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 <vnet/tcp/tcp.h>
19 typedef enum _tcp_output_next
22 TCP_OUTPUT_NEXT_IP_LOOKUP,
23 TCP_OUTPUT_NEXT_IP_REWRITE,
24 TCP_OUTPUT_NEXT_IP_ARP,
28 #define foreach_tcp4_output_next \
29 _ (DROP, "error-drop") \
30 _ (IP_LOOKUP, "ip4-lookup") \
31 _ (IP_REWRITE, "ip4-rewrite") \
34 #define foreach_tcp6_output_next \
35 _ (DROP, "error-drop") \
36 _ (IP_LOOKUP, "ip6-lookup") \
37 _ (IP_REWRITE, "ip6-rewrite") \
38 _ (IP_ARP, "ip6-discover-neighbor")
40 static char *tcp_error_strings[] = {
41 #define tcp_error(n,s) s,
42 #include <vnet/tcp/tcp_error.def>
48 tcp_header_t tcp_header;
49 tcp_connection_t tcp_connection;
53 format_tcp_tx_trace (u8 * s, va_list * args)
55 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
56 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
57 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
58 u32 indent = format_get_indent (s);
60 s = format (s, "%U\n%U%U",
61 format_tcp_header, &t->tcp_header, 128,
62 format_white_space, indent,
63 format_tcp_connection, &t->tcp_connection, 1);
68 #ifndef CLIB_MARCH_VARIANT
70 tcp_window_compute_scale (u32 window)
73 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
79 * Update max segment size we're able to process.
81 * The value is constrained by our interface's MTU and IP options. It is
82 * also what we advertise to our peer.
85 tcp_update_rcv_mss (tcp_connection_t * tc)
87 /* TODO find our iface MTU */
88 tc->mss = tcp_cfg.default_mtu - sizeof (tcp_header_t);
92 * TCP's initial window
95 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
97 /* RFC 6928 recommends the value lower. However at the time our connections
98 * are initialized, fifos may not be allocated. Therefore, advertise the
99 * smallest possible unscaled window size and update once fifos are
100 * assigned to the session.
103 tcp_update_rcv_mss (tc);
104 TCP_IW_N_SEGMENTS * tc->mss;
106 return tcp_cfg.min_rx_fifo;
110 * Compute initial window and scale factor. As per RFC1323, window field in
111 * SYN and SYN-ACK segments is never scaled.
114 tcp_initial_window_to_advertise (tcp_connection_t * tc)
116 /* Compute rcv wscale only if peer advertised support for it */
117 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
118 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
120 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
122 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
126 tcp_update_rcv_wnd (tcp_connection_t * tc)
128 u32 available_space, wnd;
131 ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection));
134 * Figure out how much space we have available
136 available_space = transport_max_rx_enqueue (&tc->connection);
137 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
141 * Use the above and what we know about what we've previously advertised
142 * to compute the new window
144 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
146 /* Bad. Thou shalt not shrink */
147 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
149 wnd = clib_max (observed_wnd, 0);
150 TCP_EVT_DBG (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
154 wnd = available_space;
157 /* Make sure we have a multiple of rcv_wscale */
158 if (wnd && tc->rcv_wscale)
160 wnd &= ~((1 << tc->rcv_wscale) - 1);
162 wnd = 1 << tc->rcv_wscale;
165 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
169 * Compute and return window to advertise, scaled as per RFC1323
172 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
174 if (state < TCP_STATE_ESTABLISHED)
175 return tcp_initial_window_to_advertise (tc);
177 tcp_update_rcv_wnd (tc);
178 return tc->rcv_wnd >> tc->rcv_wscale;
182 * Write TCP options to segment.
185 tcp_options_write (u8 * data, tcp_options_t * opts)
188 u32 buf, seq_len = 4;
190 if (tcp_opts_mss (opts))
192 *data++ = TCP_OPTION_MSS;
193 *data++ = TCP_OPTION_LEN_MSS;
194 buf = clib_host_to_net_u16 (opts->mss);
195 clib_memcpy_fast (data, &buf, sizeof (opts->mss));
196 data += sizeof (opts->mss);
197 opts_len += TCP_OPTION_LEN_MSS;
200 if (tcp_opts_wscale (opts))
202 *data++ = TCP_OPTION_WINDOW_SCALE;
203 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
204 *data++ = opts->wscale;
205 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
208 if (tcp_opts_sack_permitted (opts))
210 *data++ = TCP_OPTION_SACK_PERMITTED;
211 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
212 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
215 if (tcp_opts_tstamp (opts))
217 *data++ = TCP_OPTION_TIMESTAMP;
218 *data++ = TCP_OPTION_LEN_TIMESTAMP;
219 buf = clib_host_to_net_u32 (opts->tsval);
220 clib_memcpy_fast (data, &buf, sizeof (opts->tsval));
221 data += sizeof (opts->tsval);
222 buf = clib_host_to_net_u32 (opts->tsecr);
223 clib_memcpy_fast (data, &buf, sizeof (opts->tsecr));
224 data += sizeof (opts->tsecr);
225 opts_len += TCP_OPTION_LEN_TIMESTAMP;
228 if (tcp_opts_sack (opts))
232 if (opts->n_sack_blocks != 0)
234 *data++ = TCP_OPTION_SACK_BLOCK;
235 *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
236 for (i = 0; i < opts->n_sack_blocks; i++)
238 buf = clib_host_to_net_u32 (opts->sacks[i].start);
239 clib_memcpy_fast (data, &buf, seq_len);
241 buf = clib_host_to_net_u32 (opts->sacks[i].end);
242 clib_memcpy_fast (data, &buf, seq_len);
245 opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
249 /* Terminate TCP options */
252 *data++ = TCP_OPTION_EOL;
253 opts_len += TCP_OPTION_LEN_EOL;
256 /* Pad with zeroes to a u32 boundary */
259 *data++ = TCP_OPTION_NOOP;
260 opts_len += TCP_OPTION_LEN_NOOP;
266 tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale)
270 opts->flags |= TCP_OPTS_FLAG_MSS;
271 opts->mss = tcp_cfg.default_mtu; /*XXX discover that */
272 len += TCP_OPTION_LEN_MSS;
274 opts->flags |= TCP_OPTS_FLAG_WSCALE;
275 opts->wscale = wnd_scale;
276 len += TCP_OPTION_LEN_WINDOW_SCALE;
278 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
279 opts->tsval = tcp_time_now ();
281 len += TCP_OPTION_LEN_TIMESTAMP;
285 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
286 len += TCP_OPTION_LEN_SACK_PERMITTED;
289 /* Align to needed boundary */
290 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
295 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
299 opts->flags |= TCP_OPTS_FLAG_MSS;
301 len += TCP_OPTION_LEN_MSS;
303 if (tcp_opts_wscale (&tc->rcv_opts))
305 opts->flags |= TCP_OPTS_FLAG_WSCALE;
306 opts->wscale = tc->rcv_wscale;
307 len += TCP_OPTION_LEN_WINDOW_SCALE;
310 if (tcp_opts_tstamp (&tc->rcv_opts))
312 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
313 opts->tsval = tcp_time_now ();
314 opts->tsecr = tc->tsval_recent;
315 len += TCP_OPTION_LEN_TIMESTAMP;
318 if (tcp_opts_sack_permitted (&tc->rcv_opts))
320 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
321 len += TCP_OPTION_LEN_SACK_PERMITTED;
324 /* Align to needed boundary */
325 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
330 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
336 if (tcp_opts_tstamp (&tc->rcv_opts))
338 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
339 opts->tsval = tcp_tstamp (tc);
340 opts->tsecr = tc->tsval_recent;
