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) && !sb->sacked_bytes
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);
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 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
2443 dpo = load_balance_get_bucket_i (lb, 0);
2445 sw_if_idx = dpo_get_urpf (dpo);
2446 if (PREDICT_FALSE (sw_if_idx == ~0))
2449 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
2450 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
2451 tc->cfg_flags |= TCP_CFG_F_TSO;
2455 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2456 vlib_frame_t * from_frame, int is_ip4)
2458 u32 n_left_from, *from, *first_buffer, errors = 0;
2459 u32 my_thread_index = vm->thread_index;
2460 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2462 from = first_buffer = vlib_frame_vector_args (from_frame);
2463 n_left_from = from_frame->n_vectors;
2465 while (n_left_from > 0)
2467 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2468 tcp_connection_t *tc0, *new_tc0;
2469 tcp_header_t *tcp0 = 0;
2477 b0 = vlib_get_buffer (vm, bi0);
2479 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2480 if (PREDICT_FALSE (tc0 == 0))
2482 error0 = TCP_ERROR_INVALID_CONNECTION;
2486 /* Half-open completed recently but the connection was't removed
2487 * yet by the owning thread */
2488 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2490 /* Make sure the connection actually exists */
2491 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2492 my_thread_index, is_ip4));
2493 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2497 ack0 = vnet_buffer (b0)->tcp.ack_number;
2498 seq0 = vnet_buffer (b0)->tcp.seq_number;
2499 tcp0 = tcp_buffer_hdr (b0);
2501 /* Crude check to see if the connection handle does not match
2502 * the packet. Probably connection just switched to established */
2503 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2504 || tcp0->src_port != tc0->c_rmt_port))
2506 error0 = TCP_ERROR_INVALID_CONNECTION;
2510 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2511 && !tcp_syn (tcp0)))
2513 error0 = TCP_ERROR_SEGMENT_INVALID;
2517 /* SYNs consume sequence numbers */
2518 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2521 * 1. check the ACK bit
2525 * If the ACK bit is set
2526 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2527 * the RST bit is set, if so drop the segment and return)
2528 * <SEQ=SEG.ACK><CTL=RST>
2529 * and discard the segment. Return.
2530 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2534 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2536 if (!tcp_rst (tcp0))
2537 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2538 error0 = TCP_ERROR_RCV_WND;
2542 /* Make sure ACK is valid */
2543 if (seq_gt (tc0->snd_una, ack0))
2545 error0 = TCP_ERROR_ACK_INVALID;
2551 * 2. check the RST bit
2556 /* If ACK is acceptable, signal client that peer is not
2557 * willing to accept connection and drop connection*/
2559 tcp_connection_reset (tc0);
2560 error0 = TCP_ERROR_RST_RCVD;
2565 * 3. check the security and precedence (skipped)
2569 * 4. check the SYN bit
2572 /* No SYN flag. Drop. */
2573 if (!tcp_syn (tcp0))
2575 error0 = TCP_ERROR_SEGMENT_INVALID;
2580 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2582 error0 = TCP_ERROR_OPTIONS;
2586 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2587 * current thread pool. */
2588 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2589 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2590 new_tc0->irs = seq0;
2591 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2592 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2594 /* If this is not the owning thread, wait for syn retransmit to
2595 * expire and cleanup then */
2596 if (tcp_half_open_connection_cleanup (tc0))
2597 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2599 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2601 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2602 new_tc0->tsval_recent_age = tcp_time_now ();
2605 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2606 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2608 new_tc0->rcv_wscale = 0;
2610 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2611 << new_tc0->snd_wscale;
2612 new_tc0->snd_wl1 = seq0;
2613 new_tc0->snd_wl2 = ack0;
2615 tcp_connection_init_vars (new_tc0);
2617 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2618 if (PREDICT_TRUE (tcp_ack (tcp0)))
2620 /* Our SYN is ACKed: we have iss < ack = snd_una */
2622 /* TODO Dequeue acknowledged segments if we support Fast Open */
2623 new_tc0->snd_una = ack0;
2624 new_tc0->state = TCP_STATE_ESTABLISHED;
2626 /* Make sure las is initialized for the wnd computation */
2627 new_tc0->rcv_las = new_tc0->rcv_nxt;
2629 /* Notify app that we have connection. If session layer can't
2630 * allocate session send reset */
2631 if (session_stream_connect_notify (&new_tc0->connection, 0))
2633 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2634 tcp_connection_cleanup (new_tc0);
2635 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2639 new_tc0->tx_fifo_size =
2640 transport_tx_fifo_size (&new_tc0->connection);
2641 /* Update rtt with the syn-ack sample */
2642 tcp_estimate_initial_rtt (new_tc0);
2643 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2644 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2646 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2649 new_tc0->state = TCP_STATE_SYN_RCVD;
2651 /* Notify app that we have connection */
2652 if (session_stream_connect_notify (&new_tc0->connection, 0))
