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>
20 typedef enum _tcp_output_next
23 TCP_OUTPUT_NEXT_IP_LOOKUP,
24 TCP_OUTPUT_NEXT_IP_REWRITE,
25 TCP_OUTPUT_NEXT_IP_ARP,
29 #define foreach_tcp4_output_next \
30 _ (DROP, "error-drop") \
31 _ (IP_LOOKUP, "ip4-lookup") \
32 _ (IP_REWRITE, "ip4-rewrite") \
35 #define foreach_tcp6_output_next \
36 _ (DROP, "error-drop") \
37 _ (IP_LOOKUP, "ip6-lookup") \
38 _ (IP_REWRITE, "ip6-rewrite") \
39 _ (IP_ARP, "ip6-discover-neighbor")
41 static char *tcp_error_strings[] = {
42 #define tcp_error(n,s) s,
43 #include <vnet/tcp/tcp_error.def>
49 tcp_header_t tcp_header;
50 tcp_connection_t tcp_connection;
54 format_tcp_tx_trace (u8 * s, va_list * args)
56 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
57 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
58 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
59 tcp_connection_t *tc = &t->tcp_connection;
60 u32 indent = format_get_indent (s);
62 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
63 format_tcp_state, tc->state, format_white_space, indent,
64 format_tcp_header, &t->tcp_header, 128);
69 #ifndef CLIB_MARCH_VARIANT
71 tcp_window_compute_scale (u32 window)
74 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
80 * TCP's initial window
83 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
85 /* RFC 6928 recommends the value lower. However at the time our connections
86 * are initialized, fifos may not be allocated. Therefore, advertise the
87 * smallest possible unscaled window size and update once fifos are
88 * assigned to the session.
91 tcp_update_rcv_mss (tc);
92 TCP_IW_N_SEGMENTS * tc->mss;
94 return tcp_cfg.min_rx_fifo;
98 * Compute initial window and scale factor. As per RFC1323, window field in
99 * SYN and SYN-ACK segments is never scaled.
102 tcp_initial_window_to_advertise (tcp_connection_t * tc)
104 /* Compute rcv wscale only if peer advertised support for it */
105 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
106 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
108 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
110 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
114 tcp_update_rcv_wnd (tcp_connection_t * tc)
116 u32 available_space, wnd;
120 * Figure out how much space we have available
122 available_space = transport_max_rx_enqueue (&tc->connection);
125 * Use the above and what we know about what we've previously advertised
126 * to compute the new window
128 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
130 /* Check if we are about to retract the window. Do the comparison before
131 * rounding to avoid errors. Per RFC7323 sec. 2.4 we could remove this */
132 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
134 wnd = round_down_pow2 (clib_max (observed_wnd, 0), 1 << tc->rcv_wscale);
135 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
139 /* Make sure we have a multiple of 1 << rcv_wscale. We round down to
140 * avoid advertising a window larger than what can be buffered */
141 wnd = round_down_pow2 (available_space, 1 << tc->rcv_wscale);
144 if (PREDICT_FALSE (wnd < tc->rcv_opts.mss))
147 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
151 * Compute and return window to advertise, scaled as per RFC1323
154 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
156 if (state < TCP_STATE_ESTABLISHED)
157 return tcp_initial_window_to_advertise (tc);
159 tcp_update_rcv_wnd (tc);
160 return tc->rcv_wnd >> tc->rcv_wscale;
164 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
168 opts->flags |= TCP_OPTS_FLAG_MSS;
170 len += TCP_OPTION_LEN_MSS;
172 opts->flags |= TCP_OPTS_FLAG_WSCALE;
173 opts->wscale = tc->rcv_wscale;
174 len += TCP_OPTION_LEN_WINDOW_SCALE;
176 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
177 opts->tsval = tcp_time_now ();
179 len += TCP_OPTION_LEN_TIMESTAMP;
183 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
184 len += TCP_OPTION_LEN_SACK_PERMITTED;
187 /* Align to needed boundary */
188 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
193 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
197 opts->flags |= TCP_OPTS_FLAG_MSS;
199 len += TCP_OPTION_LEN_MSS;
201 if (tcp_opts_wscale (&tc->rcv_opts))
203 opts->flags |= TCP_OPTS_FLAG_WSCALE;
204 opts->wscale = tc->rcv_wscale;
205 len += TCP_OPTION_LEN_WINDOW_SCALE;
208 if (tcp_opts_tstamp (&tc->rcv_opts))
210 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
211 opts->tsval = tcp_time_now ();
212 opts->tsecr = tc->tsval_recent;
213 len += TCP_OPTION_LEN_TIMESTAMP;
216 if (tcp_opts_sack_permitted (&tc->rcv_opts))
218 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
219 len += TCP_OPTION_LEN_SACK_PERMITTED;
222 /* Align to needed boundary */
