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>
17 #include <vnet/tcp/tcp_inlines.h>
19 #include <vnet/ip/ip4_inlines.h>
20 #include <vnet/ip/ip6_inlines.h>
22 typedef enum _tcp_output_next
25 TCP_OUTPUT_NEXT_IP_LOOKUP,
26 TCP_OUTPUT_NEXT_IP_REWRITE,
27 TCP_OUTPUT_NEXT_IP_ARP,
31 #define foreach_tcp4_output_next \
32 _ (DROP, "error-drop") \
33 _ (IP_LOOKUP, "ip4-lookup") \
34 _ (IP_REWRITE, "ip4-rewrite") \
37 #define foreach_tcp6_output_next \
38 _ (DROP, "error-drop") \
39 _ (IP_LOOKUP, "ip6-lookup") \
40 _ (IP_REWRITE, "ip6-rewrite") \
41 _ (IP_ARP, "ip6-discover-neighbor")
43 static char *tcp_error_strings[] = {
44 #define tcp_error(n,s) s,
45 #include <vnet/tcp/tcp_error.def>
51 tcp_header_t tcp_header;
52 tcp_connection_t tcp_connection;
56 format_tcp_tx_trace (u8 * s, va_list * args)
58 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
59 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
60 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
61 tcp_connection_t *tc = &t->tcp_connection;
62 u32 indent = format_get_indent (s);
64 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
65 format_tcp_state, tc->state, format_white_space, indent,
66 format_tcp_header, &t->tcp_header, 128);
71 #ifndef CLIB_MARCH_VARIANT
73 tcp_window_compute_scale (u32 window)
76 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
82 * TCP's initial window
85 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
87 /* RFC 6928 recommends the value lower. However at the time our connections
88 * are initialized, fifos may not be allocated. Therefore, advertise the
89 * smallest possible unscaled window size and update once fifos are
90 * assigned to the session.
93 tcp_update_rcv_mss (tc);
94 TCP_IW_N_SEGMENTS * tc->mss;
96 return tcp_cfg.min_rx_fifo;
100 * Compute initial window and scale factor. As per RFC1323, window field in
101 * SYN and SYN-ACK segments is never scaled.
104 tcp_initial_window_to_advertise (tcp_connection_t * tc)
106 /* Compute rcv wscale only if peer advertised support for it */
107 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
108 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
110 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
112 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
116 tcp_update_rcv_wnd (tcp_connection_t * tc)
118 u32 available_space, wnd;
122 * Figure out how much space we have available
124 available_space = transport_max_rx_enqueue (&tc->connection);
127 * Use the above and what we know about what we've previously advertised
128 * to compute the new window
130 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
132 /* Check if we are about to retract the window. Do the comparison before
133 * rounding to avoid errors. Per RFC7323 sec. 2.4 we could remove this */
134 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
136 wnd = round_down_pow2 (clib_max (observed_wnd, 0), 1 << tc->rcv_wscale);
137 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
141 /* Make sure we have a multiple of 1 << rcv_wscale. We round down to
142 * avoid advertising a window larger than what can be buffered */
143 wnd = round_down_pow2 (available_space, 1 << tc->rcv_wscale);
146 if (PREDICT_FALSE (wnd < tc->rcv_opts.mss))
149 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
153 * Compute and return window to advertise, scaled as per RFC1323
156 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
158 if (state < TCP_STATE_ESTABLISHED)
159 return tcp_initial_window_to_advertise (tc);
161 tcp_update_rcv_wnd (tc);
162 return tc->rcv_wnd >> tc->rcv_wscale;
166 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
170 opts->flags |= TCP_OPTS_FLAG_MSS;
172 len += TCP_OPTION_LEN_MSS;
174 opts->flags |= TCP_OPTS_FLAG_WSCALE;
175 opts->wscale = tc->rcv_wscale;
176 len += TCP_OPTION_LEN_WINDOW_SCALE;
178 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
179 opts->tsval = tcp_time_now ();
181 len += TCP_OPTION_LEN_TIMESTAMP;
185 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
186 len += TCP_OPTION_LEN_SACK_PERMITTED;
189 /* Align to needed boundary */
190 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
195 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
199 opts->flags |= TCP_OPTS_FLAG_MSS;
201 len += TCP_OPTION_LEN_MSS;
203 if (tcp_opts_wscale (&tc->rcv_opts))
205 opts->flags |= TCP_OPTS_FLAG_WSCALE;
206 opts->wscale = tc->rcv_wscale;
207 len += TCP_OPTION_LEN_WINDOW_SCALE;
210 if (tcp_opts_tstamp (&tc->rcv_opts))
212 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
213 opts->tsval = tcp_time_now ();
214 opts->tsecr = tc->tsval_recent;
215 len += TCP_OPTION_LEN_TIMESTAMP;
218 if (tcp_opts_sack_permitted (&tc->rcv_opts))
220 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
221 len += TCP_OPTION_LEN_SACK_PERMITTED;
224 /* Align to needed boundary */
225 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
230 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
236 if (tcp_opts_tstamp (&tc->rcv_opts))
238 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
239 opts->tsval = tcp_tstamp (tc);
240 opts->tsecr = tc->tsval_recent;
241 len += TCP_OPTION_LEN_TIMESTAMP;
243 if (tcp_opts_sack_permitted (&tc->rcv_opts))
245 if (vec_len (tc->snd_sacks))
247 opts->flags |= TCP_OPTS_FLAG_SACK;
248 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
249 tc->snd_sack_pos = 0;
250 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
251 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
252 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
253 TCP_OPTS_MAX_SACK_BLOCKS);
254 tc->snd_sack_pos += opts->n_sack_blocks;
255 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
259 /* Align to needed boundary */
260 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
265 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
270 case TCP_STATE_ESTABLISHED:
271 case TCP_STATE_CLOSE_WAIT:
272 case TCP_STATE_FIN_WAIT_1:
273 case TCP_STATE_LAST_ACK:
274 case TCP_STATE_CLOSING:
275 case TCP_STATE_FIN_WAIT_2:
276 case TCP_STATE_TIME_WAIT:
277 case TCP_STATE_CLOSED:
278 return tcp_make_established_options (tc, opts);
279 case TCP_STATE_SYN_RCVD:
280 return tcp_make_synack_options (tc, opts);
281 case TCP_STATE_SYN_SENT:
282 return tcp_make_syn_options (tc, opts);
284 clib_warning ("State not handled! %d", state);
290 * Update burst send vars
292 * - Updates snd_mss to reflect the effective segment size that we can send
293 * by taking into account all TCP options, including SACKs.