2654 tcp_connection_cleanup (new_tc0);
2655 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2656 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2657 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2661 new_tc0->tx_fifo_size =
2662 transport_tx_fifo_size (&new_tc0->connection);
2663 new_tc0->rtt_ts = 0;
2664 tcp_init_snd_vars (new_tc0);
2665 tcp_send_synack (new_tc0);
2666 error0 = TCP_ERROR_SYNS_RCVD;
2670 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2671 tcp_check_tx_offload (new_tc0, is_ip4);
2673 /* Read data, if any */
2674 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2676 clib_warning ("rcvd data in syn-sent");
2677 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2678 if (error0 == TCP_ERROR_ACK_OK)
2679 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2683 /* Send ack now instead of programming it because connection was
2684 * just established and it's not optional. */
2685 tcp_send_ack (new_tc0);
2690 tcp_inc_counter (syn_sent, error0, 1);
2691 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2693 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2694 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2695 clib_memcpy_fast (&t0->tcp_connection, tc0,
2696 sizeof (t0->tcp_connection));
2700 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2702 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2703 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2705 return from_frame->n_vectors;
2708 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2709 vlib_node_runtime_t * node,
2710 vlib_frame_t * from_frame)
2712 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2715 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2716 vlib_node_runtime_t * node,
2717 vlib_frame_t * from_frame)
2719 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2723 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2725 .name = "tcp4-syn-sent",
2726 /* Takes a vector of packets. */
2727 .vector_size = sizeof (u32),
2728 .n_errors = TCP_N_ERROR,
2729 .error_strings = tcp_error_strings,
2730 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2733 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2734 foreach_tcp_state_next
2737 .format_trace = format_tcp_rx_trace_short,
2742 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2744 .name = "tcp6-syn-sent",
2745 /* Takes a vector of packets. */
2746 .vector_size = sizeof (u32),
2747 .n_errors = TCP_N_ERROR,
2748 .error_strings = tcp_error_strings,
2749 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2752 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2753 foreach_tcp_state_next
2756 .format_trace = format_tcp_rx_trace_short,
2761 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2762 * as per RFC793 p. 64
2765 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2766 vlib_frame_t * from_frame, int is_ip4)
2768 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2769 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2770 u32 n_left_from, *from, max_dequeue;
2772 from = first_buffer = vlib_frame_vector_args (from_frame);
2773 n_left_from = from_frame->n_vectors;
2775 while (n_left_from > 0)
2777 u32 bi0, error0 = TCP_ERROR_NONE;
2778 tcp_header_t *tcp0 = 0;
2779 tcp_connection_t *tc0;
2787 b0 = vlib_get_buffer (vm, bi0);
2788 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2790 if (PREDICT_FALSE (tc0 == 0))
2792 error0 = TCP_ERROR_INVALID_CONNECTION;
2796 tcp0 = tcp_buffer_hdr (b0);
2797 is_fin0 = tcp_is_fin (tcp0);
2801 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2803 tcp_connection_t *tmp;
2804 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2806 if (tmp->state != tc0->state)
2808 if (tc0->state != TCP_STATE_CLOSED)
2809 clib_warning ("state changed");
2816 * Special treatment for CLOSED
2818 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2820 error0 = TCP_ERROR_CONNECTION_CLOSED;
2825 * For all other states (except LISTEN)
2828 /* 1-4: check SEQ, RST, SYN */
2829 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2832 /* 5: check the ACK field */
2835 case TCP_STATE_SYN_RCVD:
2837 /* Make sure the segment is exactly right */
2838 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2840 tcp_connection_reset (tc0);
2841 error0 = TCP_ERROR_SEGMENT_INVALID;
2846 * If the segment acknowledgment is not acceptable, form a
2848 * <SEQ=SEG.ACK><CTL=RST>
2851 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2853 tcp_connection_reset (tc0);
2857 /* Update rtt and rto */
2858 tcp_estimate_initial_rtt (tc0);
2859 tcp_connection_tx_pacer_update (tc0);
2861 /* Switch state to ESTABLISHED */
2862 tc0->state = TCP_STATE_ESTABLISHED;
2863 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2865 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2866 tcp_check_tx_offload (tc0, is_ip4);
2868 /* Initialize session variables */
2869 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2870 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2871 << tc0->rcv_opts.wscale;
2872 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2873 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2875 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2876 tcp_retransmit_timer_reset (tc0);
2877 if (session_stream_accept_notify (&tc0->connection))
2879 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2880 tcp_connection_reset (tc0);
2883 error0 = TCP_ERROR_ACK_OK;
2885 case TCP_STATE_ESTABLISHED:
2886 /* We can get packets in established state here because they
2887 * were enqueued before state change */
2888 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2892 case TCP_STATE_FIN_WAIT_1:
2893 /* In addition to the processing for the ESTABLISHED state, if
2894 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2895 * continue processing in that state. */
2896 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2899 /* Still have to send the FIN */
2900 if (tc0->flags & TCP_CONN_FINPNDG)
2902 /* TX fifo finally drained */
2903 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2904 if (max_dequeue <= tc0->burst_acked)
2906 /* If a fin was received and data was acked extend wait */
2907 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2908 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2909 tcp_cfg.closewait_time);
2911 /* If FIN is ACKed */
2912 else if (tc0->snd_una == tc0->snd_nxt)
2914 /* Stop all retransmit timers because we have nothing more
2916 tcp_connection_timers_reset (tc0);
2918 /* We already have a FIN but didn't transition to CLOSING
2919 * because of outstanding tx data. Close the connection. */
2920 if (tc0->flags & TCP_CONN_FINRCVD)
2922 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2923 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE,
2924 tcp_cfg.cleanup_time);
2925 session_transport_closed_notify (&tc0->connection);
2929 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2930 /* Enable waitclose because we're willing to wait for peer's
2931 * FIN but not indefinitely. */
2932 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2934 /* Don't try to deq the FIN acked */
2935 if (tc0->burst_acked > 1)
2936 session_tx_fifo_dequeue_drop (&tc0->connection,
2937 tc0->burst_acked - 1);
2938 tc0->burst_acked = 0;
2941 case TCP_STATE_FIN_WAIT_2:
2942 /* In addition to the processing for the ESTABLISHED state, if
2943 * the retransmission queue is empty, the user's CLOSE can be
2944 * acknowledged ("ok") but do not delete the TCB. */
2945 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2947 tc0->burst_acked = 0;
2949 case TCP_STATE_CLOSE_WAIT:
2950 /* Do the same processing as for the ESTABLISHED state. */
2951 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2954 if (!(tc0->flags & TCP_CONN_FINPNDG))
2957 /* Still have outstanding tx data */
2958 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2959 if (max_dequeue > tc0->burst_acked)
2963 tcp_connection_timers_reset (tc0);
2964 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2965 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2967 case TCP_STATE_CLOSING:
2968 /* In addition to the processing for the ESTABLISHED state, if
2969 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2970 * otherwise ignore the segment. */
2971 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2974 if (tc0->snd_una != tc0->snd_nxt)
2977 tcp_connection_timers_reset (tc0);
2978 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2979 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2980 session_transport_closed_notify (&tc0->connection);
2984 case TCP_STATE_LAST_ACK:
2985 /* The only thing that [should] arrive in this state is an
2986 * acknowledgment of our FIN. If our FIN is now acknowledged,
2987 * delete the TCB, enter the CLOSED state, and return. */
2989 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2992 /* Apparently our ACK for the peer's FIN was lost */
2993 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2999 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
3000 session_transport_closed_notify (&tc0->connection);
3002 /* Don't free the connection from the data path since
3003 * we can't ensure that we have no packets already enqueued
3004 * to output. Rely instead on the waitclose timer */
3005 tcp_connection_timers_reset (tc0);
3006 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
3011 case TCP_STATE_TIME_WAIT:
3012 /* The only thing that can arrive in this state is a
3013 * retransmission of the remote FIN. Acknowledge it, and restart
3014 * the 2 MSL timeout. */
3016 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3022 tcp_program_ack (tc0);
3023 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3031 /* 6: check the URG bit TODO */
3033 /* 7: process the segment text */
3036 case TCP_STATE_ESTABLISHED:
3037 case TCP_STATE_FIN_WAIT_1:
3038 case TCP_STATE_FIN_WAIT_2:
3039 if (vnet_buffer (b0)->tcp.data_len)
3040 error0 = tcp_segment_rcv (wrk, tc0, b0);
3042 case TCP_STATE_CLOSE_WAIT:
3043 case TCP_STATE_CLOSING:
3044 case TCP_STATE_LAST_ACK:
3045 case TCP_STATE_TIME_WAIT:
3046 /* This should not occur, since a FIN has been received from the
3047 * remote side. Ignore the segment text. */
3051 /* 8: check the FIN bit */
3055 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
3059 case TCP_STATE_ESTABLISHED:
3060 /* Account for the FIN and send ack */
3062 tcp_program_ack (tc0);
3063 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
3064 tcp_program_disconnect (wrk, tc0);
3065 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
3067 case TCP_STATE_SYN_RCVD:
3068 /* Send FIN-ACK, enter LAST-ACK and because the app was not
3069 * notified yet, set a cleanup timer instead of relying on
3070 * disconnect notify and the implicit close call. */
3071 tcp_connection_timers_reset (tc0);
3074 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3075 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3077 case TCP_STATE_CLOSE_WAIT:
3078 case TCP_STATE_CLOSING:
3079 case TCP_STATE_LAST_ACK:
3082 case TCP_STATE_FIN_WAIT_1:
3085 if (tc0->flags & TCP_CONN_FINPNDG)
3087 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
3088 * sending it. Since we already received a fin, do not wait
3090 tc0->flags |= TCP_CONN_FINRCVD;