223 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
228 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
234 if (tcp_opts_tstamp (&tc->rcv_opts))
236 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
237 opts->tsval = tcp_tstamp (tc);
238 opts->tsecr = tc->tsval_recent;
239 len += TCP_OPTION_LEN_TIMESTAMP;
241 if (tcp_opts_sack_permitted (&tc->rcv_opts))
243 if (vec_len (tc->snd_sacks))
245 opts->flags |= TCP_OPTS_FLAG_SACK;
246 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
247 tc->snd_sack_pos = 0;
248 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
249 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
250 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
251 TCP_OPTS_MAX_SACK_BLOCKS);
252 tc->snd_sack_pos += opts->n_sack_blocks;
253 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
257 /* Align to needed boundary */
258 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
263 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
268 case TCP_STATE_ESTABLISHED:
269 case TCP_STATE_CLOSE_WAIT:
270 case TCP_STATE_FIN_WAIT_1:
271 case TCP_STATE_LAST_ACK:
272 case TCP_STATE_CLOSING:
273 case TCP_STATE_FIN_WAIT_2:
274 case TCP_STATE_TIME_WAIT:
275 case TCP_STATE_CLOSED:
276 return tcp_make_established_options (tc, opts);
277 case TCP_STATE_SYN_RCVD:
278 return tcp_make_synack_options (tc, opts);
279 case TCP_STATE_SYN_SENT:
280 return tcp_make_syn_options (tc, opts);
282 clib_warning ("State not handled! %d", state);
288 * Update burst send vars
290 * - Updates snd_mss to reflect the effective segment size that we can send
291 * by taking into account all TCP options, including SACKs.
292 * - Cache 'on the wire' options for reuse
293 * - Updates receive window which can be reused for a burst.
295 * This should *only* be called when doing bursts
298 tcp_update_burst_snd_vars (tcp_connection_t * tc)
300 tcp_main_t *tm = &tcp_main;
302 /* Compute options to be used for connection. These may be reused when
303 * sending data or to compute the effective mss (snd_mss) */
304 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
305 TCP_STATE_ESTABLISHED);
307 /* XXX check if MTU has been updated */
308 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
309 ASSERT (tc->snd_mss > 0);
311 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
314 tcp_update_rcv_wnd (tc);
316 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
317 tcp_bt_check_app_limited (tc);
319 if (tc->snd_una == tc->snd_nxt)
321 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
322 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST);
326 #endif /* CLIB_MARCH_VARIANT */
329 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
331 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
332 vlib_buffer_free_one (vm, b->next_buffer);
333 /* Zero all flags but free list index and trace flag */
334 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
336 b->current_length = 0;
337 b->total_length_not_including_first_buffer = 0;
338 vnet_buffer (b)->tcp.flags = 0;
340 /* Leave enough space for headers */
341 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
344 #ifndef CLIB_MARCH_VARIANT
346 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
348 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
349 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
350 b->total_length_not_including_first_buffer = 0;
352 vnet_buffer (b)->tcp.flags = 0;
353 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
354 /* Leave enough space for headers */
355 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
359 /* Compute TCP checksum in software when offloading is disabled for a connection */
361 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
362 ip46_address_t * src, ip46_address_t * dst)
365 u16 payload_length_host_byte_order;
368 /* Initialize checksum with ip header. */
369 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
370 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
371 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
373 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
375 sum0 = ip_csum_with_carry
376 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
377 sum0 = ip_csum_with_carry
378 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
381 return ip_calculate_l4_checksum (vm, p0, sum0,
382 payload_length_host_byte_order, NULL, 0,
387 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
388 ip46_address_t * src, ip46_address_t * dst)
391 u32 payload_length_host_byte_order;
393 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
395 clib_host_to_net_u32 (payload_length_host_byte_order +
396 (IP_PROTOCOL_TCP << 16));
398 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