294 * - Cache 'on the wire' options for reuse
295 * - Updates receive window which can be reused for a burst.
297 * This should *only* be called when doing bursts
300 tcp_update_burst_snd_vars (tcp_connection_t * tc)
302 tcp_main_t *tm = &tcp_main;
304 /* Compute options to be used for connection. These may be reused when
305 * sending data or to compute the effective mss (snd_mss) */
306 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
307 TCP_STATE_ESTABLISHED);
309 /* XXX check if MTU has been updated */
310 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
311 ASSERT (tc->snd_mss > 0);
313 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
316 tcp_update_rcv_wnd (tc);
318 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
319 tcp_bt_check_app_limited (tc);
321 if (tc->snd_una == tc->snd_nxt)
323 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
324 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST);
328 #endif /* CLIB_MARCH_VARIANT */
331 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
333 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
334 vlib_buffer_free_one (vm, b->next_buffer);
335 /* Zero all flags but free list index and trace flag */
336 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
338 b->current_length = 0;
339 b->total_length_not_including_first_buffer = 0;
340 vnet_buffer (b)->tcp.flags = 0;
342 /* Leave enough space for headers */
343 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
346 #ifndef CLIB_MARCH_VARIANT
348 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
350 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
351 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
352 b->total_length_not_including_first_buffer = 0;
354 vnet_buffer (b)->tcp.flags = 0;
355 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
356 /* Leave enough space for headers */
357 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
361 /* Compute TCP checksum in software when offloading is disabled for a connection */
363 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
364 ip46_address_t * src, ip46_address_t * dst)
367 u16 payload_length_host_byte_order;
370 /* Initialize checksum with ip header. */
371 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
372 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
373 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
375 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
377 sum0 = ip_csum_with_carry
378 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
379 sum0 = ip_csum_with_carry
380 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
383 return ip_calculate_l4_checksum (vm, p0, sum0,
384 payload_length_host_byte_order, NULL, 0,
389 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
390 ip46_address_t * src, ip46_address_t * dst)
393 u32 payload_length_host_byte_order;
395 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
397 clib_host_to_net_u32 (payload_length_host_byte_order +
398 (IP_PROTOCOL_TCP << 16));
400 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
401 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
403 return ip_calculate_l4_checksum (vm, p0, sum0,
404 payload_length_host_byte_order, NULL, 0,
409 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
412 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
414 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
415 vlib_main_t *vm = wrk->vm;
418 checksum = ip4_tcp_compute_checksum_custom
419 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
421 checksum = ip6_tcp_compute_checksum_custom
422 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
426 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
435 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
438 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
439 u8 tcp_opts_len, tcp_hdr_opts_len;
443 wnd = tcp_window_to_advertise (tc, state);
445 /* Make and write options */
446 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
447 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
449 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
450 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
452 tcp_options_write ((u8 *) (th + 1), snd_opts);
454 th->checksum = tcp_compute_checksum (tc, b);
456 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
459 tcp_zero_rwnd_sent_on (tc);
461 tcp_zero_rwnd_sent_off (tc);
465 * Convert buffer to ACK
468 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
470 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
471 TCP_EVT (TCP_EVT_ACK_SENT, tc);
472 tc->rcv_las = tc->rcv_nxt;
476 * Convert buffer to FIN-ACK
479 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
481 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
485 * Convert buffer to SYN
488 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
490 u8 tcp_hdr_opts_len, tcp_opts_len;
493 tcp_options_t snd_opts;
495 initial_wnd = tcp_initial_window_to_advertise (tc);
497 /* Make and write options */
498 clib_memset (&snd_opts, 0, sizeof (snd_opts));
499 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
500 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
502 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
503 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
505 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
506 tcp_options_write ((u8 *) (th + 1), &snd_opts);
507 th->checksum = tcp_compute_checksum (tc, b);
511 * Convert buffer to SYN-ACK
514 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
516 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
517 u8 tcp_opts_len, tcp_hdr_opts_len;
521 clib_memset (snd_opts, 0, sizeof (*snd_opts));
522 initial_wnd = tcp_initial_window_to_advertise (tc);
523 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
524 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
526 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
527 tc->rcv_nxt, tcp_hdr_opts_len,
528 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
529 tcp_options_write ((u8 *) (th + 1), snd_opts);
531 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
532 th->checksum = tcp_compute_checksum (tc, b);
536 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
537 u8 is_ip4, u32 fib_index)
539 tcp_main_t *tm = &tcp_main;
540 vlib_main_t *vm = wrk->vm;
542 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
545 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
546 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
548 tcp_trajectory_add_start (b, 1);
550 session_add_pending_tx_buffer (vm->thread_index, bi,
551 tm->ipl_next_node[!is_ip4]);
553 if (vm->thread_index == 0 && vlib_num_workers ())
554 session_queue_run_on_main_thread (wrk->vm);
558 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
561 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
564 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
565 wrk->tco_next_node[!is_ip4]);
568 #endif /* CLIB_MARCH_VARIANT */
571 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b, u8 is_ip4)
576 ip4_address_t src_ip4, dst_ip4;
577 ip6_address_t src_ip6, dst_ip6;
578 u16 src_port, dst_port;
579 u32 tmp, len, seq, ack;
582 /* Find IP and TCP headers */
583 th = tcp_buffer_hdr (b);
585 /* Save src and dst ip */
588 ih4 = vlib_buffer_get_current (b);
589 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
590 src_ip4.as_u32 = ih4->src_address.as_u32;
591 dst_ip4.as_u32 = ih4->dst_address.as_u32;
