269 .error_strings = tcp_error_strings,
2270 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2273 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2274 foreach_tcp_state_next
2277 .format_trace = format_tcp_rx_trace_short,
2283 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
2286 transport_connection_t *tmp = 0;
2293 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2296 u8 is_ip_valid = 0, val_l, val_r;
2298 if (tc->connection.is_ip4)
2300 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
2302 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
2303 &tc->connection.lcl_ip.ip4);
2304 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
2305 val_r = !ip4_address_compare (&ip4_hdr->src_address,
2306 &tc->connection.rmt_ip.ip4);
2307 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2308 is_ip_valid = val_l && val_r;
2312 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
2314 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
2315 &tc->connection.lcl_ip.ip6);
2316 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
2317 val_r = !ip6_address_compare (&ip6_hdr->src_address,
2318 &tc->connection.rmt_ip.ip6);
2319 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2320 is_ip_valid = val_l && val_r;
2323 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2324 && (tc->state == TCP_STATE_LISTEN
2325 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
2329 handle = session_lookup_half_open_handle (&tc->connection);
2330 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
2331 tc->c_proto, tc->c_is_ip4);
2335 if (tmp->lcl_port == hdr->dst_port
2336 && tmp->rmt_port == hdr->src_port)
2338 TCP_DBG ("half-open is valid!");
2347 * Lookup transport connection
2349 static tcp_connection_t *
2350 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2354 transport_connection_t *tconn;
2355 tcp_connection_t *tc;
2360 ip4 = vlib_buffer_get_current (b);
2361 tcp = ip4_next_header (ip4);
2362 tconn = session_lookup_connection_wt4 (fib_index,
2367 TRANSPORT_PROTO_TCP,
2368 thread_index, &is_filtered);
2369 tc = tcp_get_connection_from_transport (tconn);
2370 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2375 ip6 = vlib_buffer_get_current (b);
2376 tcp = ip6_next_header (ip6);
2377 tconn = session_lookup_connection_wt6 (fib_index,
2382 TRANSPORT_PROTO_TCP,
2383 thread_index, &is_filtered);
2384 tc = tcp_get_connection_from_transport (tconn);
2385 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2390 static tcp_connection_t *
2391 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
2397 ip4_header_t *ip4 = vlib_buffer_get_current (b);
2398 tcp_header_t *tcp = tcp_buffer_hdr (b);
2399 s = session_lookup_listener4 (fib_index,
2401 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
2405 ip6_header_t *ip6 = vlib_buffer_get_current (b);
2406 tcp_header_t *tcp = tcp_buffer_hdr (b);
2407 s = session_lookup_listener6 (fib_index,
2409 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
2412 if (PREDICT_TRUE (s != 0))
2413 return tcp_get_connection_from_transport (transport_get_listener
2414 (TRANSPORT_PROTO_TCP,
2415 s->connection_index));
2421 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
2423 vnet_main_t *vnm = vnet_get_main ();
2424 const dpo_id_t *dpo;
2425 const load_balance_t *lb;
2426 vnet_hw_interface_t *hw_if;
2427 u32 sw_if_idx, lb_idx;
2431 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
2432 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
2436 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
2437 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
2440 lb = load_balance_get (lb_idx);
2441 dpo = load_balance_get_bucket_i (lb, 0);
2443 sw_if_idx = dpo->dpoi_index;
2444 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
2446 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
2447 tc->cfg_flags |= TCP_CFG_F_TSO;
2451 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2452 vlib_frame_t * from_frame, int is_ip4)
2454 u32 n_left_from, *from, *first_buffer, errors = 0;
2455 u32 my_thread_index = vm->thread_index;
2456 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2458 from = first_buffer = vlib_frame_vector_args (from_frame);
2459 n_left_from = from_frame->n_vectors;
2461 while (n_left_from > 0)
2463 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2464 tcp_connection_t *tc0, *new_tc0;
2465 tcp_header_t *tcp0 = 0;
2473 b0 = vlib_get_buffer (vm, bi0);
2475 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2476 if (PREDICT_FALSE (tc0 == 0))
2478 error0 = TCP_ERROR_INVALID_CONNECTION;
2482 /* Half-open completed recently but the connection was't removed
2483 * yet by the owning thread */
2484 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2486 /* Make sure the connection actually exists */
2487 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2488 my_thread_index, is_ip4));
2489 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2493 ack0 = vnet_buffer (b0)->tcp.ack_number;
2494 seq0 = vnet_buffer (b0)->tcp.seq_number;
2495 tcp0 = tcp_buffer_hdr (b0);
2497 /* Crude check to see if the connection handle does not match
2498 * the packet. Probably connection just switched to established */
2499 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2500 || tcp0->src_port != tc0->c_rmt_port))
2502 error0 = TCP_ERROR_INVALID_CONNECTION;
2506 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2507 && !tcp_syn (tcp0)))
2509 error0 = TCP_ERROR_SEGMENT_INVALID;
2513 /* SYNs consume sequence numbers */
2514 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2517 * 1. check the ACK bit
2521 * If the ACK bit is set
2522 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2523 * the RST bit is set, if so drop the segment and return)
2524 * <SEQ=SEG.ACK><CTL=RST>
2525 * and discard the segment. Return.