399 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
401 return ip_calculate_l4_checksum (vm, p0, sum0,
402 payload_length_host_byte_order, NULL, 0,
407 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
410 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
412 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
413 vlib_main_t *vm = wrk->vm;
416 checksum = ip4_tcp_compute_checksum_custom
417 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
419 checksum = ip6_tcp_compute_checksum_custom
420 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
424 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
433 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
436 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
437 u8 tcp_opts_len, tcp_hdr_opts_len;
441 wnd = tcp_window_to_advertise (tc, state);
443 /* Make and write options */
444 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
445 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
447 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
448 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
450 tcp_options_write ((u8 *) (th + 1), snd_opts);
452 th->checksum = tcp_compute_checksum (tc, b);
454 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
457 tcp_zero_rwnd_sent_on (tc);
459 tcp_zero_rwnd_sent_off (tc);
463 * Convert buffer to ACK
466 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
468 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
469 TCP_EVT (TCP_EVT_ACK_SENT, tc);
470 tc->rcv_las = tc->rcv_nxt;
474 * Convert buffer to FIN-ACK
477 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
479 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
483 * Convert buffer to SYN
486 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
488 u8 tcp_hdr_opts_len, tcp_opts_len;
491 tcp_options_t snd_opts;
493 initial_wnd = tcp_initial_window_to_advertise (tc);
495 /* Make and write options */
496 clib_memset (&snd_opts, 0, sizeof (snd_opts));
497 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
498 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
500 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
501 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
503 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
504 tcp_options_write ((u8 *) (th + 1), &snd_opts);
505 th->checksum = tcp_compute_checksum (tc, b);
509 * Convert buffer to SYN-ACK
512 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
514 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
515 u8 tcp_opts_len, tcp_hdr_opts_len;
519 clib_memset (snd_opts, 0, sizeof (*snd_opts));
520 initial_wnd = tcp_initial_window_to_advertise (tc);
521 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
522 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
524 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
525 tc->rcv_nxt, tcp_hdr_opts_len,
526 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
527 tcp_options_write ((u8 *) (th + 1), snd_opts);
529 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
530 th->checksum = tcp_compute_checksum (tc, b);
534 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
535 u8 is_ip4, u32 fib_index)
537 tcp_main_t *tm = &tcp_main;
538 vlib_main_t *vm = wrk->vm;
540 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
543 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
544 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
546 tcp_trajectory_add_start (b, 1);
548 session_add_pending_tx_buffer (vm->thread_index, bi,
549 tm->ipl_next_node[!is_ip4]);
551 if (vm->thread_index == 0 && vlib_num_workers ())
552 session_queue_run_on_main_thread (wrk->vm);
556 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
559 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
562 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
563 wrk->tco_next_node[!is_ip4]);
566 #endif /* CLIB_MARCH_VARIANT */
569 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b, u8 is_ip4)
574 ip4_address_t src_ip4, dst_ip4;
575 ip6_address_t src_ip6, dst_ip6;
576 u16 src_port, dst_port;
577 u32 tmp, len, seq, ack;
580 /* Find IP and TCP headers */
581 th = tcp_buffer_hdr (b);
583 /* Save src and dst ip */
586 ih4 = vlib_buffer_get_current (b);
587 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
588 src_ip4.as_u32 = ih4->src_address.as_u32;
589 dst_ip4.as_u32 = ih4->dst_address.as_u32;
593 ih6 = vlib_buffer_get_current (b);
594 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
595 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
596 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
599 src_port = th->src_port;
600 dst_port = th->dst_port;
601 flags = TCP_FLAG_RST;