341 len += TCP_OPTION_LEN_TIMESTAMP;
343 if (tcp_opts_sack_permitted (&tc->rcv_opts))
345 if (vec_len (tc->snd_sacks))
347 opts->flags |= TCP_OPTS_FLAG_SACK;
348 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
349 tc->snd_sack_pos = 0;
350 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
351 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
352 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
353 TCP_OPTS_MAX_SACK_BLOCKS);
354 tc->snd_sack_pos += opts->n_sack_blocks;
355 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
359 /* Align to needed boundary */
360 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
365 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
370 case TCP_STATE_ESTABLISHED:
371 case TCP_STATE_CLOSE_WAIT:
372 case TCP_STATE_FIN_WAIT_1:
373 case TCP_STATE_LAST_ACK:
374 case TCP_STATE_CLOSING:
375 case TCP_STATE_FIN_WAIT_2:
376 case TCP_STATE_TIME_WAIT:
377 case TCP_STATE_CLOSED:
378 return tcp_make_established_options (tc, opts);
379 case TCP_STATE_SYN_RCVD:
380 return tcp_make_synack_options (tc, opts);
381 case TCP_STATE_SYN_SENT:
382 return tcp_make_syn_options (opts, tc->rcv_wscale);
384 clib_warning ("State not handled! %d", state);
390 * Update burst send vars
392 * - Updates snd_mss to reflect the effective segment size that we can send
393 * by taking into account all TCP options, including SACKs.
394 * - Cache 'on the wire' options for reuse
395 * - Updates receive window which can be reused for a burst.
397 * This should *only* be called when doing bursts
400 tcp_update_burst_snd_vars (tcp_connection_t * tc)
402 tcp_main_t *tm = &tcp_main;
404 /* Compute options to be used for connection. These may be reused when
405 * sending data or to compute the effective mss (snd_mss) */
406 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
407 TCP_STATE_ESTABLISHED);
409 /* XXX check if MTU has been updated */
410 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
411 ASSERT (tc->snd_mss > 0);
413 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
416 tcp_update_rcv_wnd (tc);
418 if (tc->flags & TCP_CONN_RATE_SAMPLE)
419 tc->flags |= TCP_CONN_TRACK_BURST;
421 if (tc->snd_una == tc->snd_nxt)
422 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
426 tcp_init_mss (tcp_connection_t * tc)
428 u16 default_min_mss = 536;
429 tcp_update_rcv_mss (tc);
431 /* TODO cache mss and consider PMTU discovery */
432 tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss);
434 if (tc->snd_mss < 45)
436 /* Assume that at least the min default mss works */
437 tc->snd_mss = default_min_mss;
438 tc->rcv_opts.mss = default_min_mss;
441 /* We should have enough space for 40 bytes of options */
442 ASSERT (tc->snd_mss > 45);
444 /* If we use timestamp option, account for it */
445 if (tcp_opts_tstamp (&tc->rcv_opts))
446 tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP;
448 #endif /* CLIB_MARCH_VARIANT */
451 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
453 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
454 vlib_buffer_free_one (vm, b->next_buffer);
455 /* Zero all flags but free list index and trace flag */
456 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
458 b->current_length = 0;
459 b->total_length_not_including_first_buffer = 0;
460 vnet_buffer (b)->tcp.flags = 0;
462 /* Leave enough space for headers */
463 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
466 #ifndef CLIB_MARCH_VARIANT
468 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
470 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
471 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
472 b->total_length_not_including_first_buffer = 0;
474 vnet_buffer (b)->tcp.flags = 0;
475 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
476 /* Leave enough space for headers */
477 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
484 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
487 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
488 u8 tcp_opts_len, tcp_hdr_opts_len;
492 wnd = tcp_window_to_advertise (tc, state);
494 /* Make and write options */
495 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
496 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
498 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
499 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
501 tcp_options_write ((u8 *) (th + 1), snd_opts);
502 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
505 tcp_zero_rwnd_sent_on (tc);
507 tcp_zero_rwnd_sent_off (tc);
511 * Convert buffer to ACK
514 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
516 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
517 TCP_EVT_DBG (TCP_EVT_ACK_SENT, tc);
518 tc->rcv_las = tc->rcv_nxt;
522 * Convert buffer to FIN-ACK
525 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
527 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
531 * Convert buffer to SYN
534 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
536 u8 tcp_hdr_opts_len, tcp_opts_len;
539 tcp_options_t snd_opts;
541 initial_wnd = tcp_initial_window_to_advertise (tc);
543 /* Make and write options */
544 clib_memset (&snd_opts, 0, sizeof (snd_opts));
545 tcp_opts_len = tcp_make_syn_options (&snd_opts, tc->rcv_wscale);
546 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
548 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
549 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
551 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
552 tcp_options_write ((u8 *) (th + 1), &snd_opts);
556 * Convert buffer to SYN-ACK
559 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
561 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
562 u8 tcp_opts_len, tcp_hdr_opts_len;
566 clib_memset (snd_opts, 0, sizeof (*snd_opts));
567 initial_wnd = tcp_initial_window_to_advertise (tc);
568 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
569 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
571 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
572 tc->rcv_nxt, tcp_hdr_opts_len,
573 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
574 tcp_options_write ((u8 *) (th + 1), snd_opts);
576 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
580 tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
581 u8 is_ip4, u32 fib_index, u8 flush)
583 vlib_main_t *vm = wrk->vm;
584 u32 *to_next, next_index;
587 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
590 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
591 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
593 /* Send to IP lookup */
594 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
595 tcp_trajectory_add_start (b, 1);
597 f = wrk->ip_lookup_tx_frames[!is_ip4];
600 f = vlib_get_frame_to_node (vm, next_index);
602 wrk->ip_lookup_tx_frames[!is_ip4] = f;
605 to_next = vlib_frame_vector_args (f);
606 to_next[f->n_vectors] = bi;
608 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
610 vlib_put_frame_to_node (vm, next_index, f);
611 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
616 tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b,
617 u32 bi, u8 is_ip4, u32 fib_index)
619 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1);