3091 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3092 tcp_cfg.closewait_time);
3096 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
3097 tcp_program_ack (tc0);
3098 /* Wait for ACK for our FIN but not forever */
3099 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3100 tcp_cfg.closing_time);
3103 case TCP_STATE_FIN_WAIT_2:
3104 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
3106 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3107 tcp_connection_timers_reset (tc0);
3108 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3109 tcp_program_ack (tc0);
3110 session_transport_closed_notify (&tc0->connection);
3112 case TCP_STATE_TIME_WAIT:
3113 /* Remain in the TIME-WAIT state. Restart the time-wait
3116 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3119 error0 = TCP_ERROR_FIN_RCVD;
3123 tcp_inc_counter (rcv_process, error0, 1);
3124 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3126 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3127 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
3131 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
3133 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
3134 tcp_handle_postponed_dequeues (wrk);
3135 tcp_handle_disconnects (wrk);
3136 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3138 return from_frame->n_vectors;
3141 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
3142 vlib_node_runtime_t * node,
3143 vlib_frame_t * from_frame)
3145 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3148 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
3149 vlib_node_runtime_t * node,
3150 vlib_frame_t * from_frame)
3152 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3156 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
3158 .name = "tcp4-rcv-process",
3159 /* Takes a vector of packets. */
3160 .vector_size = sizeof (u32),
3161 .n_errors = TCP_N_ERROR,
3162 .error_strings = tcp_error_strings,
3163 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3166 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3167 foreach_tcp_state_next
3170 .format_trace = format_tcp_rx_trace_short,
3175 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3177 .name = "tcp6-rcv-process",
3178 /* Takes a vector of packets. */
3179 .vector_size = sizeof (u32),
3180 .n_errors = TCP_N_ERROR,
3181 .error_strings = tcp_error_strings,
3182 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3185 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3186 foreach_tcp_state_next
3189 .format_trace = format_tcp_rx_trace_short,
3194 * LISTEN state processing as per RFC 793 p. 65
3197 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3198 vlib_frame_t * from_frame, int is_ip4)
3200 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3201 u32 my_thread_index = vm->thread_index;
3202 tcp_connection_t *tc0;
3204 from = first_buffer = vlib_frame_vector_args (from_frame);
3205 n_left_from = from_frame->n_vectors;
3207 while (n_left_from > 0)
3212 tcp_header_t *th0 = 0;
3213 tcp_connection_t *lc0;
3216 tcp_connection_t *child0;
3217 u32 error0 = TCP_ERROR_NONE;
3223 b0 = vlib_get_buffer (vm, bi0);
3227 ip40 = vlib_buffer_get_current (b0);
3228 th0 = tcp_buffer_hdr (b0);
3232 ip60 = vlib_buffer_get_current (b0);
3233 th0 = tcp_buffer_hdr (b0);
3236 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3237 if (PREDICT_FALSE (lc0 == 0))
3239 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
3241 if (tc0->state != TCP_STATE_TIME_WAIT)
3243 error0 = TCP_ERROR_CREATE_EXISTS;
3246 lc0 = tcp_lookup_listener (b0, tc0->c_fib_index, is_ip4);
3247 /* clean up the old session */
3248 tcp_connection_del (tc0);
3251 /* Create child session. For syn-flood protection use filter */
3253 /* 1. first check for an RST: handled in dispatch */
3254 /* if (tcp_rst (th0))
3258 /* 2. second check for an ACK: handled in dispatch */
3259 /* if (tcp_ack (th0))
3261 tcp_send_reset (b0, is_ip4);
3266 /* 3. check for a SYN (did that already) */
3268 /* Make sure connection wasn't just created */
3269 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3271 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3273 error0 = TCP_ERROR_CREATE_EXISTS;
3277 /* Create child session and send SYN-ACK */
3278 child0 = tcp_connection_alloc (my_thread_index);
3279 child0->c_lcl_port = th0->dst_port;
3280 child0->c_rmt_port = th0->src_port;
3281 child0->c_is_ip4 = is_ip4;
3282 child0->state = TCP_STATE_SYN_RCVD;
3283 child0->c_fib_index = lc0->c_fib_index;
3284 child0->cc_algo = lc0->cc_algo;
3288 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3289 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3293 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3294 sizeof (ip6_address_t));
3295 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3296 sizeof (ip6_address_t));
3299 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3301 error0 = TCP_ERROR_OPTIONS;
3302 tcp_connection_free (child0);
3306 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3307 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3308 child0->rcv_las = child0->rcv_nxt;
3309 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3311 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3312 * segments are used to initialize PAWS. */
3313 if (tcp_opts_tstamp (&child0->rcv_opts))
3315 child0->tsval_recent = child0->rcv_opts.tsval;
3316 child0->tsval_recent_age = tcp_time_now ();
3319 if (tcp_opts_wscale (&child0->rcv_opts))
3320 child0->snd_wscale = child0->rcv_opts.wscale;
3322 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3323 << child0->snd_wscale;