604 * RFC 793. If the ACK bit is off, sequence number zero is used,
605 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
606 * If the ACK bit is on,
607 * <SEQ=SEG.ACK><CTL=RST>
611 seq = th->ack_number;
616 flags |= TCP_FLAG_ACK;
617 tmp = clib_net_to_host_u32 (th->seq_number);
618 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
619 ack = clib_host_to_net_u32 (tmp + len);
623 tcp_reuse_buffer (vm, b);
624 tcp_trajectory_add_start (b, 4);
625 th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack,
626 sizeof (tcp_header_t), flags, 0);
630 ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4,
632 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
637 ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP);
638 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
645 #ifndef CLIB_MARCH_VARIANT
647 * Send reset without reusing existing buffer
649 * It extracts connection info out of original packet
652 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
653 u32 thread_index, u8 is_ip4)
655 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
656 vlib_main_t *vm = wrk->vm;
658 u32 bi, sw_if_index, fib_index;
659 u8 tcp_hdr_len, flags = 0;
660 tcp_header_t *th, *pkt_th;
662 ip4_header_t *ih4, *pkt_ih4;
663 ip6_header_t *ih6, *pkt_ih6;
664 fib_protocol_t fib_proto;
666 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
668 tcp_worker_stats_inc (wrk, no_buffer, 1);
672 b = vlib_get_buffer (vm, bi);
673 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
674 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
675 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
676 tcp_init_buffer (vm, b);
678 /* Make and write options */
679 tcp_hdr_len = sizeof (tcp_header_t);
683 pkt_ih4 = vlib_buffer_get_current (pkt);
684 pkt_th = ip4_next_header (pkt_ih4);
688 pkt_ih6 = vlib_buffer_get_current (pkt);
689 pkt_th = ip6_next_header (pkt_ih6);
692 if (tcp_ack (pkt_th))
694 flags = TCP_FLAG_RST;
695 seq = pkt_th->ack_number;
696 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
700 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
702 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
705 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
706 seq, ack, tcp_hdr_len, flags, 0);
708 /* Swap src and dst ip */
711 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
712 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
713 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
714 tcp_csum_offload (tc));
715 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
720 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
722 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
723 &pkt_ih6->src_address,
725 tc->ipv6_flow_label);
726 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
730 tcp_enqueue_to_ip_lookup (wrk, b, bi, is_ip4, fib_index);
731 TCP_EVT (TCP_EVT_RST_SENT, tc);
732 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
733 TCP_ERROR_RST_SENT, 1);
737 * Build and set reset packet for connection
740 tcp_send_reset (tcp_connection_t * tc)
742 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
743 vlib_main_t *vm = wrk->vm;
747 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
750 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
752 tcp_worker_stats_inc (wrk, no_buffer, 1);
755 b = vlib_get_buffer (vm, bi);
756 tcp_init_buffer (vm, b);
758 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
759 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
760 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
761 flags = TCP_FLAG_RST;
762 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
763 tc->rcv_nxt, tcp_hdr_opts_len, flags,
765 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
766 th->checksum = tcp_compute_checksum (tc, b);
767 ASSERT (opts_write_len == tc->snd_opts_len);
768 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
769 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
770 TCP_EVT (TCP_EVT_RST_SENT, tc);
771 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
772 TCP_ERROR_RST_SENT, 1);
776 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
781 vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4,
782 IP_PROTOCOL_TCP, tcp_csum_offload (tc));
786 vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6,
787 IP_PROTOCOL_TCP, tc->ipv6_flow_label);
794 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
795 * The packet is not forwarded through tcpx_output to avoid doing lookups
796 * in the half_open pool.
799 tcp_send_syn (tcp_connection_t * tc)
801 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
802 vlib_main_t *vm = wrk->vm;
807 * Setup retransmit and establish timers before requesting buffer
808 * such that we can return if we've ran out.