595 ih6 = vlib_buffer_get_current (b);
596 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
597 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
598 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
601 src_port = th->src_port;
602 dst_port = th->dst_port;
603 flags = TCP_FLAG_RST;
606 * RFC 793. If the ACK bit is off, sequence number zero is used,
607 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
608 * If the ACK bit is on,
609 * <SEQ=SEG.ACK><CTL=RST>
613 seq = th->ack_number;
618 flags |= TCP_FLAG_ACK;
619 tmp = clib_net_to_host_u32 (th->seq_number);
620 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
621 ack = clib_host_to_net_u32 (tmp + len);
625 tcp_reuse_buffer (vm, b);
626 tcp_trajectory_add_start (b, 4);
627 th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack,
628 sizeof (tcp_header_t), flags, 0);
632 ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4,
634 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
639 ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP);
640 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
647 #ifndef CLIB_MARCH_VARIANT
649 * Send reset without reusing existing buffer
651 * It extracts connection info out of original packet
654 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
655 u32 thread_index, u8 is_ip4)
657 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
658 vlib_main_t *vm = wrk->vm;
660 u32 bi, sw_if_index, fib_index;
661 u8 tcp_hdr_len, flags = 0;
662 tcp_header_t *th, *pkt_th;
664 ip4_header_t *ih4, *pkt_ih4;
665 ip6_header_t *ih6, *pkt_ih6;
666 fib_protocol_t fib_proto;
668 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
670 tcp_worker_stats_inc (wrk, no_buffer, 1);
674 b = vlib_get_buffer (vm, bi);
675 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
676 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
677 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
678 tcp_init_buffer (vm, b);
680 /* Make and write options */
681 tcp_hdr_len = sizeof (tcp_header_t);
685 pkt_ih4 = vlib_buffer_get_current (pkt);
686 pkt_th = ip4_next_header (pkt_ih4);
690 pkt_ih6 = vlib_buffer_get_current (pkt);
691 pkt_th = ip6_next_header (pkt_ih6);
694 if (tcp_ack (pkt_th))
696 flags = TCP_FLAG_RST;
697 seq = pkt_th->ack_number;
698 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
702 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
704 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
707 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
708 seq, ack, tcp_hdr_len, flags, 0);
710 /* Swap src and dst ip */
713 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
714 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
715 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
716 tcp_csum_offload (tc));
717 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
722 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
724 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
725 &pkt_ih6->src_address,
727 tc->ipv6_flow_label);
728 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
732 tcp_enqueue_to_ip_lookup (wrk, b, bi, is_ip4, fib_index);
733 TCP_EVT (TCP_EVT_RST_SENT, tc);
734 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
735 TCP_ERROR_RST_SENT, 1);
739 * Build and set reset packet for connection
742 tcp_send_reset (tcp_connection_t * tc)
744 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
745 vlib_main_t *vm = wrk->vm;
749 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
752 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
754 tcp_worker_stats_inc (wrk, no_buffer, 1);
757 b = vlib_get_buffer (vm, bi);
758 tcp_init_buffer (vm, b);
760 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
761 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
762 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
763 flags = TCP_FLAG_RST;
764 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
765 tc->rcv_nxt, tcp_hdr_opts_len, flags,
767 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
768 th->checksum = tcp_compute_checksum (tc, b);
769 ASSERT (opts_write_len == tc->snd_opts_len);
770 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
771 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
772 TCP_EVT (TCP_EVT_RST_SENT, tc);
773 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
774 TCP_ERROR_RST_SENT, 1);
778 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
783 vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4,
784 IP_PROTOCOL_TCP, tcp_csum_offload (tc));
788 vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6,
789 IP_PROTOCOL_TCP, tc->ipv6_flow_label);
796 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
797 * The packet is not forwarded through tcpx_output to avoid doing lookups
798 * in the half_open pool.
801 tcp_send_syn (tcp_connection_t * tc)
803 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
804 vlib_main_t *vm = wrk->vm;
809 * Setup retransmit and establish timers before requesting buffer
810 * such that we can return if we've ran out.
812 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
813 tc->rto * TCP_TO_TIMER_TICK);
815 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
817 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
818 tcp_worker_stats_inc (wrk, no_buffer, 1);
822 b = vlib_get_buffer (vm, bi);
823 tcp_init_buffer (vm, b);
824 tcp_make_syn (tc, b);
826 /* Measure RTT with this */
827 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
828 tc->rtt_seq = tc->snd_nxt;
831 tcp_push_ip_hdr (wrk, tc, b);
832 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
833 TCP_EVT (TCP_EVT_SYN_SENT, tc);
837 tcp_send_synack (tcp_connection_t * tc)
839 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
840 vlib_main_t *vm = wrk->vm;
844 ASSERT (tc->snd_una != tc->snd_nxt);
845 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
847 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
849 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
850 tcp_worker_stats_inc (wrk, no_buffer, 1);
854 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
855 b = vlib_get_buffer (vm, bi);
856 tcp_init_buffer (vm, b);
857 tcp_make_synack (tc, b);
858 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
859 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
866 tcp_send_fin (tcp_connection_t * tc)
868 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
869 vlib_main_t *vm = wrk->vm;
874 fin_snt = tc->flags & TCP_CONN_FINSNT;
878 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
880 /* Out of buffers so program fin retransmit ASAP */
881 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
885 /* Make sure retransmit retries a fin not data */
886 tc->flags |= TCP_CONN_FINSNT;
887 tcp_worker_stats_inc (wrk, no_buffer, 1);
891 /* If we have non-dupacks programmed, no need to send them */
892 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
893 tc->flags &= ~TCP_CONN_SNDACK;
895 b = vlib_get_buffer (vm, bi);
896 tcp_init_buffer (vm, b);
897 tcp_make_fin (tc, b);
898 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
899 TCP_EVT (TCP_EVT_FIN_SENT, tc);
900 /* Account for the FIN */
902 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
905 tc->flags |= TCP_CONN_FINSNT;
906 tc->flags &= ~TCP_CONN_FINPNDG;
911 * Push TCP header and update connection variables. Should only be called
912 * for segments with data, not for 'control' packets.