623 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
624 u8 is_ip4, u32 fib_index)
626 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0);
627 if (wrk->vm->thread_index == 0 && vlib_num_workers ())
628 session_flush_frames_main_thread (wrk->vm);
632 tcp_enqueue_to_output_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
635 u32 *to_next, next_index;
638 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
641 /* Decide where to send the packet */
642 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
643 tcp_trajectory_add_start (b, 2);
645 /* Get frame to v4/6 output node */
646 f = wrk->tx_frames[!is_ip4];
649 f = vlib_get_frame_to_node (wrk->vm, next_index);
651 wrk->tx_frames[!is_ip4] = f;
653 to_next = vlib_frame_vector_args (f);
654 to_next[f->n_vectors] = bi;
656 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
658 vlib_put_frame_to_node (wrk->vm, next_index, f);
659 wrk->tx_frames[!is_ip4] = 0;
664 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
667 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 0);
671 tcp_enqueue_to_output_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
674 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 1);
676 #endif /* CLIB_MARCH_VARIANT */
679 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
680 tcp_state_t state, u8 thread_index, u8 is_ip4)
685 ip4_address_t src_ip40, dst_ip40;
686 ip6_address_t src_ip60, dst_ip60;
687 u16 src_port, dst_port;
692 /* Find IP and TCP headers */
693 th0 = tcp_buffer_hdr (b0);
695 /* Save src and dst ip */
698 ih4 = vlib_buffer_get_current (b0);
699 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
700 src_ip40.as_u32 = ih4->src_address.as_u32;
701 dst_ip40.as_u32 = ih4->dst_address.as_u32;
705 ih6 = vlib_buffer_get_current (b0);
706 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
707 clib_memcpy_fast (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
708 clib_memcpy_fast (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
711 src_port = th0->src_port;
712 dst_port = th0->dst_port;
714 /* Try to determine what/why we're actually resetting */
715 if (state == TCP_STATE_CLOSED)
720 tmp = clib_net_to_host_u32 (th0->seq_number);
722 /* Got a SYN for no listener. */
723 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
724 ack = clib_host_to_net_u32 (tmp + 1);
729 flags = TCP_FLAG_RST;
730 seq = th0->ack_number;
734 tcp_reuse_buffer (vm, b0);
735 tcp_trajectory_add_start (b0, 4);
736 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
737 sizeof (tcp_header_t), flags, 0);
741 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
743 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
748 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
750 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
757 #ifndef CLIB_MARCH_VARIANT
759 * Send reset without reusing existing buffer
761 * It extracts connection info out of original packet
764 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
765 u32 thread_index, u8 is_ip4)
767 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
768 vlib_main_t *vm = wrk->vm;
770 u32 bi, sw_if_index, fib_index;
771 u8 tcp_hdr_len, flags = 0;
772 tcp_header_t *th, *pkt_th;
774 ip4_header_t *ih4, *pkt_ih4;
775 ip6_header_t *ih6, *pkt_ih6;
776 fib_protocol_t fib_proto;
778 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
781 b = vlib_get_buffer (vm, bi);
782 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
783 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
784 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
785 tcp_init_buffer (vm, b);
787 /* Make and write options */
788 tcp_hdr_len = sizeof (tcp_header_t);
792 pkt_ih4 = vlib_buffer_get_current (pkt);
793 pkt_th = ip4_next_header (pkt_ih4);
797 pkt_ih6 = vlib_buffer_get_current (pkt);
798 pkt_th = ip6_next_header (pkt_ih6);
801 if (tcp_ack (pkt_th))
803 flags = TCP_FLAG_RST;
804 seq = pkt_th->ack_number;
805 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
809 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
811 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
814 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
815 seq, ack, tcp_hdr_len, flags, 0);
817 /* Swap src and dst ip */
820 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
821 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
822 &pkt_ih4->src_address, IP_PROTOCOL_TCP, 1);
823 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
828 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
830 ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
831 &pkt_ih6->src_address, IP_PROTOCOL_TCP);
832 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
836 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index);
837 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
838 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
839 TCP_ERROR_RST_SENT, 1);
843 * Build and set reset packet for connection
846 tcp_send_reset (tcp_connection_t * tc)
848 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
849 vlib_main_t *vm = wrk->vm;
853 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
856 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
858 b = vlib_get_buffer (vm, bi);
859 tcp_init_buffer (vm, b);
861 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
862 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
863 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
864 flags = TCP_FLAG_RST;
865 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
866 tc->rcv_nxt, tcp_hdr_opts_len, flags,
868 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
869 ASSERT (opts_write_len == tc->snd_opts_len);
870 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
874 ih4 = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip.ip4,
875 &tc->c_rmt_ip.ip4, IP_PROTOCOL_TCP, 0);
876 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
882 ih6 = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip.ip6,
883 &tc->c_rmt_ip.ip6, IP_PROTOCOL_TCP);
884 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
887 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
888 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
889 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
890 TCP_ERROR_RST_SENT, 1);
894 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
897 tcp_header_t *th = vlib_buffer_get_current (b);
898 vlib_main_t *vm = wrk->vm;
902 ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
903 &tc->c_rmt_ip4, IP_PROTOCOL_TCP, 1);
904 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
911 ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
912 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
913 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
921 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
922 * The packet is not forwarded through tcpx_output to avoid doing lookups
923 * in the half_open pool.
926 tcp_send_syn (tcp_connection_t * tc)
928 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
929 vlib_main_t *vm = wrk->vm;
934 * Setup retransmit and establish timers before requesting buffer
935 * such that we can return if we've ran out.