810 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
811 tc->rto * TCP_TO_TIMER_TICK);
813 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
815 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
816 tcp_worker_stats_inc (wrk, no_buffer, 1);
820 b = vlib_get_buffer (vm, bi);
821 tcp_init_buffer (vm, b);
822 tcp_make_syn (tc, b);
824 /* Measure RTT with this */
825 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
826 tc->rtt_seq = tc->snd_nxt;
829 tcp_push_ip_hdr (wrk, tc, b);
830 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
831 TCP_EVT (TCP_EVT_SYN_SENT, tc);
835 tcp_send_synack (tcp_connection_t * tc)
837 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
838 vlib_main_t *vm = wrk->vm;
842 ASSERT (tc->snd_una != tc->snd_nxt);
843 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
845 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
847 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
848 tcp_worker_stats_inc (wrk, no_buffer, 1);
852 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
853 b = vlib_get_buffer (vm, bi);
854 tcp_init_buffer (vm, b);
855 tcp_make_synack (tc, b);
856 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
857 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
864 tcp_send_fin (tcp_connection_t * tc)
866 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
867 vlib_main_t *vm = wrk->vm;
872 fin_snt = tc->flags & TCP_CONN_FINSNT;
876 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
878 /* Out of buffers so program fin retransmit ASAP */
879 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
883 /* Make sure retransmit retries a fin not data */
884 tc->flags |= TCP_CONN_FINSNT;
885 tcp_worker_stats_inc (wrk, no_buffer, 1);
889 /* If we have non-dupacks programmed, no need to send them */
890 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
891 tc->flags &= ~TCP_CONN_SNDACK;
893 b = vlib_get_buffer (vm, bi);
894 tcp_init_buffer (vm, b);
895 tcp_make_fin (tc, b);
896 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
897 TCP_EVT (TCP_EVT_FIN_SENT, tc);
898 /* Account for the FIN */
900 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
903 tc->flags |= TCP_CONN_FINSNT;
904 tc->flags &= ~TCP_CONN_FINPNDG;
909 * Push TCP header and update connection variables. Should only be called
910 * for segments with data, not for 'control' packets.
913 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
914 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
916 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
917 u32 advertise_wnd, data_len;
918 tcp_main_t *tm = &tcp_main;
921 data_len = b->current_length;
922 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
923 data_len += b->total_length_not_including_first_buffer;
925 vnet_buffer (b)->tcp.flags = 0;
926 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
929 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
931 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
934 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
936 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
938 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
940 if (seq_geq (tc->psh_seq, snd_nxt)
941 && seq_lt (tc->psh_seq, snd_nxt + data_len))
942 flags |= TCP_FLAG_PSH;
944 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
945 tc->rcv_nxt, tcp_hdr_opts_len, flags,
950 clib_memcpy_fast ((u8 *) (th + 1),
951 tm->wrk_ctx[tc->c_thread_index].cached_opts,
956 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
957 ASSERT (len == tc->snd_opts_len);
961 * Update connection variables
965 tc->snd_nxt += data_len;
966 tc->rcv_las = tc->rcv_nxt;
968 tc->bytes_out += data_len;
969 tc->data_segs_out += 1;
971 th->checksum = tcp_compute_checksum (tc, b);
973 TCP_EVT (TCP_EVT_PKTIZE, tc);
977 tcp_buffer_len (vlib_buffer_t * b)
979 u32 data_len = b->current_length;
980 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
981 data_len += b->total_length_not_including_first_buffer;
986 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
988 tcp_connection_t *tc = (tcp_connection_t *) tconn;
990 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
991 tcp_bt_track_tx (tc, tcp_buffer_len (b));
993 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
994 /* update_snd_nxt */ 1);
996 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
997 /* If not tracking an ACK, start tracking */
998 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1000 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1001 tc->rtt_seq = tc->snd_nxt;
1003 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1005 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1006 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