3324 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3325 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3327 tcp_connection_init_vars (child0);
3328 child0->rto = TCP_RTO_MIN;
3330 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3331 lc0->c_thread_index, 0 /* notify */ ))
3333 tcp_connection_cleanup (child0);
3334 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3338 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3339 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3340 tcp_send_synack (child0);
3344 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3346 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3347 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3348 clib_memcpy_fast (&t0->tcp_connection, lc0,
3349 sizeof (t0->tcp_connection));
3352 n_syns += (error0 == TCP_ERROR_NONE);
3355 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3356 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3358 return from_frame->n_vectors;
3361 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3362 vlib_frame_t * from_frame)
3364 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3367 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3368 vlib_frame_t * from_frame)
3370 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3374 VLIB_REGISTER_NODE (tcp4_listen_node) =
3376 .name = "tcp4-listen",
3377 /* Takes a vector of packets. */
3378 .vector_size = sizeof (u32),
3379 .n_errors = TCP_N_ERROR,
3380 .error_strings = tcp_error_strings,
3381 .n_next_nodes = TCP_LISTEN_N_NEXT,
3384 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3385 foreach_tcp_state_next
3388 .format_trace = format_tcp_rx_trace_short,
3393 VLIB_REGISTER_NODE (tcp6_listen_node) =
3395 .name = "tcp6-listen",
3396 /* Takes a vector of packets. */
3397 .vector_size = sizeof (u32),
3398 .n_errors = TCP_N_ERROR,
3399 .error_strings = tcp_error_strings,
3400 .n_next_nodes = TCP_LISTEN_N_NEXT,
3403 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3404 foreach_tcp_state_next
3407 .format_trace = format_tcp_rx_trace_short,
3411 typedef enum _tcp_input_next
3413 TCP_INPUT_NEXT_DROP,
3414 TCP_INPUT_NEXT_LISTEN,
3415 TCP_INPUT_NEXT_RCV_PROCESS,
3416 TCP_INPUT_NEXT_SYN_SENT,
3417 TCP_INPUT_NEXT_ESTABLISHED,
3418 TCP_INPUT_NEXT_RESET,
3419 TCP_INPUT_NEXT_PUNT,
3423 #define foreach_tcp4_input_next \
3424 _ (DROP, "ip4-drop") \
3425 _ (LISTEN, "tcp4-listen") \
3426 _ (RCV_PROCESS, "tcp4-rcv-process") \
3427 _ (SYN_SENT, "tcp4-syn-sent") \
3428 _ (ESTABLISHED, "tcp4-established") \
3429 _ (RESET, "tcp4-reset") \
3430 _ (PUNT, "ip4-punt")
3432 #define foreach_tcp6_input_next \
3433 _ (DROP, "ip6-drop") \
3434 _ (LISTEN, "tcp6-listen") \
3435 _ (RCV_PROCESS, "tcp6-rcv-process") \
3436 _ (SYN_SENT, "tcp6-syn-sent") \
3437 _ (ESTABLISHED, "tcp6-established") \
3438 _ (RESET, "tcp6-reset") \
3439 _ (PUNT, "ip6-punt")
3441 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3444 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3445 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3447 tcp_connection_t *tc;
3452 for (i = 0; i < n_bufs; i++)
3454 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3456 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3457 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3459 tcp = vlib_buffer_get_current (bs[i]);
3460 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3466 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3468 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3470 *next = TCP_INPUT_NEXT_DROP;
3472 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3474 *next = TCP_INPUT_NEXT_PUNT;
3475 *error = TCP_ERROR_PUNT;
3479 *next = TCP_INPUT_NEXT_RESET;
3480 *error = TCP_ERROR_NO_LISTENER;
3484 always_inline tcp_connection_t *
3485 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3486 u8 is_ip4, u8 is_nolookup)
3488 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3489 int n_advance_bytes, n_data_bytes;
3490 transport_connection_t *tc;
3496 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3497 int ip_hdr_bytes = ip4_header_bytes (ip4);
3498 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3500 *error = TCP_ERROR_LENGTH;
3503 tcp = ip4_next_header (ip4);
3504 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3505 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3506 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3508 /* Length check. Checksum computed by ipx_local no need to compute again */
3509 if (PREDICT_FALSE (n_data_bytes < 0))
3511 *error = TCP_ERROR_LENGTH;
3516 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3517 &ip4->src_address, tcp->dst_port,
3519 TRANSPORT_PROTO_TCP, thread_index,
3524 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3525 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3527 *error = TCP_ERROR_LENGTH;
3530 tcp = ip6_next_header (ip6);
3531 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3532 n_advance_bytes = tcp_header_bytes (tcp);
3533 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3535 n_advance_bytes += sizeof (ip6[0]);
3537 if (PREDICT_FALSE (n_data_bytes < 0))
3539 *error = TCP_ERROR_LENGTH;
3546 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3548 ip4_main_t *im = &ip4_main;
3549 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3550 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3553 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3555 tcp->dst_port, tcp->src_port,
3556 TRANSPORT_PROTO_TCP,
3557 thread_index, &result);
3563 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3564 tcp.connection_index,