2526 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2530 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2532 if (!tcp_rst (tcp0))
2533 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2534 error0 = TCP_ERROR_RCV_WND;
2538 /* Make sure ACK is valid */
2539 if (seq_gt (tc0->snd_una, ack0))
2541 error0 = TCP_ERROR_ACK_INVALID;
2547 * 2. check the RST bit
2552 /* If ACK is acceptable, signal client that peer is not
2553 * willing to accept connection and drop connection*/
2555 tcp_connection_reset (tc0);
2556 error0 = TCP_ERROR_RST_RCVD;
2561 * 3. check the security and precedence (skipped)
2565 * 4. check the SYN bit
2568 /* No SYN flag. Drop. */
2569 if (!tcp_syn (tcp0))
2571 error0 = TCP_ERROR_SEGMENT_INVALID;
2576 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2578 error0 = TCP_ERROR_OPTIONS;
2582 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2583 * current thread pool. */
2584 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2585 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2586 new_tc0->irs = seq0;
2587 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2588 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2590 /* If this is not the owning thread, wait for syn retransmit to
2591 * expire and cleanup then */
2592 if (tcp_half_open_connection_cleanup (tc0))
2593 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2595 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2597 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2598 new_tc0->tsval_recent_age = tcp_time_now ();
2601 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2602 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2604 new_tc0->rcv_wscale = 0;
2606 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2607 << new_tc0->snd_wscale;
2608 new_tc0->snd_wl1 = seq0;
2609 new_tc0->snd_wl2 = ack0;
2611 tcp_connection_init_vars (new_tc0);
2613 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2614 if (PREDICT_TRUE (tcp_ack (tcp0)))
2616 /* Our SYN is ACKed: we have iss < ack = snd_una */
2618 /* TODO Dequeue acknowledged segments if we support Fast Open */
2619 new_tc0->snd_una = ack0;
2620 new_tc0->state = TCP_STATE_ESTABLISHED;
2622 /* Make sure las is initialized for the wnd computation */
2623 new_tc0->rcv_las = new_tc0->rcv_nxt;
2625 /* Notify app that we have connection. If session layer can't
2626 * allocate session send reset */
2627 if (session_stream_connect_notify (&new_tc0->connection, 0))
2629 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2630 tcp_connection_cleanup (new_tc0);
2631 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2635 new_tc0->tx_fifo_size =
2636 transport_tx_fifo_size (&new_tc0->connection);
2637 /* Update rtt with the syn-ack sample */
2638 tcp_estimate_initial_rtt (new_tc0);
2639 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2640 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2642 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2645 new_tc0->state = TCP_STATE_SYN_RCVD;
2647 /* Notify app that we have connection */
2648 if (session_stream_connect_notify (&new_tc0->connection, 0))
2650 tcp_connection_cleanup (new_tc0);
2651 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2652 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2653 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2657 new_tc0->tx_fifo_size =
2658 transport_tx_fifo_size (&new_tc0->connection);
2659 new_tc0->rtt_ts = 0;
2660 tcp_init_snd_vars (new_tc0);
2661 tcp_send_synack (new_tc0);
2662 error0 = TCP_ERROR_SYNS_RCVD;
2666 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2667 tcp_check_tx_offload (new_tc0, is_ip4);
2669 /* Read data, if any */
2670 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2672 clib_warning ("rcvd data in syn-sent");
2673 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2674 if (error0 == TCP_ERROR_ACK_OK)
2675 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2679 /* Send ack now instead of programming it because connection was
2680 * just established and it's not optional. */
2681 tcp_send_ack (new_tc0);
2686 tcp_inc_counter (syn_sent, error0, 1);
2687 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2689 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2690 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2691 clib_memcpy_fast (&t0->tcp_connection, tc0,
2692 sizeof (t0->tcp_connection));
2696 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2698 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2699 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2701 return from_frame->n_vectors;
2704 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2705 vlib_node_runtime_t * node,
2706 vlib_frame_t * from_frame)
2708 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2711 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2712 vlib_node_runtime_t * node,
2713 vlib_frame_t * from_frame)
2715 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2719 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2721 .name = "tcp4-syn-sent",
2722 /* Takes a vector of packets. */
2723 .vector_size = sizeof (u32),
2724 .n_errors = TCP_N_ERROR,
2725 .error_strings = tcp_error_strings,
2726 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2729 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2730 foreach_tcp_state_next
2733 .format_trace = format_tcp_rx_trace_short,
2738 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2740 .name = "tcp6-syn-sent",
2741 /* Takes a vector of packets. */
2742 .vector_size = sizeof (u32),
2743 .n_errors = TCP_N_ERROR,
2744 .error_strings = tcp_error_strings,
2745 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2748 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2749 foreach_tcp_state_next
2752 .format_trace = format_tcp_rx_trace_short,
2757 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2758 * as per RFC793 p. 64
2761 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2762 vlib_frame_t * from_frame, int is_ip4)