937 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
938 tc->rto * TCP_TO_TIMER_TICK);
940 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
942 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
946 b = vlib_get_buffer (vm, bi);
947 tcp_init_buffer (vm, b);
948 tcp_make_syn (tc, b);
950 /* Measure RTT with this */
951 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
952 tc->rtt_seq = tc->snd_nxt;
955 tcp_push_ip_hdr (wrk, tc, b);
956 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
957 TCP_EVT_DBG (TCP_EVT_SYN_SENT, tc);
961 tcp_send_synack (tcp_connection_t * tc)
963 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
964 vlib_main_t *vm = wrk->vm;
968 tcp_retransmit_timer_force_update (tc);
970 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
972 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
976 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
977 b = vlib_get_buffer (vm, bi);
978 tcp_init_buffer (vm, b);
979 tcp_make_synack (tc, b);
980 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
981 TCP_EVT_DBG (TCP_EVT_SYNACK_SENT, tc);
985 * Flush tx frame populated by retransmits and timer pops
988 tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4)
990 if (wrk->tx_frames[!is_ip4])
993 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
994 vlib_put_frame_to_node (wrk->vm, next_index, wrk->tx_frames[!is_ip4]);
995 wrk->tx_frames[!is_ip4] = 0;
1000 * Flush ip lookup tx frames populated by timer pops
1003 tcp_flush_frame_to_ip_lookup (tcp_worker_ctx_t * wrk, u8 is_ip4)
1005 if (wrk->ip_lookup_tx_frames[!is_ip4])
1008 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
1009 vlib_put_frame_to_node (wrk->vm, next_index,
1010 wrk->ip_lookup_tx_frames[!is_ip4]);
1011 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
1016 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
1019 tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk)
1021 tcp_flush_frame_to_output (wrk, 1);
1022 tcp_flush_frame_to_output (wrk, 0);
1023 tcp_flush_frame_to_ip_lookup (wrk, 1);
1024 tcp_flush_frame_to_ip_lookup (wrk, 0);
1031 tcp_send_fin (tcp_connection_t * tc)
1033 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1034 vlib_main_t *vm = wrk->vm;
1039 fin_snt = tc->flags & TCP_CONN_FINSNT;
1043 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1045 /* Out of buffers so program fin retransmit ASAP */
1046 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1050 /* Make sure retransmit retries a fin not data */
1051 tc->flags |= TCP_CONN_FINSNT;
1055 tcp_retransmit_timer_force_update (tc);
1056 b = vlib_get_buffer (vm, bi);
1057 tcp_init_buffer (vm, b);
1058 tcp_make_fin (tc, b);
1059 tcp_enqueue_to_output_now (wrk, b, bi, tc->c_is_ip4);
1060 TCP_EVT_DBG (TCP_EVT_FIN_SENT, tc);
1061 /* Account for the FIN */
1065 tc->flags |= TCP_CONN_FINSNT;
1066 tc->flags &= ~TCP_CONN_FINPNDG;
1067 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
1072 * Push TCP header and update connection variables. Should only be called
1073 * for segments with data, not for 'control' packets.
1076 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
1077 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
1079 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
1080 u32 advertise_wnd, data_len;
1081 tcp_main_t *tm = &tcp_main;
1084 data_len = b->current_length;
1085 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1086 data_len += b->total_length_not_including_first_buffer;
1088 vnet_buffer (b)->tcp.flags = 0;
1089 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
1092 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1094 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
1097 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1099 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
1101 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
1103 if (seq_geq (tc->psh_seq, snd_nxt)
1104 && seq_lt (tc->psh_seq, snd_nxt + data_len))
1105 flags |= TCP_FLAG_PSH;
1107 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
1108 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1113 clib_memcpy_fast ((u8 *) (th + 1),
1114 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1119 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1120 ASSERT (len == tc->snd_opts_len);
1124 * Update connection variables
1128 tc->snd_nxt += data_len;
1129 tc->rcv_las = tc->rcv_nxt;
1131 tc->bytes_out += data_len;
1132 tc->data_segs_out += 1;
1134 TCP_EVT_DBG (TCP_EVT_PKTIZE, tc);
1138 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
1140 tcp_connection_t *tc = (tcp_connection_t *) tconn;
1142 if (tc->flags & TCP_CONN_TRACK_BURST)
1144 tcp_bt_check_app_limited (tc);
1145 tcp_bt_track_tx (tc);
1146 tc->flags &= ~TCP_CONN_TRACK_BURST;
1149 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1150 /* update_snd_nxt */ 1);
1152 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1153 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1154 /* If not tracking an ACK, start tracking */
1155 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1157 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1158 tc->rtt_seq = tc->snd_nxt;
1160 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1162 tcp_retransmit_timer_set (tc);
1165 tcp_trajectory_add_start (b, 3);
1170 tcp_send_ack (tcp_connection_t * tc)
1172 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1173 vlib_main_t *vm = wrk->vm;
1177 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1179 tcp_update_rcv_wnd (tc);
1182 b = vlib_get_buffer (vm, bi);
1183 tcp_init_buffer (vm, b);
1184 tcp_make_ack (tc, b);
1185 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1189 tcp_program_ack (tcp_connection_t * tc)
1191 if (!(tc->flags & TCP_CONN_SNDACK))
1193 session_add_self_custom_tx_evt (&tc->connection, 1);
1194 tc->flags |= TCP_CONN_SNDACK;
1199 tcp_program_dupack (tcp_connection_t * tc)
1201 if (!(tc->flags & TCP_CONN_SNDACK))
1203 session_add_self_custom_tx_evt (&tc->connection, 1);
1204 tc->flags |= TCP_CONN_SNDACK;
1206 if (tc->pending_dupacks < 255)
1207 tc->pending_dupacks += 1;
1211 tcp_program_fastretransmit (tcp_connection_t * tc)
1213 if (!(tc->flags & TCP_CONN_FRXT_PENDING))
1215 session_add_self_custom_tx_evt (&tc->connection, 0);
1216 tc->flags |= TCP_CONN_FRXT_PENDING;
1221 * Delayed ack timer handler
1223 * Sends delayed ACK when timer expires
1226 tcp_timer_delack_handler (u32 index)
1228 u32 thread_index = vlib_get_thread_index ();
1229 tcp_connection_t *tc;
1231 tc = tcp_connection_get (index, thread_index);
1232 tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID;
1237 * Send Window Update ACK,
1238 * ensuring that it will be sent once, if RWND became non-zero,
1239 * after zero RWND has been advertised in ACK before
1242 tcp_send_window_update_ack (tcp_connection_t * tc)