3567 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3568 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3569 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3570 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3571 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3573 vnet_buffer (b)->tcp.flags = 0;
3575 *error = result ? TCP_ERROR_NONE + result : *error;
3577 return tcp_get_connection_from_transport (tc);
3581 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3582 vlib_buffer_t * b, u16 * next, u32 * error)
3587 tcp = tcp_buffer_hdr (b);
3588 flags = tcp->flags & filter_flags;
3589 *next = tm->dispatch_table[tc->state][flags].next;
3590 *error = tm->dispatch_table[tc->state][flags].error;
3593 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3594 || *next == TCP_INPUT_NEXT_RESET))
3596 /* Overload tcp flags to store state */
3597 tcp_state_t state = tc->state;
3598 vnet_buffer (b)->tcp.flags = tc->state;
3600 if (*error == TCP_ERROR_DISPATCH)
3601 clib_warning ("tcp conn %u disp error state %U flags %U",
3602 tc->c_c_index, format_tcp_state, state,
3603 format_tcp_flags, (int) flags);
3608 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3609 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3611 u32 n_left_from, *from, thread_index = vm->thread_index;
3612 tcp_main_t *tm = vnet_get_tcp_main ();
3613 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3614 u16 nexts[VLIB_FRAME_SIZE], *next;
3616 tcp_set_time_now (tcp_get_worker (thread_index));
3618 from = vlib_frame_vector_args (frame);
3619 n_left_from = frame->n_vectors;
3620 vlib_get_buffers (vm, from, bufs, n_left_from);
3625 while (n_left_from >= 4)
3627 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3628 tcp_connection_t *tc0, *tc1;
3631 vlib_prefetch_buffer_header (b[2], STORE);
3632 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3634 vlib_prefetch_buffer_header (b[3], STORE);
3635 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3638 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3640 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3642 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3645 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3647 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3648 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3650 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3651 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3653 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3654 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3658 if (PREDICT_TRUE (tc0 != 0))
3660 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3661 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3662 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3665 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3667 if (PREDICT_TRUE (tc1 != 0))
3669 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3670 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3671 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3674 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3681 while (n_left_from > 0)
3683 tcp_connection_t *tc0;
3684 u32 error0 = TCP_ERROR_NO_LISTENER;
3686 if (n_left_from > 1)
3688 vlib_prefetch_buffer_header (b[1], STORE);
3689 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3692 next[0] = TCP_INPUT_NEXT_DROP;
3693 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3695 if (PREDICT_TRUE (tc0 != 0))
3697 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3698 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3699 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3702 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3709 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3710 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3712 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3713 return frame->n_vectors;
3716 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3717 vlib_node_runtime_t * node,
3718 vlib_frame_t * from_frame)
3720 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3721 1 /* is_nolookup */ );
3724 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3725 vlib_node_runtime_t * node,
3726 vlib_frame_t * from_frame)
3728 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3729 1 /* is_nolookup */ );
3733 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3735 .name = "tcp4-input-nolookup",
3736 /* Takes a vector of packets. */
3737 .vector_size = sizeof (u32),
3738 .n_errors = TCP_N_ERROR,
3739 .error_strings = tcp_error_strings,
3740 .n_next_nodes = TCP_INPUT_N_NEXT,
3743 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3744 foreach_tcp4_input_next
3747 .format_buffer = format_tcp_header,
3748 .format_trace = format_tcp_rx_trace,
3753 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3755 .name = "tcp6-input-nolookup",
3756 /* Takes a vector of packets. */
3757 .vector_size = sizeof (u32),
3758 .n_errors = TCP_N_ERROR,
3759 .error_strings = tcp_error_strings,
3760 .n_next_nodes = TCP_INPUT_N_NEXT,
3763 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3764 foreach_tcp6_input_next
3767 .format_buffer = format_tcp_header,
3768 .format_trace = format_tcp_rx_trace,
3772 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3773 vlib_frame_t * from_frame)
3775 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3776 0 /* is_nolookup */ );
3779 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3780 vlib_frame_t * from_frame)
3782 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3783 0 /* is_nolookup */ );
3787 VLIB_REGISTER_NODE (tcp4_input_node) =