2764 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2765 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2766 u32 n_left_from, *from, max_dequeue;
2768 from = first_buffer = vlib_frame_vector_args (from_frame);
2769 n_left_from = from_frame->n_vectors;
2771 while (n_left_from > 0)
2773 u32 bi0, error0 = TCP_ERROR_NONE;
2774 tcp_header_t *tcp0 = 0;
2775 tcp_connection_t *tc0;
2783 b0 = vlib_get_buffer (vm, bi0);
2784 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2786 if (PREDICT_FALSE (tc0 == 0))
2788 error0 = TCP_ERROR_INVALID_CONNECTION;
2792 tcp0 = tcp_buffer_hdr (b0);
2793 is_fin0 = tcp_is_fin (tcp0);
2797 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2799 tcp_connection_t *tmp;
2800 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2802 if (tmp->state != tc0->state)
2804 if (tc0->state != TCP_STATE_CLOSED)
2805 clib_warning ("state changed");
2812 * Special treatment for CLOSED
2814 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2816 error0 = TCP_ERROR_CONNECTION_CLOSED;
2821 * For all other states (except LISTEN)
2824 /* 1-4: check SEQ, RST, SYN */
2825 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2828 /* 5: check the ACK field */
2831 case TCP_STATE_SYN_RCVD:
2833 /* Make sure the segment is exactly right */
2834 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2836 tcp_connection_reset (tc0);
2837 error0 = TCP_ERROR_SEGMENT_INVALID;
2842 * If the segment acknowledgment is not acceptable, form a
2844 * <SEQ=SEG.ACK><CTL=RST>
2847 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2849 tcp_connection_reset (tc0);
2853 /* Update rtt and rto */
2854 tcp_estimate_initial_rtt (tc0);
2855 tcp_connection_tx_pacer_update (tc0);
2857 /* Switch state to ESTABLISHED */
2858 tc0->state = TCP_STATE_ESTABLISHED;
2859 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2861 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2862 tcp_check_tx_offload (tc0, is_ip4);
2864 /* Initialize session variables */
2865 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2866 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2867 << tc0->rcv_opts.wscale;
2868 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2869 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2871 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2872 tcp_retransmit_timer_reset (tc0);
2873 if (session_stream_accept_notify (&tc0->connection))
2875 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2876 tcp_connection_reset (tc0);
2879 error0 = TCP_ERROR_ACK_OK;
2881 case TCP_STATE_ESTABLISHED:
2882 /* We can get packets in established state here because they
2883 * were enqueued before state change */
2884 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2888 case TCP_STATE_FIN_WAIT_1:
2889 /* In addition to the processing for the ESTABLISHED state, if
2890 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2891 * continue processing in that state. */
2892 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2895 /* Still have to send the FIN */
2896 if (tc0->flags & TCP_CONN_FINPNDG)
2898 /* TX fifo finally drained */
2899 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2900 if (max_dequeue <= tc0->burst_acked)
2902 /* If a fin was received and data was acked extend wait */
2903 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2904 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2905 tcp_cfg.closewait_time);
2907 /* If FIN is ACKed */
2908 else if (tc0->snd_una == tc0->snd_nxt)
2910 /* Stop all retransmit timers because we have nothing more
2912 tcp_connection_timers_reset (tc0);
2914 /* We already have a FIN but didn't transition to CLOSING
2915 * because of outstanding tx data. Close the connection. */
2916 if (tc0->flags & TCP_CONN_FINRCVD)
2918 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2919 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE,
2920 tcp_cfg.cleanup_time);
2921 session_transport_closed_notify (&tc0->connection);
2925 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2926 /* Enable waitclose because we're willing to wait for peer's
2927 * FIN but not indefinitely. */
2928 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2930 /* Don't try to deq the FIN acked */
2931 if (tc0->burst_acked > 1)
2932 session_tx_fifo_dequeue_drop (&tc0->connection,
2933 tc0->burst_acked - 1);
2934 tc0->burst_acked = 0;
2937 case TCP_STATE_FIN_WAIT_2:
2938 /* In addition to the processing for the ESTABLISHED state, if
2939 * the retransmission queue is empty, the user's CLOSE can be
2940 * acknowledged ("ok") but do not delete the TCB. */
2941 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2943 tc0->burst_acked = 0;
2945 case TCP_STATE_CLOSE_WAIT:
2946 /* Do the same processing as for the ESTABLISHED state. */
2947 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2950 if (!(tc0->flags & TCP_CONN_FINPNDG))
2953 /* Still have outstanding tx data */
2954 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2955 if (max_dequeue > tc0->burst_acked)
2959 tcp_connection_timers_reset (tc0);
2960 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2961 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2963 case TCP_STATE_CLOSING:
2964 /* In addition to the processing for the ESTABLISHED state, if
2965 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2966 * otherwise ignore the segment. */
2967 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2970 if (tc0->snd_una != tc0->snd_nxt)
2973 tcp_connection_timers_reset (tc0);
2974 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2975 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2976 session_transport_closed_notify (&tc0->connection);
2980 case TCP_STATE_LAST_ACK:
2981 /* The only thing that [should] arrive in this state is an
2982 * acknowledgment of our FIN. If our FIN is now acknowledged,
2983 * delete the TCB, enter the CLOSED state, and return. */
2985 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2988 /* Apparently our ACK for the peer's FIN was lost */
2989 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2995 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2996 session_transport_closed_notify (&tc0->connection);