1246 if (tcp_zero_rwnd_sent (tc))
1248 win = tcp_window_to_advertise (tc, tc->state);
1251 tcp_zero_rwnd_sent_off (tc);
1252 tcp_program_ack (tc);
1258 * Allocate a new buffer and build a new tcp segment
1260 * @param wrk tcp worker
1261 * @param tc connection for which the segment will be allocated
1262 * @param offset offset of the first byte in the tx fifo
1263 * @param max_deq_byte segment size
1264 * @param[out] b pointer to buffer allocated
1266 * @return the number of bytes in the segment or 0 if buffer cannot be
1267 * allocated or no data available
1270 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1271 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1273 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1274 vlib_main_t *vm = wrk->vm;
1279 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1284 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1287 * Allocate and fill in buffer(s)
1290 /* Easy case, buffer size greater than mss */
1291 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1293 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1295 *b = vlib_get_buffer (vm, bi);
1296 data = tcp_init_buffer (vm, *b);
1297 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1299 ASSERT (n_bytes == max_deq_bytes);
1300 b[0]->current_length = n_bytes;
1301 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1302 /* burst */ 0, /* update_snd_nxt */ 0);
1304 /* Split mss into multiple buffers */
1307 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1308 u16 n_peeked, len_to_deq;
1309 vlib_buffer_t *chain_b, *prev_b;
1312 /* Make sure we have enough buffers */
1313 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1314 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1315 CLIB_CACHE_LINE_BYTES);
1316 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1317 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1320 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1324 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1325 data = tcp_init_buffer (vm, *b);
1326 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1328 TRANSPORT_MAX_HDRS_LEN);
1329 b[0]->current_length = n_bytes;
1330 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1331 b[0]->total_length_not_including_first_buffer = 0;
1332 max_deq_bytes -= n_bytes;
1335 for (i = 1; i < n_bufs_per_seg; i++)
1338 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1339 chain_bi = wrk->tx_buffers[--n_bufs];
1340 chain_b = vlib_get_buffer (vm, chain_bi);
1341 chain_b->current_data = 0;
1342 data = vlib_buffer_get_current (chain_b);
1343 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1346 ASSERT (n_peeked == len_to_deq);
1347 n_bytes += n_peeked;
1348 chain_b->current_length = n_peeked;
1349 chain_b->next_buffer = 0;
1351 /* update previous buffer */
1352 prev_b->next_buffer = chain_bi;
1353 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1355 max_deq_bytes -= n_peeked;
1356 b[0]->total_length_not_including_first_buffer += n_peeked;
1359 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1360 /* burst */ 0, /* update_snd_nxt */ 0);
1362 if (PREDICT_FALSE (n_bufs))
1364 clib_warning ("not all buffers consumed");
1365 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1369 ASSERT (n_bytes > 0);
1370 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1376 * Build a retransmit segment
1378 * @return the number of bytes in the segment or 0 if there's nothing to
1382 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1383 tcp_connection_t * tc, u32 offset,
1384 u32 max_deq_bytes, vlib_buffer_t ** b)
1386 u32 start, available_bytes;
1389 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1390 ASSERT (max_deq_bytes != 0);
1393 * Make sure we can retransmit something
1395 available_bytes = transport_max_tx_dequeue (&tc->connection);
1396 ASSERT (available_bytes >= offset);
1397 available_bytes -= offset;
1398 if (!available_bytes)
1401 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1402 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1404 /* Start is beyond snd_congestion */
1405 start = tc->snd_una + offset;
1406 if (seq_geq (start, tc->snd_congestion))
1409 /* Don't overshoot snd_congestion */
1410 if (seq_gt (start + max_deq_bytes, tc->snd_congestion))
1412 max_deq_bytes = tc->snd_congestion - start;
1413 if (max_deq_bytes == 0)
1417 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1421 if (tcp_in_fastrecovery (tc))
1423 tc->snd_rxt_bytes += n_bytes;
1424 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1425 tcp_bt_track_rxt (tc, start, start + n_bytes);
1428 tc->bytes_retrans += n_bytes;
1429 tc->segs_retrans += 1;
1430 TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1435 * Reset congestion control, switch cwnd to loss window and try again.
1438 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1440 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 6);
1441 tc->prev_ssthresh = tc->ssthresh;
1442 tc->prev_cwnd = tc->cwnd;
1444 /* Clear fast recovery state if needed */
1445 if (tcp_in_fastrecovery (tc))
1446 tcp_cc_fastrecovery_clear (tc);
1448 /* Let cc algo decide loss cwnd and ssthresh */
1451 /* Start again from the beginning */
1452 tc->snd_congestion = tc->snd_nxt;
1453 tc->rcv_dupacks = 0;
1455 tc->cwnd_acc_bytes = 0;
1456 tc->tr_occurences += 1;
1457 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 2 * tc->snd_mss);
1458 tcp_recovery_on (tc);
1462 tcp_timer_retransmit_handler (u32 tc_index)
1464 u32 thread_index = vlib_get_thread_index ();
1465 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1466 vlib_main_t *vm = wrk->vm;
1467 tcp_connection_t *tc;
1468 vlib_buffer_t *b = 0;
1471 tc = tcp_connection_get (tc_index, thread_index);
1473 /* Note: the connection may have been closed and pool_put */
1474 if (PREDICT_FALSE (tc == 0 || tc->state == TCP_STATE_SYN_SENT))
1477 tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
1479 /* Wait-close and retransmit could pop at the same time */
1480 if (tc->state == TCP_STATE_CLOSED)
1483 if (tc->state >= TCP_STATE_ESTABLISHED)
1485 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1487 /* Lost FIN, retransmit and return */
1488 if (tc->flags & TCP_CONN_FINSNT)
1492 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1496 /* Shouldn't be here. This condition is tricky because it has to take
1497 * into account boff > 0 due to persist timeout. */
1498 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1499 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1500 && !tcp_flight_size (tc)))
1502 ASSERT (!tcp_in_recovery (tc));
1507 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1508 * to persist timer timeout */
1509 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1512 tcp_update_rto (tc);
1515 /* Peer is dead or network connectivity is lost. Close connection.