3789 .name = "tcp4-input",
3790 /* Takes a vector of packets. */
3791 .vector_size = sizeof (u32),
3792 .n_errors = TCP_N_ERROR,
3793 .error_strings = tcp_error_strings,
3794 .n_next_nodes = TCP_INPUT_N_NEXT,
3797 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3798 foreach_tcp4_input_next
3801 .format_buffer = format_tcp_header,
3802 .format_trace = format_tcp_rx_trace,
3807 VLIB_REGISTER_NODE (tcp6_input_node) =
3809 .name = "tcp6-input",
3810 /* Takes a vector of packets. */
3811 .vector_size = sizeof (u32),
3812 .n_errors = TCP_N_ERROR,
3813 .error_strings = tcp_error_strings,
3814 .n_next_nodes = TCP_INPUT_N_NEXT,
3817 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3818 foreach_tcp6_input_next
3821 .format_buffer = format_tcp_header,
3822 .format_trace = format_tcp_rx_trace,
3826 #ifndef CLIB_MARCH_VARIANT
3828 tcp_dispatch_table_init (tcp_main_t * tm)
3831 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3832 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3834 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3835 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3838 #define _(t,f,n,e) \
3840 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3841 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3844 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3845 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3846 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3847 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3848 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3849 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3850 TCP_ERROR_ACK_INVALID);
3851 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3852 TCP_ERROR_SEGMENT_INVALID);
3853 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3854 TCP_ERROR_SEGMENT_INVALID);
3855 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3856 TCP_ERROR_INVALID_CONNECTION);
3857 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3858 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3859 TCP_ERROR_SEGMENT_INVALID);
3860 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3861 TCP_ERROR_SEGMENT_INVALID);
3862 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3864 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3865 TCP_ERROR_SEGMENT_INVALID);
3866 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3867 TCP_ERROR_SEGMENT_INVALID);
3868 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3869 TCP_ERROR_SEGMENT_INVALID);
3870 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3871 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3872 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3873 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3874 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3875 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3877 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3878 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3880 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3882 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3883 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3884 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3885 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3887 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3889 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3890 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3891 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3893 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3894 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3895 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3896 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3897 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3898 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3899 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3900 /* SYN-ACK for a SYN */
3901 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3903 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3904 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3905 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3907 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3908 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3910 /* ACK for for established connection -> tcp-established. */
3911 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3912 /* FIN for for established connection -> tcp-established. */
3913 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3914 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3916 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3918 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3919 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3920 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3922 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3923 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3924 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3925 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3926 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3927 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3928 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3929 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3931 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3932 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3934 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3936 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3937 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3938 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3939 /* ACK or FIN-ACK to our FIN */