2998 /* Don't free the connection from the data path since
2999 * we can't ensure that we have no packets already enqueued
3000 * to output. Rely instead on the waitclose timer */
3001 tcp_connection_timers_reset (tc0);
3002 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
3007 case TCP_STATE_TIME_WAIT:
3008 /* The only thing that can arrive in this state is a
3009 * retransmission of the remote FIN. Acknowledge it, and restart
3010 * the 2 MSL timeout. */
3012 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3018 tcp_program_ack (tc0);
3019 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3027 /* 6: check the URG bit TODO */
3029 /* 7: process the segment text */
3032 case TCP_STATE_ESTABLISHED:
3033 case TCP_STATE_FIN_WAIT_1:
3034 case TCP_STATE_FIN_WAIT_2:
3035 if (vnet_buffer (b0)->tcp.data_len)
3036 error0 = tcp_segment_rcv (wrk, tc0, b0);
3038 case TCP_STATE_CLOSE_WAIT:
3039 case TCP_STATE_CLOSING:
3040 case TCP_STATE_LAST_ACK:
3041 case TCP_STATE_TIME_WAIT:
3042 /* This should not occur, since a FIN has been received from the
3043 * remote side. Ignore the segment text. */
3047 /* 8: check the FIN bit */
3051 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
3055 case TCP_STATE_ESTABLISHED:
3056 /* Account for the FIN and send ack */
3058 tcp_program_ack (tc0);
3059 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
3060 tcp_program_disconnect (wrk, tc0);
3061 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
3063 case TCP_STATE_SYN_RCVD:
3064 /* Send FIN-ACK, enter LAST-ACK and because the app was not
3065 * notified yet, set a cleanup timer instead of relying on
3066 * disconnect notify and the implicit close call. */
3067 tcp_connection_timers_reset (tc0);
3070 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3071 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3073 case TCP_STATE_CLOSE_WAIT:
3074 case TCP_STATE_CLOSING:
3075 case TCP_STATE_LAST_ACK:
3078 case TCP_STATE_FIN_WAIT_1:
3081 if (tc0->flags & TCP_CONN_FINPNDG)
3083 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
3084 * sending it. Since we already received a fin, do not wait
3086 tc0->flags |= TCP_CONN_FINRCVD;
3087 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3088 tcp_cfg.closewait_time);
3092 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
3093 tcp_program_ack (tc0);
3094 /* Wait for ACK for our FIN but not forever */
3095 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3096 tcp_cfg.closing_time);
3099 case TCP_STATE_FIN_WAIT_2:
3100 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
3102 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3103 tcp_connection_timers_reset (tc0);
3104 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3105 tcp_program_ack (tc0);
3106 session_transport_closed_notify (&tc0->connection);
3108 case TCP_STATE_TIME_WAIT:
3109 /* Remain in the TIME-WAIT state. Restart the time-wait
3112 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3115 error0 = TCP_ERROR_FIN_RCVD;
3119 tcp_inc_counter (rcv_process, error0, 1);
3120 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3122 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3123 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
3127 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
3129 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
3130 tcp_handle_postponed_dequeues (wrk);
3131 tcp_handle_disconnects (wrk);
3132 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3134 return from_frame->n_vectors;
3137 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
3138 vlib_node_runtime_t * node,
3139 vlib_frame_t * from_frame)
3141 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3144 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
3145 vlib_node_runtime_t * node,
3146 vlib_frame_t * from_frame)
3148 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3152 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
3154 .name = "tcp4-rcv-process",
3155 /* Takes a vector of packets. */
3156 .vector_size = sizeof (u32),
3157 .n_errors = TCP_N_ERROR,
3158 .error_strings = tcp_error_strings,
3159 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3162 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3163 foreach_tcp_state_next
3166 .format_trace = format_tcp_rx_trace_short,
3171 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3173 .name = "tcp6-rcv-process",
3174 /* Takes a vector of packets. */
3175 .vector_size = sizeof (u32),
3176 .n_errors = TCP_N_ERROR,
3177 .error_strings = tcp_error_strings,
3178 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3181 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3182 foreach_tcp_state_next
3185 .format_trace = format_tcp_rx_trace_short,
3190 * LISTEN state processing as per RFC 793 p. 65
3193 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3194 vlib_frame_t * from_frame, int is_ip4)
3196 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3197 u32 my_thread_index = vm->thread_index;
3198 tcp_connection_t *tc0;
3200 from = first_buffer = vlib_frame_vector_args (from_frame);
3201 n_left_from = from_frame->n_vectors;
3203 while (n_left_from > 0)
3208 tcp_header_t *th0 = 0;
3209 tcp_connection_t *lc0;
3212 tcp_connection_t *child0;
3213 u32 error0 = TCP_ERROR_NONE;
3219 b0 = vlib_get_buffer (vm, bi0);
3220 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3221 if (PREDICT_FALSE (lc0 == 0))
3223 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
3225 if (tc0->state != TCP_STATE_TIME_WAIT)
3227 error0 = TCP_ERROR_CREATE_EXISTS;
3230 lc0 = tcp_lookup_listener (b0, tc0->c_fib_index, is_ip4);
3231 /* clean up the old session */
3232 tcp_connection_del (tc0);
3237 ip40 = vlib_buffer_get_current (b0);
3238 th0 = tcp_buffer_hdr (b0);
3242 ip60 = vlib_buffer_get_current (b0);
3243 th0 = tcp_buffer_hdr (b0);
3246 /* Create child session. For syn-flood protection use filter */
3248 /* 1. first check for an RST: handled in dispatch */
3249 /* if (tcp_rst (th0))