915 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
916 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
918 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
919 u32 advertise_wnd, data_len;
920 tcp_main_t *tm = &tcp_main;
923 data_len = b->current_length;
924 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
925 data_len += b->total_length_not_including_first_buffer;
927 vnet_buffer (b)->tcp.flags = 0;
928 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
931 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
933 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
936 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
938 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
940 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
942 if (seq_geq (tc->psh_seq, snd_nxt)
943 && seq_lt (tc->psh_seq, snd_nxt + data_len))
944 flags |= TCP_FLAG_PSH;
946 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
947 tc->rcv_nxt, tcp_hdr_opts_len, flags,
952 clib_memcpy_fast ((u8 *) (th + 1),
953 tm->wrk_ctx[tc->c_thread_index].cached_opts,
958 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
959 ASSERT (len == tc->snd_opts_len);
963 * Update connection variables
967 tc->snd_nxt += data_len;
968 tc->rcv_las = tc->rcv_nxt;
970 tc->bytes_out += data_len;
971 tc->data_segs_out += 1;
973 th->checksum = tcp_compute_checksum (tc, b);
975 TCP_EVT (TCP_EVT_PKTIZE, tc);
979 tcp_buffer_len (vlib_buffer_t * b)
981 u32 data_len = b->current_length;
982 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
983 data_len += b->total_length_not_including_first_buffer;
988 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
990 tcp_connection_t *tc = (tcp_connection_t *) tconn;
992 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
993 tcp_bt_track_tx (tc, tcp_buffer_len (b));
995 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
996 /* update_snd_nxt */ 1);
998 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
999 /* If not tracking an ACK, start tracking */
1000 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1002 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1003 tc->rtt_seq = tc->snd_nxt;
1005 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1007 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1008 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
1011 tcp_trajectory_add_start (b, 3);
1016 tcp_send_ack (tcp_connection_t * tc)
1018 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1019 vlib_main_t *vm = wrk->vm;
1023 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1025 tcp_update_rcv_wnd (tc);
1026 tcp_worker_stats_inc (wrk, no_buffer, 1);
1029 b = vlib_get_buffer (vm, bi);
1030 tcp_init_buffer (vm, b);
1031 tcp_make_ack (tc, b);
1032 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1036 tcp_program_ack (tcp_connection_t * tc)
1038 if (!(tc->flags & TCP_CONN_SNDACK))
1040 session_add_self_custom_tx_evt (&tc->connection, 1);
1041 tc->flags |= TCP_CONN_SNDACK;
1046 tcp_program_dupack (tcp_connection_t * tc)
1048 if (!(tc->flags & TCP_CONN_SNDACK))
1050 session_add_self_custom_tx_evt (&tc->connection, 1);
1051 tc->flags |= TCP_CONN_SNDACK;
1053 if (tc->pending_dupacks < 255)
1054 tc->pending_dupacks += 1;
1058 tcp_program_retransmit (tcp_connection_t * tc)
1060 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1062 session_add_self_custom_tx_evt (&tc->connection, 0);
1063 tc->flags |= TCP_CONN_RXT_PENDING;
1068 * Send window update ack
1070 * Ensures that it will be sent only once, after a zero rwnd has been
1071 * advertised in a previous ack, and only if rwnd has grown beyond a
1072 * configurable value.
1075 tcp_send_window_update_ack (tcp_connection_t * tc)
1077 if (tcp_zero_rwnd_sent (tc))
1079 tcp_update_rcv_wnd (tc);
1080 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1082 tcp_zero_rwnd_sent_off (tc);
1083 tcp_program_ack (tc);
1089 * Allocate a new buffer and build a new tcp segment
1091 * @param wrk tcp worker
1092 * @param tc connection for which the segment will be allocated
1093 * @param offset offset of the first byte in the tx fifo
1094 * @param max_deq_byte segment size
1095 * @param[out] b pointer to buffer allocated
1097 * @return the number of bytes in the segment or 0 if buffer cannot be
1098 * allocated or no data available
1101 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1102 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1104 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1105 vlib_main_t *vm = wrk->vm;
1110 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1115 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1118 * Allocate and fill in buffer(s)
1121 /* Easy case, buffer size greater than mss */
1122 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1124 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1126 tcp_worker_stats_inc (wrk, no_buffer, 1);
1129 *b = vlib_get_buffer (vm, bi);
1130 data = tcp_init_buffer (vm, *b);
1131 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1133 ASSERT (n_bytes == max_deq_bytes);
1134 b[0]->current_length = n_bytes;
1135 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1136 /* burst */ 0, /* update_snd_nxt */ 0);
1138 /* Split mss into multiple buffers */
1141 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1142 u16 n_peeked, len_to_deq;
1143 vlib_buffer_t *chain_b, *prev_b;
1146 /* Make sure we have enough buffers */
1147 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1148 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1149 CLIB_CACHE_LINE_BYTES);
1150 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1151 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1154 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1155 tcp_worker_stats_inc (wrk, no_buffer, 1);
1159 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1160 data = tcp_init_buffer (vm, *b);
1161 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1163 TRANSPORT_MAX_HDRS_LEN);
1164 b[0]->current_length = n_bytes;
1165 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1166 b[0]->total_length_not_including_first_buffer = 0;
1167 max_deq_bytes -= n_bytes;
1170 for (i = 1; i < n_bufs_per_seg; i++)
1173 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1174 chain_bi = wrk->tx_buffers[--n_bufs];
1175 chain_b = vlib_get_buffer (vm, chain_bi);
1176 chain_b->current_data = 0;
1177 data = vlib_buffer_get_current (chain_b);
1178 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1181 ASSERT (n_peeked == len_to_deq);