1516 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1517 * a min rto of 0.2s we need to retry about 8 times. */
1518 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1520 tcp_send_reset (tc);
1521 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1522 session_transport_closing_notify (&tc->connection);
1523 tcp_connection_timers_reset (tc);
1524 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1528 /* Increment RTO backoff (also equal to number of retries) and go back
1529 * to first un-acked byte */
1532 /* TODO be less aggressive about clearing scoreboard */
1533 scoreboard_clear (&tc->sack_sb);
1535 /* First retransmit timeout */
1536 if (tc->rto_boff == 1)
1538 tcp_cc_init_rxt_timeout (tc);
1539 /* Record timestamp. Eifel detection algorithm RFC3522 */
1540 tc->snd_rxt_ts = tcp_tstamp (tc);
1543 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1544 tcp_bt_flush_samples (tc);
1546 /* If we've sent beyond snd_congestion, update it */
1547 tc->snd_congestion = seq_max (tc->snd_nxt, tc->snd_congestion);
1548 tc->snd_nxt = tc->snd_una;
1550 /* Send one segment. n_bytes may be zero due to buffer shortfall */
1551 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1554 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1558 bi = vlib_get_buffer_index (vm, b);
1559 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1561 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1562 tcp_retransmit_timer_force_update (tc);
1564 /* Retransmit SYN-ACK */
1565 else if (tc->state == TCP_STATE_SYN_RCVD)
1567 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1571 /* Passive open establish timeout */
1572 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1574 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1575 tcp_connection_timers_reset (tc);
1576 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
1580 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1582 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1587 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1588 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1590 tcp_retransmit_timer_force_update (tc);
1592 b = vlib_get_buffer (vm, bi);
1593 tcp_init_buffer (vm, b);
1594 tcp_make_synack (tc, b);
1595 TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 1);
1597 /* Retransmit timer already updated, just enqueue to output */
1598 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1602 ASSERT (tc->state == TCP_STATE_CLOSED);
1608 * SYN retransmit timer handler. Active open only.
1611 tcp_timer_retransmit_syn_handler (u32 tc_index)
1613 u32 thread_index = vlib_get_thread_index ();
1614 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1615 vlib_main_t *vm = wrk->vm;
1616 tcp_connection_t *tc;
1617 vlib_buffer_t *b = 0;
1620 tc = tcp_half_open_connection_get (tc_index);
1622 /* Note: the connection may have transitioned to ESTABLISHED... */
1623 if (PREDICT_FALSE (tc == 0 || tc->state != TCP_STATE_SYN_SENT))
1626 tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1628 /* Half-open connection actually moved to established but we were
1629 * waiting for syn retransmit to pop to call cleanup from the right
1631 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1633 if (tcp_half_open_connection_cleanup (tc))
1634 TCP_DBG ("could not remove half-open connection");
1638 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2);
1641 /* Active open establish timeout */
1642 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1644 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
1645 tcp_connection_cleanup (tc);
1649 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1651 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1655 /* Try without increasing RTO a number of times. If this fails,
1656 * start growing RTO exponentially */
1658 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1659 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1661 b = vlib_get_buffer (vm, bi);
1662 tcp_init_buffer (vm, b);
1663 tcp_make_syn (tc, b);
1665 TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 0);
1667 /* This goes straight to ipx_lookup */
1668 tcp_push_ip_hdr (wrk, tc, b);
1669 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1671 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1672 tc->rto * TCP_TO_TIMER_TICK);
1676 * Got 0 snd_wnd from peer, try to do something about it.
1680 tcp_timer_persist_handler (u32 index)
1682 u32 thread_index = vlib_get_thread_index ();
1683 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1684 u32 bi, max_snd_bytes, available_bytes, offset;
1685 tcp_main_t *tm = vnet_get_tcp_main ();
1686 vlib_main_t *vm = wrk->vm;
1687 tcp_connection_t *tc;
1692 tc = tcp_connection_get_if_valid (index, thread_index);
1696 /* Make sure timer handle is set to invalid */
1697 tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID;
1699 /* Problem already solved or worse */
1700 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1701 || (tc->flags & TCP_CONN_FINSNT))
1704 available_bytes = transport_max_tx_dequeue (&tc->connection);
1705 offset = tc->snd_nxt - tc->snd_una;
1707 /* Reprogram persist if no new bytes available to send. We may have data
1709 if (!available_bytes)
1711 tcp_persist_timer_set (tc);
1715 if (available_bytes <= offset)
1717 ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
1721 /* Increment RTO backoff */
1723 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1726 * Try to force the first unsent segment (or buffer)
1728 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1730 tcp_persist_timer_set (tc);
1733 b = vlib_get_buffer (vm, bi);
1734 data = tcp_init_buffer (vm, b);
1736 tcp_validate_txf_size (tc, offset);
1737 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1738 max_snd_bytes = clib_min (tc->snd_mss,
1739 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1740 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1742 b->current_length = n_bytes;
1743 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1744 || tc->snd_nxt == tc->snd_una_max
1745 || tc->rto_boff > 1));
1747 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1748 /* burst */ 0, /* update_snd_nxt */ 1);
1749 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1750 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1751 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1753 /* Just sent new data, enable retransmit */
1754 tcp_retransmit_timer_update (tc);
1758 * Retransmit first unacked segment
1761 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1763 vlib_main_t *vm = wrk->vm;
1767 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 1);
1769 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1773 bi = vlib_get_buffer_index (vm, b);
1774 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1780 tcp_fast_retransmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1783 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1784 vlib_main_t *vm = wrk->vm;
1785 vlib_buffer_t *b = 0;
1787 offset = tc->snd_nxt - tc->snd_una;
1788 available_wnd = tc->snd_wnd - offset;
1789 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1791 while (n_segs < burst_size)
1793 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1797 bi = vlib_get_buffer_index (vm, b);
1798 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1799 offset += n_written;
1802 tc->snd_nxt += n_written;
1803 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1810 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1811 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1812 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1815 * Do fast retransmit with SACKs
1818 tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1821 u32 n_written = 0, offset, max_bytes, n_segs = 0, n_segs_now;
1822 sack_scoreboard_hole_t *hole;
1823 vlib_main_t *vm = wrk->vm;
1824 vlib_buffer_t *b = 0;
1825 sack_scoreboard_t *sb;
1828 u8 snd_limited = 0, can_rescue = 0;
1830 ASSERT (tcp_in_fastrecovery (tc));
1832 snd_space = tcp_available_cc_snd_space (tc);
1833 if (snd_space < tc->snd_mss)
1835 tcp_program_fastretransmit (tc);
1839 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
1841 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1843 max_deq = transport_max_tx_dequeue (&tc->connection);
1844 max_deq -= tc->snd_nxt - tc->snd_una;
1846 while (snd_space > 0 && n_segs < burst_size)
1848 hole = scoreboard_next_rxt_hole (sb, hole, max_deq, &can_rescue,
1854 snd_space = clib_min (max_deq, snd_space);
1855 burst_size = clib_min (burst_size - n_segs,
1856 snd_space / tc->snd_mss);
1857 n_segs_now = tcp_fast_retransmit_unsent (wrk, tc, burst_size);
1858 if (max_deq > n_segs_now * tc->snd_mss)
1859 tcp_program_fastretransmit (tc);
1860 n_segs += n_segs_now;
1864 if (!can_rescue || scoreboard_rescue_rxt_valid (sb, tc))
1867 /* If rescue rxt undefined or less than snd_una then one segment of
1868 * up to SMSS octets that MUST include the highest outstanding
1869 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1870 * RecoveryPoint. HighRxt MUST NOT be updated.