3253 /* 2. second check for an ACK: handled in dispatch */
3254 /* if (tcp_ack (th0))
3256 tcp_send_reset (b0, is_ip4);
3261 /* 3. check for a SYN (did that already) */
3263 /* Make sure connection wasn't just created */
3264 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3266 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3268 error0 = TCP_ERROR_CREATE_EXISTS;
3272 /* Create child session and send SYN-ACK */
3273 child0 = tcp_connection_alloc (my_thread_index);
3274 child0->c_lcl_port = th0->dst_port;
3275 child0->c_rmt_port = th0->src_port;
3276 child0->c_is_ip4 = is_ip4;
3277 child0->state = TCP_STATE_SYN_RCVD;
3278 child0->c_fib_index = lc0->c_fib_index;
3279 child0->cc_algo = lc0->cc_algo;
3283 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3284 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3288 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3289 sizeof (ip6_address_t));
3290 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3291 sizeof (ip6_address_t));
3294 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3296 error0 = TCP_ERROR_OPTIONS;
3297 tcp_connection_free (child0);
3301 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3302 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3303 child0->rcv_las = child0->rcv_nxt;
3304 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3306 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3307 * segments are used to initialize PAWS. */
3308 if (tcp_opts_tstamp (&child0->rcv_opts))
3310 child0->tsval_recent = child0->rcv_opts.tsval;
3311 child0->tsval_recent_age = tcp_time_now ();
3314 if (tcp_opts_wscale (&child0->rcv_opts))
3315 child0->snd_wscale = child0->rcv_opts.wscale;
3317 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3318 << child0->snd_wscale;
3319 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3320 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3322 tcp_connection_init_vars (child0);
3323 child0->rto = TCP_RTO_MIN;
3325 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3326 lc0->c_thread_index, 0 /* notify */ ))
3328 tcp_connection_cleanup (child0);
3329 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3333 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3334 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3335 tcp_send_synack (child0);
3339 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3341 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3342 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3343 clib_memcpy_fast (&t0->tcp_connection, lc0,
3344 sizeof (t0->tcp_connection));
3347 n_syns += (error0 == TCP_ERROR_NONE);
3350 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3351 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3353 return from_frame->n_vectors;
3356 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3357 vlib_frame_t * from_frame)
3359 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3362 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3363 vlib_frame_t * from_frame)
3365 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3369 VLIB_REGISTER_NODE (tcp4_listen_node) =
3371 .name = "tcp4-listen",
3372 /* Takes a vector of packets. */
3373 .vector_size = sizeof (u32),
3374 .n_errors = TCP_N_ERROR,
3375 .error_strings = tcp_error_strings,
3376 .n_next_nodes = TCP_LISTEN_N_NEXT,
3379 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3380 foreach_tcp_state_next
3383 .format_trace = format_tcp_rx_trace_short,
3388 VLIB_REGISTER_NODE (tcp6_listen_node) =
3390 .name = "tcp6-listen",
3391 /* Takes a vector of packets. */
3392 .vector_size = sizeof (u32),
3393 .n_errors = TCP_N_ERROR,
3394 .error_strings = tcp_error_strings,
3395 .n_next_nodes = TCP_LISTEN_N_NEXT,
3398 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3399 foreach_tcp_state_next
3402 .format_trace = format_tcp_rx_trace_short,
3406 typedef enum _tcp_input_next
3408 TCP_INPUT_NEXT_DROP,
3409 TCP_INPUT_NEXT_LISTEN,
3410 TCP_INPUT_NEXT_RCV_PROCESS,
3411 TCP_INPUT_NEXT_SYN_SENT,
3412 TCP_INPUT_NEXT_ESTABLISHED,
3413 TCP_INPUT_NEXT_RESET,
3414 TCP_INPUT_NEXT_PUNT,
3418 #define foreach_tcp4_input_next \
3419 _ (DROP, "ip4-drop") \
3420 _ (LISTEN, "tcp4-listen") \
3421 _ (RCV_PROCESS, "tcp4-rcv-process") \
3422 _ (SYN_SENT, "tcp4-syn-sent") \
3423 _ (ESTABLISHED, "tcp4-established") \
3424 _ (RESET, "tcp4-reset") \
3425 _ (PUNT, "ip4-punt")
3427 #define foreach_tcp6_input_next \
3428 _ (DROP, "ip6-drop") \
3429 _ (LISTEN, "tcp6-listen") \
3430 _ (RCV_PROCESS, "tcp6-rcv-process") \
3431 _ (SYN_SENT, "tcp6-syn-sent") \
3432 _ (ESTABLISHED, "tcp6-established") \
3433 _ (RESET, "tcp6-reset") \
3434 _ (PUNT, "ip6-punt")
3436 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3439 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3440 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3442 tcp_connection_t *tc;
3447 for (i = 0; i < n_bufs; i++)
3449 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3451 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3452 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3454 tcp = vlib_buffer_get_current (bs[i]);
3455 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3461 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3463 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3465 *next = TCP_INPUT_NEXT_DROP;
3467 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3469 *next = TCP_INPUT_NEXT_PUNT;
3470 *error = TCP_ERROR_PUNT;
3474 *next = TCP_INPUT_NEXT_RESET;
3475 *error = TCP_ERROR_NO_LISTENER;
3479 always_inline tcp_connection_t *
3480 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3481 u8 is_ip4, u8 is_nolookup)
3483 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3484 int n_advance_bytes, n_data_bytes;
3485 transport_connection_t *tc;
3491 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3492 int ip_hdr_bytes = ip4_header_bytes (ip4);
3493 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3495 *error = TCP_ERROR_LENGTH;
3498 tcp = ip4_next_header (ip4);