1182 n_bytes += n_peeked;
1183 chain_b->current_length = n_peeked;
1184 chain_b->next_buffer = 0;
1186 /* update previous buffer */
1187 prev_b->next_buffer = chain_bi;
1188 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1190 max_deq_bytes -= n_peeked;
1191 b[0]->total_length_not_including_first_buffer += n_peeked;
1194 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1195 /* burst */ 0, /* update_snd_nxt */ 0);
1197 if (PREDICT_FALSE (n_bufs))
1199 clib_warning ("not all buffers consumed");
1200 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1204 ASSERT (n_bytes > 0);
1205 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1211 * Build a retransmit segment
1213 * @return the number of bytes in the segment or 0 if there's nothing to
1217 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1218 tcp_connection_t * tc, u32 offset,
1219 u32 max_deq_bytes, vlib_buffer_t ** b)
1221 u32 start, available_bytes;
1224 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1225 ASSERT (max_deq_bytes != 0);
1228 * Make sure we can retransmit something
1230 available_bytes = transport_max_tx_dequeue (&tc->connection);
1231 ASSERT (available_bytes >= offset);
1232 available_bytes -= offset;
1233 if (!available_bytes)
1236 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1237 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1239 start = tc->snd_una + offset;
1240 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1242 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1246 tc->snd_rxt_bytes += n_bytes;
1248 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1249 tcp_bt_track_rxt (tc, start, start + n_bytes);
1251 tc->bytes_retrans += n_bytes;
1252 tc->segs_retrans += 1;
1253 tcp_worker_stats_inc (wrk, rxt_segs, 1);
1254 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1260 tcp_check_sack_reneging (tcp_connection_t * tc)
1262 sack_scoreboard_t *sb = &tc->sack_sb;
1263 sack_scoreboard_hole_t *hole;
1265 hole = scoreboard_first_hole (sb);
1266 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1269 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1273 * Reset congestion control, switch cwnd to loss window and try again.
1276 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1278 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1280 tc->prev_ssthresh = tc->ssthresh;
1281 tc->prev_cwnd = tc->cwnd;
1283 /* If we entrered loss without fast recovery, notify cc algo of the
1284 * congestion event such that it can update ssthresh and its state */
1285 if (!tcp_in_fastrecovery (tc))
1286 tcp_cc_congestion (tc);
1288 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1292 tc->cwnd_acc_bytes = 0;
1293 tc->tr_occurences += 1;
1294 tc->sack_sb.reorder = TCP_DUPACK_THRESHOLD;
1295 tcp_recovery_on (tc);
1299 tcp_timer_retransmit_handler (tcp_connection_t * tc)
1301 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1302 vlib_main_t *vm = wrk->vm;
1303 vlib_buffer_t *b = 0;
1306 tcp_worker_stats_inc (wrk, tr_events, 1);
1308 /* Should be handled by a different handler */
1309 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
1312 /* Wait-close and retransmit could pop at the same time */
1313 if (tc->state == TCP_STATE_CLOSED)
1316 if (tc->state >= TCP_STATE_ESTABLISHED)
1318 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1320 /* Lost FIN, retransmit and return */
1321 if (tc->flags & TCP_CONN_FINSNT)
1325 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1329 /* Shouldn't be here */
1330 if (tc->snd_una == tc->snd_nxt)
1332 ASSERT (!tcp_in_recovery (tc));
1337 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1338 * to persist timer timeout */
1339 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1342 tcp_update_rto (tc);
1345 /* Peer is dead or network connectivity is lost. Close connection.
1346 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1347 * a min rto of 0.2s we need to retry about 8 times. */
1348 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1350 tcp_send_reset (tc);
1351 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1352 session_transport_closing_notify (&tc->connection);
1353 session_transport_closed_notify (&tc->connection);
1354 tcp_connection_timers_reset (tc);
1355 tcp_program_cleanup (wrk, tc);
1356 tcp_worker_stats_inc (wrk, tr_abort, 1);
1360 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1361 tcp_check_sack_reneging (tc);
1363 /* Update send congestion to make sure that rxt has data to send */
1364 tc->snd_congestion = tc->snd_nxt;
1366 /* Send the first unacked segment. If we're short on buffers, return
1367 * as soon as possible */
1368 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1369 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1372 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1376 bi = vlib_get_buffer_index (vm, b);
1377 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1379 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1380 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1383 if (tc->rto_boff == 1)
1385 tcp_cc_init_rxt_timeout (tc);
1386 /* Record timestamp. Eifel detection algorithm RFC3522 */
1387 tc->snd_rxt_ts = tcp_tstamp (tc);
1390 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1391 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1393 tcp_program_retransmit (tc);
1395 /* Retransmit SYN-ACK */
1396 else if (tc->state == TCP_STATE_SYN_RCVD)
1398 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1402 /* Passive open establish timeout */
1403 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1405 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1406 tcp_connection_timers_reset (tc);
1407 tcp_program_cleanup (wrk, tc);
1408 tcp_worker_stats_inc (wrk, tr_abort, 1);
1412 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1414 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1415 tcp_worker_stats_inc (wrk, no_buffer, 1);
1420 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1421 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1423 ASSERT (tc->snd_una != tc->snd_nxt);
1424 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1426 b = vlib_get_buffer (vm, bi);
1427 tcp_init_buffer (vm, b);
1428 tcp_make_synack (tc, b);
1429 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1431 /* Retransmit timer already updated, just enqueue to output */
1432 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1436 ASSERT (tc->state == TCP_STATE_CLOSED);
1442 * SYN retransmit timer handler. Active open only.