3940 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3941 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3943 /* FIN in reply to our FIN from the other side */
3944 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3945 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3946 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3948 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3949 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3950 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3951 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3952 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3953 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3954 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3956 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3957 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3958 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3959 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3961 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3963 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3964 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3965 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3966 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3968 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3969 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3970 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3971 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3973 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3975 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3976 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3977 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3978 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3980 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3981 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3983 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3985 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3986 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3987 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3989 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3990 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3991 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3992 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3993 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3994 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3995 /* FIN confirming that the peer (app) has closed */
3996 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3997 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3998 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4000 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4001 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4003 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4004 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4006 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4007 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4009 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4010 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4011 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4012 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4014 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4016 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4017 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4018 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4020 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4021 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4022 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4023 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4024 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4025 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4026 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4027 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4029 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4030 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4032 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4034 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4035 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4036 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
4037 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4038 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4040 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4041 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4043 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4044 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
4045 * incoming segment not containing a RST causes a RST to be sent in
4047 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
4048 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
4049 TCP_ERROR_CONNECTION_CLOSED);
4050 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
4051 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
4052 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
4057 static clib_error_t *
4058 tcp_input_init (vlib_main_t * vm)
4060 clib_error_t *error = 0;
4061 tcp_main_t *tm = vnet_get_tcp_main ();
4063 if ((error = vlib_call_init_function (vm, tcp_init)))
4066 /* Initialize dispatch table. */
4067 tcp_dispatch_table_init (tm);
4072 VLIB_INIT_FUNCTION (tcp_input_init);
4074 #endif /* CLIB_MARCH_VARIANT */
4077 * fd.io coding-style-patch-verification: ON
4080 * eval: (c-set-style "gnu")