1872 max_bytes = clib_min (tc->snd_mss,
1873 tc->snd_congestion - tc->snd_una);
1874 max_bytes = clib_min (max_bytes, snd_space);
1875 offset = tc->snd_congestion - tc->snd_una - max_bytes;
1876 sb->rescue_rxt = tc->snd_congestion;
1877 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1882 bi = vlib_get_buffer_index (vm, b);
1883 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1888 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1889 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1893 offset = sb->high_rxt - tc->snd_una;
1894 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1896 ASSERT (n_written <= snd_space);
1898 /* Nothing left to retransmit */
1902 bi = vlib_get_buffer_index (vm, b);
1903 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1905 sb->high_rxt += n_written;
1906 snd_space -= n_written;
1911 tcp_program_fastretransmit (tc);
1918 * Fast retransmit without SACK info
1921 tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1924 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now;
1925 vlib_main_t *vm = wrk->vm;
1926 int snd_space, n_segs = 0;
1929 ASSERT (tcp_in_fastrecovery (tc));
1930 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
1932 snd_space = tcp_available_cc_snd_space (tc);
1934 if (!tcp_fastrecovery_first (tc))
1937 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1939 while (snd_space > 0 && n_segs < burst_size)
1941 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1944 /* Nothing left to retransmit */
1948 bi = vlib_get_buffer_index (vm, b);
1949 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1950 snd_space -= n_written;
1951 offset += n_written;
1955 if (n_segs == burst_size)
1960 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1961 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1964 max_deq = transport_max_tx_dequeue (&tc->connection);
1965 max_deq -= tc->snd_nxt - tc->snd_una;
1968 snd_space = clib_min (max_deq, snd_space);
1969 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1970 n_segs_now = tcp_fast_retransmit_unsent (wrk, tc, burst_size);
1971 if (max_deq > n_segs_now * tc->snd_mss)
1972 tcp_program_fastretransmit (tc);
1973 n_segs += n_segs_now;
1977 tcp_fastrecovery_first_off (tc);
1982 * Do fast retransmit
1985 tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1988 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1989 return tcp_fast_retransmit_sack (wrk, tc, burst_size);
1991 return tcp_fast_retransmit_no_sack (wrk, tc, burst_size);
1995 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1999 if (!tc->pending_dupacks)
2005 /* If we're supposed to send dupacks but have no ooo data
2006 * send only one ack */
2007 if (!vec_len (tc->snd_sacks))
2013 /* Start with first sack block */
2014 tc->snd_sack_pos = 0;
2016 /* Generate enough dupacks to cover all sack blocks. Do not generate
2017 * more sacks than the number of packets received. But do generate at
2018 * least 3, i.e., the number needed to signal congestion, if needed. */
2019 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
2020 n_acks = clib_min (n_acks, tc->pending_dupacks);
2021 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
2022 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
2025 if (n_acks < max_burst_size)
2027 tc->pending_dupacks = 0;
2028 tc->snd_sack_pos = 0;
2029 tc->dupacks_out += n_acks;
2034 TCP_DBG ("constrained by burst size");
2035 tc->pending_dupacks = n_acks - max_burst_size;
2036 tc->dupacks_out += max_burst_size;
2037 tcp_program_dupack (tc);
2038 return max_burst_size;
2043 tcp_do_fastretransmit (tcp_connection_t * tc, u32 max_burst_size)
2045 u32 n_segs = 0, burst_size, sent_bytes, burst_bytes;
2046 tcp_worker_ctx_t *wrk;
2048 wrk = tcp_get_worker (tc->c_thread_index);
2049 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection,
2051 clib_time.last_cpu_time);
2052 burst_size = clib_min (max_burst_size, burst_bytes / tc->snd_mss);
2055 tcp_program_fastretransmit (tc);
2059 n_segs = tcp_fast_retransmit (wrk, tc, burst_size);
2060 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2061 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
2066 tcp_session_custom_tx (void *conn, u32 max_burst_size)
2068 tcp_connection_t *tc = (tcp_connection_t *) conn;
2071 if (tcp_in_fastrecovery (tc) && (tc->flags & TCP_CONN_FRXT_PENDING))
2073 tc->flags &= ~TCP_CONN_FRXT_PENDING;
2074 n_segs = tcp_do_fastretransmit (tc, max_burst_size);
2075 max_burst_size -= n_segs;
2078 if (!(tc->flags & TCP_CONN_SNDACK))
2081 tc->flags &= ~TCP_CONN_SNDACK;
2083 /* We have retransmitted packets and no dupack */
2084 if (n_segs && !tc->pending_dupacks)
2087 if (!max_burst_size)
2089 tcp_program_ack (tc);
2090 return max_burst_size;
2093 n_segs += tcp_send_acks (tc, max_burst_size);
2097 #endif /* CLIB_MARCH_VARIANT */
2100 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2101 u16 * next0, u32 * error0)
2103 ip_adjacency_t *adj;
2106 /* Not thread safe but as long as the connection exists the adj should
2108 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2110 if (ai == ADJ_INDEX_INVALID)
2112 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2113 *next0 = TCP_OUTPUT_NEXT_DROP;
2114 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2119 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2120 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2121 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2122 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2125 *next0 = TCP_OUTPUT_NEXT_DROP;
2126 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2128 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2132 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2133 u32 * to_next, u32 n_bufs)
2135 u32 n_trace = vlib_get_trace_count (vm, node);
2136 tcp_connection_t *tc;
2142 for (i = 0; i < clib_min (n_trace, n_bufs); i++)
2144 b = vlib_get_buffer (vm, to_next[i]);
2145 th = vlib_buffer_get_current (b);
2146 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2148 t = vlib_add_trace (vm, node, b, sizeof (*t));
2149 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2150 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2155 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2156 tcp_connection_t * tc0, u8 is_ip4)
2158 tcp_header_t *th0 = 0;
2160 th0 = vlib_buffer_get_current (b0);
2161 TCP_EVT_DBG (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length);
2164 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2165 IP_PROTOCOL_TCP, 1);
2166 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
2167 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
2173 ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6,
2174 &tc0->c_rmt_ip6, IP_PROTOCOL_TCP);
2175 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
2176 vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data;
2177 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