1445 tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
1447 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1448 vlib_main_t *vm = wrk->vm;
1449 vlib_buffer_t *b = 0;
1452 /* Note: the connection may have transitioned to ESTABLISHED... */
1453 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
1456 /* Half-open connection actually moved to established but we were
1457 * waiting for syn retransmit to pop to call cleanup from the right
1459 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1461 if (tcp_half_open_connection_cleanup (tc))
1462 TCP_DBG ("could not remove half-open connection");
1466 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1469 /* Active open establish timeout */
1470 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1472 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
1473 tcp_connection_cleanup (tc);
1477 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1479 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1480 tcp_worker_stats_inc (wrk, no_buffer, 1);
1484 /* Try without increasing RTO a number of times. If this fails,
1485 * start growing RTO exponentially */
1487 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1488 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1490 b = vlib_get_buffer (vm, bi);
1491 tcp_init_buffer (vm, b);
1492 tcp_make_syn (tc, b);
1494 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1496 /* This goes straight to ipx_lookup */
1497 tcp_push_ip_hdr (wrk, tc, b);
1498 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1500 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1501 tc->rto * TCP_TO_TIMER_TICK);
1505 * Got 0 snd_wnd from peer, try to do something about it.
1509 tcp_timer_persist_handler (tcp_connection_t * tc)
1511 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1512 u32 bi, max_snd_bytes, available_bytes, offset;
1513 tcp_main_t *tm = vnet_get_tcp_main ();
1514 vlib_main_t *vm = wrk->vm;
1519 /* Problem already solved or worse */
1520 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1521 || (tc->flags & TCP_CONN_FINSNT))
1522 goto update_scheduler;
1524 available_bytes = transport_max_tx_dequeue (&tc->connection);
1525 offset = tc->snd_nxt - tc->snd_una;
1527 /* Reprogram persist if no new bytes available to send. We may have data
1529 if (!available_bytes)
1531 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1535 if (available_bytes <= offset)
1536 goto update_scheduler;
1538 /* Increment RTO backoff */
1540 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1543 * Try to force the first unsent segment (or buffer)
1545 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1547 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1548 tcp_worker_stats_inc (wrk, no_buffer, 1);
1552 b = vlib_get_buffer (vm, bi);
1553 data = tcp_init_buffer (vm, b);
1555 tcp_validate_txf_size (tc, offset);
1556 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1557 max_snd_bytes = clib_min (tc->snd_mss,
1558 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1559 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1561 b->current_length = n_bytes;
1562 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1563 || tc->snd_una == tc->snd_nxt
1564 || tc->rto_boff > 1));
1566 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1568 tcp_bt_check_app_limited (tc);
1569 tcp_bt_track_tx (tc, n_bytes);
1572 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1573 /* burst */ 0, /* update_snd_nxt */ 1);
1574 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
1575 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1577 /* Just sent new data, enable retransmit */
1578 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1584 if (tcp_is_descheduled (tc))
1585 transport_connection_reschedule (&tc->connection);
1589 * Retransmit first unacked segment
1592 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1594 vlib_main_t *vm = wrk->vm;
1598 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1600 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1604 bi = vlib_get_buffer_index (vm, b);
1605 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1611 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1614 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1615 vlib_main_t *vm = wrk->vm;
1616 vlib_buffer_t *b = 0;
1618 offset = tc->snd_nxt - tc->snd_una;
1619 available_wnd = tc->snd_wnd - offset;
1620 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1622 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1623 tcp_bt_check_app_limited (tc);
1625 while (n_segs < burst_size)
1627 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1631 bi = vlib_get_buffer_index (vm, b);
1632 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1633 offset += n_written;
1636 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1637 tcp_bt_track_tx (tc, n_written);
1639 tc->snd_nxt += n_written;
1647 * Estimate send space using proportional rate reduction (RFC6937)
1650 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1655 pipe = tcp_flight_size (tc);
1656 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1658 if (pipe > tc->ssthresh)
1660 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1666 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1667 space = clib_min (tc->ssthresh - pipe, limit);
1669 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1674 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1675 sack_scoreboard_t * sb)
1677 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1678 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1680 if (tcp_fastrecovery_first (tc))
1683 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1687 tcp_max_tx_deq (tcp_connection_t * tc)
1689 return (transport_max_tx_dequeue (&tc->connection)
1690 - (tc->snd_nxt - tc->snd_una));
1693 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1694 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1695 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1698 * Do retransmit with SACKs
1701 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1704 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1705 u8 snd_limited = 0, can_rescue = 0;
1706 u32 bi, max_deq, burst_bytes;
1707 sack_scoreboard_hole_t *hole;
1708 vlib_main_t *vm = wrk->vm;
1709 vlib_buffer_t *b = 0;
1710 sack_scoreboard_t *sb;
1713 ASSERT (tcp_in_cong_recovery (tc));
1715 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1716 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1719 tcp_program_retransmit (tc);
1723 if (tcp_in_recovery (tc))
1724 snd_space = tcp_available_cc_snd_space (tc);
1726 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1728 if (snd_space < tc->snd_mss)
1733 /* Check if snd_una is a lost retransmit */
1734 if (pool_elts (sb->holes)
1735 && seq_gt (sb->high_sacked, tc->snd_congestion)
1736 && tc->rxt_head != tc->snd_una
1737 && tcp_retransmit_should_retry_head (tc, sb))
1739 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1740 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1743 tcp_program_retransmit (tc);
1746 bi = vlib_get_buffer_index (vm, b);
1747 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1750 tc->rxt_head = tc->snd_una;
1751 tc->rxt_delivered += n_written;
1752 tc->prr_delivered += n_written;
1753 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1756 tcp_fastrecovery_first_off (tc);
1758 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1759 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1761 max_deq = transport_max_tx_dequeue (&tc->connection);
1762 max_deq -= tc->snd_nxt - tc->snd_una;
1764 while (snd_space > 0 && n_segs < burst_size)
1766 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1770 /* We are out of lost holes to retransmit so send some new data. */
1771 if (max_deq > tc->snd_mss)
1776 /* Make sure we don't exceed available window and leave space
1777 * for one more packet, to avoid zero window acks */
1778 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1779 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1780 snd_space = clib_min (snd_space, av_wnd);
1781 snd_space = clib_min (max_deq, snd_space);
1782 burst_size = clib_min (burst_size - n_segs,
1783 snd_space / tc->snd_mss);
1784 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1785 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1786 if (max_deq > n_segs_new * tc->snd_mss)
1787 tcp_program_retransmit (tc);
1789 n_segs += n_segs_new;
1793 if (tcp_in_recovery (tc) || !can_rescue
1794 || scoreboard_rescue_rxt_valid (sb, tc))
1797 /* If rescue rxt undefined or less than snd_una then one segment of
1798 * up to SMSS octets that MUST include the highest outstanding
1799 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1800 * RecoveryPoint. HighRxt MUST NOT be updated.