3499 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3500 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3501 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3503 /* Length check. Checksum computed by ipx_local no need to compute again */
3504 if (PREDICT_FALSE (n_data_bytes < 0))
3506 *error = TCP_ERROR_LENGTH;
3511 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3512 &ip4->src_address, tcp->dst_port,
3514 TRANSPORT_PROTO_TCP, thread_index,
3519 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3520 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3522 *error = TCP_ERROR_LENGTH;
3525 tcp = ip6_next_header (ip6);
3526 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3527 n_advance_bytes = tcp_header_bytes (tcp);
3528 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3530 n_advance_bytes += sizeof (ip6[0]);
3532 if (PREDICT_FALSE (n_data_bytes < 0))
3534 *error = TCP_ERROR_LENGTH;
3541 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3543 ip4_main_t *im = &ip4_main;
3544 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3545 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3548 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3550 tcp->dst_port, tcp->src_port,
3551 TRANSPORT_PROTO_TCP,
3552 thread_index, &result);
3558 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3559 tcp.connection_index,
3562 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3563 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3564 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3565 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3566 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3568 vnet_buffer (b)->tcp.flags = 0;
3570 *error = result ? TCP_ERROR_NONE + result : *error;
3572 return tcp_get_connection_from_transport (tc);
3576 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3577 vlib_buffer_t * b, u16 * next, u32 * error)
3582 tcp = tcp_buffer_hdr (b);
3583 flags = tcp->flags & filter_flags;
3584 *next = tm->dispatch_table[tc->state][flags].next;
3585 *error = tm->dispatch_table[tc->state][flags].error;
3588 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3589 || *next == TCP_INPUT_NEXT_RESET))
3591 /* Overload tcp flags to store state */
3592 tcp_state_t state = tc->state;
3593 vnet_buffer (b)->tcp.flags = tc->state;
3595 if (*error == TCP_ERROR_DISPATCH)
3596 clib_warning ("tcp conn %u disp error state %U flags %U",
3597 tc->c_c_index, format_tcp_state, state,
3598 format_tcp_flags, (int) flags);
3603 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3604 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3606 u32 n_left_from, *from, thread_index = vm->thread_index;
3607 tcp_main_t *tm = vnet_get_tcp_main ();
3608 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3609 u16 nexts[VLIB_FRAME_SIZE], *next;
3611 tcp_set_time_now (tcp_get_worker (thread_index));
3613 from = vlib_frame_vector_args (frame);
3614 n_left_from = frame->n_vectors;
3615 vlib_get_buffers (vm, from, bufs, n_left_from);
3620 while (n_left_from >= 4)
3622 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3623 tcp_connection_t *tc0, *tc1;
3626 vlib_prefetch_buffer_header (b[2], STORE);
3627 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3629 vlib_prefetch_buffer_header (b[3], STORE);
3630 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3633 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3635 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3637 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3640 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3642 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3643 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3645 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3646 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3648 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3649 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3653 if (PREDICT_TRUE (tc0 != 0))
3655 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3656 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3657 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3660 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3662 if (PREDICT_TRUE (tc1 != 0))
3664 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3665 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3666 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3669 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3676 while (n_left_from > 0)
3678 tcp_connection_t *tc0;
3679 u32 error0 = TCP_ERROR_NO_LISTENER;
3681 if (n_left_from > 1)
3683 vlib_prefetch_buffer_header (b[1], STORE);
3684 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3687 next[0] = TCP_INPUT_NEXT_DROP;
3688 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3690 if (PREDICT_TRUE (tc0 != 0))
3692 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3693 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3694 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3697 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3704 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3705 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3707 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3708 return frame->n_vectors;
3711 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3712 vlib_node_runtime_t * node,
3713 vlib_frame_t * from_frame)
3715 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3716 1 /* is_nolookup */ );
3719 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3720 vlib_node_runtime_t * node,
3721 vlib_frame_t * from_frame)
3723 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3724 1 /* is_nolookup */ );
3728 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3730 .name = "tcp4-input-nolookup",
3731 /* Takes a vector of packets. */
3732 .vector_size = sizeof (u32),
3733 .n_errors = TCP_N_ERROR,
3734 .error_strings = tcp_error_strings,
3735 .n_next_nodes = TCP_INPUT_N_NEXT,
3738 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3739 foreach_tcp4_input_next
3742 .format_buffer = format_tcp_header,