2183 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2184 u32 * error0, u16 * next0, u8 is_ip4)
2187 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2189 *error0 = TCP_ERROR_INVALID_CONNECTION;
2190 *next0 = TCP_OUTPUT_NEXT_DROP;
2194 /* If next_index is not drop use it */
2195 if (tc0->next_node_index)
2197 *next0 = tc0->next_node_index;
2198 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2201 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2202 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2206 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2207 tcp_output_handle_link_local (tc0, b0, next0, error0);
2210 if (!TCP_ALWAYS_ACK)
2211 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
2217 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2218 vlib_frame_t * frame, int is_ip4)
2220 u32 n_left_from, *from, thread_index = vm->thread_index;
2221 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2222 u16 nexts[VLIB_FRAME_SIZE], *next;
2224 from = vlib_frame_vector_args (frame);
2225 n_left_from = frame->n_vectors;
2226 tcp_set_time_now (tcp_get_worker (thread_index));
2228 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2229 tcp46_output_trace_frame (vm, node, from, n_left_from);
2231 vlib_get_buffers (vm, from, bufs, n_left_from);
2235 while (n_left_from >= 4)
2237 u32 error0 = TCP_ERROR_PKTS_SENT, error1 = TCP_ERROR_PKTS_SENT;
2238 tcp_connection_t *tc0, *tc1;
2241 vlib_prefetch_buffer_header (b[2], STORE);
2242 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2244 vlib_prefetch_buffer_header (b[3], STORE);
2245 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2248 next[0] = next[1] = TCP_OUTPUT_NEXT_IP_LOOKUP;
2250 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2252 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2255 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2256 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2258 tcp_output_handle_packet (tc0, b[0], &error0, &next[0], is_ip4);
2259 tcp_output_handle_packet (tc1, b[1], &error1, &next[1], is_ip4);
2265 while (n_left_from > 0)
2267 u32 error0 = TCP_ERROR_PKTS_SENT;
2268 tcp_connection_t *tc0;
2270 if (n_left_from > 1)
2272 vlib_prefetch_buffer_header (b[1], STORE);
2273 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2276 next[0] = TCP_OUTPUT_NEXT_IP_LOOKUP;
2277 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2280 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2281 tcp_output_handle_packet (tc0, b[0], &error0, &next[0], is_ip4);
2288 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2289 return frame->n_vectors;
2292 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2293 vlib_frame_t * from_frame)
2295 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2298 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2299 vlib_frame_t * from_frame)
2301 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2305 VLIB_REGISTER_NODE (tcp4_output_node) =
2307 .name = "tcp4-output",
2308 /* Takes a vector of packets. */
2309 .vector_size = sizeof (u32),
2310 .n_errors = TCP_N_ERROR,
2311 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2312 .error_strings = tcp_error_strings,
2313 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2315 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2316 foreach_tcp4_output_next
2319 .format_buffer = format_tcp_header,
2320 .format_trace = format_tcp_tx_trace,
2325 VLIB_REGISTER_NODE (tcp6_output_node) =
2327 .name = "tcp6-output",
2328 /* Takes a vector of packets. */
2329 .vector_size = sizeof (u32),
2330 .n_errors = TCP_N_ERROR,
2331 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2332 .error_strings = tcp_error_strings,
2333 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2335 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2336 foreach_tcp6_output_next
2339 .format_buffer = format_tcp_header,
2340 .format_trace = format_tcp_tx_trace,
2344 typedef enum _tcp_reset_next
2346 TCP_RESET_NEXT_DROP,
2347 TCP_RESET_NEXT_IP_LOOKUP,
2351 #define foreach_tcp4_reset_next \
2352 _(DROP, "error-drop") \
2353 _(IP_LOOKUP, "ip4-lookup")
2355 #define foreach_tcp6_reset_next \
2356 _(DROP, "error-drop") \
2357 _(IP_LOOKUP, "ip6-lookup")
2360 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2361 vlib_frame_t * from_frame, u8 is_ip4)
2363 u32 n_left_from, next_index, *from, *to_next;
2364 u32 my_thread_index = vm->thread_index;
2366 from = vlib_frame_vector_args (from_frame);
2367 n_left_from = from_frame->n_vectors;
2369 next_index = node->cached_next_index;
2371 while (n_left_from > 0)
2375 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2377 while (n_left_from > 0 && n_left_to_next > 0)
2383 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2390 n_left_to_next -= 1;
2392 b0 = vlib_get_buffer (vm, bi0);
2394 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2395 my_thread_index, is_ip4))
2397 error0 = TCP_ERROR_LOOKUP_DROPS;
2398 next0 = TCP_RESET_NEXT_DROP;
2402 /* Prepare to send to IP lookup */
2403 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2404 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2407 b0->error = node->errors[error0];
2408 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2409 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2411 th0 = vlib_buffer_get_current (b0);
2413 th0 = ip4_next_header ((ip4_header_t *) th0);
2415 th0 = ip6_next_header ((ip6_header_t *) th0);
2416 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2417 clib_memcpy_fast (&t0->tcp_header, th0,
2418 sizeof (t0->tcp_header));
2421 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2422 n_left_to_next, bi0, next0);
2424 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2426 return from_frame->n_vectors;
2429 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2430 vlib_frame_t * from_frame)
2432 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2435 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2436 vlib_frame_t * from_frame)
2438 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2442 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2443 .name = "tcp4-reset",
2444 .vector_size = sizeof (u32),
2445 .n_errors = TCP_N_ERROR,
2446 .error_strings = tcp_error_strings,
2447 .n_next_nodes = TCP_RESET_N_NEXT,
2449 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2450 foreach_tcp4_reset_next
2453 .format_trace = format_tcp_tx_trace,
2458 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2459 .name = "tcp6-reset",
2460 .vector_size = sizeof (u32),
2461 .n_errors = TCP_N_ERROR,
2462 .error_strings = tcp_error_strings,
2463 .n_next_nodes = TCP_RESET_N_NEXT,
2465 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2466 foreach_tcp6_reset_next
2469 .format_trace = format_tcp_tx_trace,
2474 * fd.io coding-style-patch-verification: ON
2477 * eval: (c-set-style "gnu")