1802 hole = scoreboard_last_hole (sb);
1803 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1804 max_bytes = clib_min (max_bytes, snd_space);
1805 offset = hole->end - tc->snd_una - max_bytes;
1806 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1811 sb->rescue_rxt = tc->snd_congestion;
1812 bi = vlib_get_buffer_index (vm, b);
1813 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1818 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1819 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1823 offset = sb->high_rxt - tc->snd_una;
1824 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1826 ASSERT (n_written <= snd_space);
1828 /* Nothing left to retransmit */
1832 bi = vlib_get_buffer_index (vm, b);
1833 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1835 sb->high_rxt += n_written;
1836 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1838 snd_space -= n_written;
1843 tcp_program_retransmit (tc);
1847 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
1852 * Fast retransmit without SACK info
1855 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1858 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
1859 u32 burst_bytes, sent_bytes;
1860 vlib_main_t *vm = wrk->vm;
1861 int snd_space, n_segs = 0;
1865 ASSERT (tcp_in_cong_recovery (tc));
1866 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1868 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1869 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1872 tcp_program_retransmit (tc);
1876 snd_space = tcp_available_cc_snd_space (tc);
1877 cc_limited = snd_space < burst_bytes;
1879 if (!tcp_fastrecovery_first (tc))
1882 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1884 while (snd_space > 0 && n_segs < burst_size)
1886 max_bytes = clib_min (tc->snd_mss,
1887 tc->snd_congestion - tc->snd_una - offset);
1890 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1893 /* Nothing left to retransmit */
1897 bi = vlib_get_buffer_index (vm, b);
1898 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1899 snd_space -= n_written;
1900 offset += n_written;
1904 if (n_segs == burst_size)
1909 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1910 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1913 max_deq = transport_max_tx_dequeue (&tc->connection);
1914 max_deq -= tc->snd_nxt - tc->snd_una;
1917 snd_space = clib_min (max_deq, snd_space);
1918 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1919 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1920 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
1921 tcp_program_retransmit (tc);
1922 n_segs += n_segs_now;
1926 tcp_fastrecovery_first_off (tc);
1928 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1929 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1930 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1936 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1940 if (!tc->pending_dupacks)
1942 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1943 || tc->state != TCP_STATE_ESTABLISHED)
1951 /* If we're supposed to send dupacks but have no ooo data
1952 * send only one ack */
1953 if (!vec_len (tc->snd_sacks))
1956 tc->dupacks_out += 1;
1957 tc->pending_dupacks = 0;
1961 /* Start with first sack block */
1962 tc->snd_sack_pos = 0;
1964 /* Generate enough dupacks to cover all sack blocks. Do not generate
1965 * more sacks than the number of packets received. But do generate at
1966 * least 3, i.e., the number needed to signal congestion, if needed. */
1967 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1968 n_acks = clib_min (n_acks, tc->pending_dupacks);
1969 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1970 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1973 if (n_acks < max_burst_size)
1975 tc->pending_dupacks = 0;
1976 tc->snd_sack_pos = 0;
1977 tc->dupacks_out += n_acks;
1982 TCP_DBG ("constrained by burst size");
1983 tc->pending_dupacks = n_acks - max_burst_size;
1984 tc->dupacks_out += max_burst_size;
1985 tcp_program_dupack (tc);
1986 return max_burst_size;
1991 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
1993 tcp_worker_ctx_t *wrk;
1996 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
1999 wrk = tcp_get_worker (tc->c_thread_index);
2001 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2002 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2004 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2010 tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
2012 tcp_connection_t *tc = (tcp_connection_t *) conn;
2015 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2017 tc->flags &= ~TCP_CONN_RXT_PENDING;
2018 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
2021 if (!(tc->flags & TCP_CONN_SNDACK))
2024 tc->flags &= ~TCP_CONN_SNDACK;
2026 /* We have retransmitted packets and no dupack */
2027 if (n_segs && !tc->pending_dupacks)
2030 if (sp->max_burst_size <= n_segs)
2032 tcp_program_ack (tc);
2036 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
2040 #endif /* CLIB_MARCH_VARIANT */
2043 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2044 u16 * next0, u32 * error0)
2046 ip_adjacency_t *adj;
2049 /* Not thread safe but as long as the connection exists the adj should
2051 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2053 if (ai == ADJ_INDEX_INVALID)
2055 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2056 *next0 = TCP_OUTPUT_NEXT_DROP;
2057 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2062 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2063 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2064 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2065 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2068 *next0 = TCP_OUTPUT_NEXT_DROP;
2069 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2071 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2075 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2076 u32 * to_next, u32 n_bufs)
2078 tcp_connection_t *tc;
2084 for (i = 0; i < n_bufs; i++)
2086 b = vlib_get_buffer (vm, to_next[i]);
2087 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2089 th = vlib_buffer_get_current (b);
2090 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2092 t = vlib_add_trace (vm, node, b, sizeof (*t));
2093 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2094 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2099 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2100 tcp_connection_t * tc0, u8 is_ip4)
2102 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2103 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2104 b0->current_length);
2107 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2108 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2110 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2111 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
2115 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2117 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2120 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2122 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2123 data_len += b->total_length_not_including_first_buffer;
2125 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2129 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2130 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2131 b->flags |= VNET_BUFFER_F_GSO;