3743 .format_trace = format_tcp_rx_trace,
3748 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3750 .name = "tcp6-input-nolookup",
3751 /* Takes a vector of packets. */
3752 .vector_size = sizeof (u32),
3753 .n_errors = TCP_N_ERROR,
3754 .error_strings = tcp_error_strings,
3755 .n_next_nodes = TCP_INPUT_N_NEXT,
3758 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3759 foreach_tcp6_input_next
3762 .format_buffer = format_tcp_header,
3763 .format_trace = format_tcp_rx_trace,
3767 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3768 vlib_frame_t * from_frame)
3770 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3771 0 /* is_nolookup */ );
3774 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3775 vlib_frame_t * from_frame)
3777 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3778 0 /* is_nolookup */ );
3782 VLIB_REGISTER_NODE (tcp4_input_node) =
3784 .name = "tcp4-input",
3785 /* Takes a vector of packets. */
3786 .vector_size = sizeof (u32),
3787 .n_errors = TCP_N_ERROR,
3788 .error_strings = tcp_error_strings,
3789 .n_next_nodes = TCP_INPUT_N_NEXT,
3792 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3793 foreach_tcp4_input_next
3796 .format_buffer = format_tcp_header,
3797 .format_trace = format_tcp_rx_trace,
3802 VLIB_REGISTER_NODE (tcp6_input_node) =
3804 .name = "tcp6-input",
3805 /* Takes a vector of packets. */
3806 .vector_size = sizeof (u32),
3807 .n_errors = TCP_N_ERROR,
3808 .error_strings = tcp_error_strings,
3809 .n_next_nodes = TCP_INPUT_N_NEXT,
3812 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3813 foreach_tcp6_input_next
3816 .format_buffer = format_tcp_header,
3817 .format_trace = format_tcp_rx_trace,
3821 #ifndef CLIB_MARCH_VARIANT
3823 tcp_dispatch_table_init (tcp_main_t * tm)
3826 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3827 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3829 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3830 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3833 #define _(t,f,n,e) \
3835 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3836 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3839 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3840 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3841 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3842 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3843 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3844 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3845 TCP_ERROR_ACK_INVALID);
3846 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3847 TCP_ERROR_SEGMENT_INVALID);
3848 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3849 TCP_ERROR_SEGMENT_INVALID);
3850 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3851 TCP_ERROR_INVALID_CONNECTION);
3852 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3853 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3854 TCP_ERROR_SEGMENT_INVALID);
3855 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3856 TCP_ERROR_SEGMENT_INVALID);
3857 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3859 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3860 TCP_ERROR_SEGMENT_INVALID);
3861 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3862 TCP_ERROR_SEGMENT_INVALID);
3863 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3864 TCP_ERROR_SEGMENT_INVALID);
3865 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3866 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3867 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3868 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3869 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3870 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3872 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3873 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3875 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3877 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3878 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3879 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3880 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3882 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3884 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3885 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3886 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3888 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3889 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3890 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3891 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3892 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3893 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3894 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3895 /* SYN-ACK for a SYN */
3896 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3898 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3899 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3900 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3902 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3903 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3905 /* ACK for for established connection -> tcp-established. */
3906 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3907 /* FIN for for established connection -> tcp-established. */
3908 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3909 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3911 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3913 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3914 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3915 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3917 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3918 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3919 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3920 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3921 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3922 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3923 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3924 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3926 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3927 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3929 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3931 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3932 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3933 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3934 /* ACK or FIN-ACK to our FIN */