2132 vnet_buffer2 (b)->gso_l4_hdr_sz =
2133 sizeof (tcp_header_t) + tc->snd_opts_len;
2134 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2139 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2140 vlib_node_runtime_t * error_node, u16 * next0,
2143 /* If next_index is not drop use it */
2144 if (tc0->next_node_index)
2146 *next0 = tc0->next_node_index;
2147 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2151 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2154 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2155 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2161 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2162 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2164 if (PREDICT_FALSE (error0))
2166 b0->error = error_node->errors[error0];
2175 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2176 vlib_frame_t * frame, int is_ip4)
2178 u32 n_left_from, *from, thread_index = vm->thread_index;
2179 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2180 u16 nexts[VLIB_FRAME_SIZE], *next;
2182 from = vlib_frame_vector_args (frame);
2183 n_left_from = frame->n_vectors;
2184 tcp_set_time_now (tcp_get_worker (thread_index));
2186 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2187 tcp46_output_trace_frame (vm, node, from, n_left_from);
2189 vlib_get_buffers (vm, from, bufs, n_left_from);
2193 while (n_left_from >= 4)
2195 tcp_connection_t *tc0, *tc1;
2198 vlib_prefetch_buffer_header (b[2], STORE);
2199 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2201 vlib_prefetch_buffer_header (b[3], STORE);
2202 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2205 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2207 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2210 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2212 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2213 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2215 tcp_check_if_gso (tc0, b[0]);
2216 tcp_check_if_gso (tc1, b[1]);
2218 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2219 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2225 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2226 tcp_check_if_gso (tc0, b[0]);
2227 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2231 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2232 next[0] = TCP_OUTPUT_NEXT_DROP;
2236 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2237 tcp_check_if_gso (tc1, b[1]);
2238 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2242 b[1]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2243 next[1] = TCP_OUTPUT_NEXT_DROP;
2251 while (n_left_from > 0)
2253 tcp_connection_t *tc0;
2255 if (n_left_from > 1)
2257 vlib_prefetch_buffer_header (b[1], STORE);
2258 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2261 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2264 if (PREDICT_TRUE (tc0 != 0))
2266 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2267 tcp_check_if_gso (tc0, b[0]);
2268 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2272 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2273 next[0] = TCP_OUTPUT_NEXT_DROP;
2281 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2282 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2283 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2284 return frame->n_vectors;
2287 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2288 vlib_frame_t * from_frame)
2290 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2293 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2294 vlib_frame_t * from_frame)
2296 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2300 VLIB_REGISTER_NODE (tcp4_output_node) =
2302 .name = "tcp4-output",
2303 /* Takes a vector of packets. */
2304 .vector_size = sizeof (u32),
2305 .n_errors = TCP_N_ERROR,
2306 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2307 .error_strings = tcp_error_strings,
2308 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2310 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2311 foreach_tcp4_output_next
2314 .format_buffer = format_tcp_header,
2315 .format_trace = format_tcp_tx_trace,
2320 VLIB_REGISTER_NODE (tcp6_output_node) =
2322 .name = "tcp6-output",
2323 /* Takes a vector of packets. */
2324 .vector_size = sizeof (u32),
2325 .n_errors = TCP_N_ERROR,
2326 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2327 .error_strings = tcp_error_strings,
2328 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2330 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2331 foreach_tcp6_output_next
2334 .format_buffer = format_tcp_header,
2335 .format_trace = format_tcp_tx_trace,
2339 typedef enum _tcp_reset_next
2341 TCP_RESET_NEXT_DROP,
2342 TCP_RESET_NEXT_IP_LOOKUP,
2346 #define foreach_tcp4_reset_next \
2347 _(DROP, "error-drop") \
2348 _(IP_LOOKUP, "ip4-lookup")
2350 #define foreach_tcp6_reset_next \
2351 _(DROP, "error-drop") \
2352 _(IP_LOOKUP, "ip6-lookup")
2355 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2356 vlib_frame_t * from_frame, u8 is_ip4)
2358 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2359 u32 n_left_from, next_index, *from, *to_next;
2361 from = vlib_frame_vector_args (from_frame);
2362 n_left_from = from_frame->n_vectors;
2364 next_index = node->cached_next_index;
2366 while (n_left_from > 0)
2370 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2372 while (n_left_from > 0 && n_left_to_next > 0)
2384 n_left_to_next -= 1;
2386 b0 = vlib_get_buffer (vm, bi0);
2387 tcp_make_reset_in_place (vm, b0, is_ip4);
2389 /* Prepare to send to IP lookup */
2390 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2392 b0->error = node->errors[error0];
2393 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2394 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2396 th0 = vlib_buffer_get_current (b0);
2398 th0 = ip4_next_header ((ip4_header_t *) th0);
2400 th0 = ip6_next_header ((ip6_header_t *) th0);
2401 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2402 clib_memcpy_fast (&t0->tcp_header, th0,
2403 sizeof (t0->tcp_header));
2406 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2407 n_left_to_next, bi0, next0);
2409 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2411 return from_frame->n_vectors;
2414 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2415 vlib_frame_t * from_frame)
2417 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2420 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2421 vlib_frame_t * from_frame)
2423 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2427 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2428 .name = "tcp4-reset",
2429 .vector_size = sizeof (u32),
2430 .n_errors = TCP_N_ERROR,
2431 .error_strings = tcp_error_strings,
2432 .n_next_nodes = TCP_RESET_N_NEXT,
2434 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2435 foreach_tcp4_reset_next
2438 .format_trace = format_tcp_tx_trace,
2443 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2444 .name = "tcp6-reset",
2445 .vector_size = sizeof (u32),
2446 .n_errors = TCP_N_ERROR,
2447 .error_strings = tcp_error_strings,
2448 .n_next_nodes = TCP_RESET_N_NEXT,
2450 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2451 foreach_tcp6_reset_next
2454 .format_trace = format_tcp_tx_trace,
2459 * fd.io coding-style-patch-verification: ON
2462 * eval: (c-set-style "gnu")