3935 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3936 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3938 /* FIN in reply to our FIN from the other side */
3939 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3940 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3941 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3943 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3944 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3945 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3946 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3947 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3948 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3949 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3951 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3952 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3953 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3954 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3956 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3958 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3959 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3960 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3961 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3963 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3964 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3965 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3966 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3968 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3970 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3971 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3972 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3973 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3975 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3976 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3978 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3980 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3981 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3982 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3984 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3985 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3986 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3987 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3988 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3989 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3990 /* FIN confirming that the peer (app) has closed */
3991 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3992 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3993 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3995 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3996 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3998 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3999 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4001 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4002 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4004 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4005 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4006 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4007 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4009 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4011 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4012 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4013 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4015 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4016 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4017 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4018 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4019 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4020 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4021 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4022 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4024 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4025 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4027 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4029 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4030 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4031 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
4032 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4033 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4035 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4036 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4038 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4039 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
4040 * incoming segment not containing a RST causes a RST to be sent in
4042 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
4043 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
4044 TCP_ERROR_CONNECTION_CLOSED);
4045 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
4046 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
4047 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
4052 static clib_error_t *
4053 tcp_input_init (vlib_main_t * vm)
4055 clib_error_t *error = 0;
4056 tcp_main_t *tm = vnet_get_tcp_main ();
4058 if ((error = vlib_call_init_function (vm, tcp_init)))
4061 /* Initialize dispatch table. */
4062 tcp_dispatch_table_init (tm);
4067 VLIB_INIT_FUNCTION (tcp_input_init);
4069 #endif /* CLIB_MARCH_VARIANT */
4072 * fd.io coding-style-patch-verification: ON
4075 * eval: (c-set-style "gnu")