1009 tcp_trajectory_add_start (b, 3);
1014 tcp_send_ack (tcp_connection_t * tc)
1016 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1017 vlib_main_t *vm = wrk->vm;
1021 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1023 tcp_update_rcv_wnd (tc);
1024 tcp_worker_stats_inc (wrk, no_buffer, 1);
1027 b = vlib_get_buffer (vm, bi);
1028 tcp_init_buffer (vm, b);
1029 tcp_make_ack (tc, b);
1030 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1034 tcp_program_ack (tcp_connection_t * tc)
1036 if (!(tc->flags & TCP_CONN_SNDACK))
1038 session_add_self_custom_tx_evt (&tc->connection, 1);
1039 tc->flags |= TCP_CONN_SNDACK;
1044 tcp_program_dupack (tcp_connection_t * tc)
1046 if (!(tc->flags & TCP_CONN_SNDACK))
1048 session_add_self_custom_tx_evt (&tc->connection, 1);
1049 tc->flags |= TCP_CONN_SNDACK;
1051 if (tc->pending_dupacks < 255)
1052 tc->pending_dupacks += 1;
1056 tcp_program_retransmit (tcp_connection_t * tc)
1058 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1060 session_add_self_custom_tx_evt (&tc->connection, 0);
1061 tc->flags |= TCP_CONN_RXT_PENDING;
1066 * Send window update ack
1068 * Ensures that it will be sent only once, after a zero rwnd has been
1069 * advertised in a previous ack, and only if rwnd has grown beyond a
1070 * configurable value.
1073 tcp_send_window_update_ack (tcp_connection_t * tc)
1075 if (tcp_zero_rwnd_sent (tc))
1077 tcp_update_rcv_wnd (tc);
1078 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1080 tcp_zero_rwnd_sent_off (tc);
1081 tcp_program_ack (tc);
1087 * Allocate a new buffer and build a new tcp segment
1089 * @param wrk tcp worker
1090 * @param tc connection for which the segment will be allocated
1091 * @param offset offset of the first byte in the tx fifo
1092 * @param max_deq_byte segment size
1093 * @param[out] b pointer to buffer allocated
1095 * @return the number of bytes in the segment or 0 if buffer cannot be
1096 * allocated or no data available
1099 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1100 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1102 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1103 vlib_main_t *vm = wrk->vm;
1108 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1113 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1116 * Allocate and fill in buffer(s)
1119 /* Easy case, buffer size greater than mss */
1120 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1122 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1124 tcp_worker_stats_inc (wrk, no_buffer, 1);
1127 *b = vlib_get_buffer (vm, bi);
1128 data = tcp_init_buffer (vm, *b);
1129 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1131 ASSERT (n_bytes == max_deq_bytes);
1132 b[0]->current_length = n_bytes;
1133 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1134 /* burst */ 0, /* update_snd_nxt */ 0);
1136 /* Split mss into multiple buffers */
1139 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1140 u16 n_peeked, len_to_deq;
1141 vlib_buffer_t *chain_b, *prev_b;
1144 /* Make sure we have enough buffers */
1145 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1146 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1147 CLIB_CACHE_LINE_BYTES);
1148 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1149 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1152 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1153 tcp_worker_stats_inc (wrk, no_buffer, 1);
1157 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1158 data = tcp_init_buffer (vm, *b);
1159 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1161 TRANSPORT_MAX_HDRS_LEN);
1162 b[0]->current_length = n_bytes;
1163 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1164 b[0]->total_length_not_including_first_buffer = 0;
1165 max_deq_bytes -= n_bytes;
1168 for (i = 1; i < n_bufs_per_seg; i++)
1171 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1172 chain_bi = wrk->tx_buffers[--n_bufs];
1173 chain_b = vlib_get_buffer (vm, chain_bi);
1174 chain_b->current_data = 0;
1175 data = vlib_buffer_get_current (chain_b);
1176 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1179 ASSERT (n_peeked == len_to_deq);
1180 n_bytes += n_peeked;
1181 chain_b->current_length = n_peeked;
1182 chain_b->next_buffer = 0;
1184 /* update previous buffer */
1185 prev_b->next_buffer = chain_bi;
1186 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1188 max_deq_bytes -= n_peeked;
1189 b[0]->total_length_not_including_first_buffer += n_peeked;
1192 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1193 /* burst */ 0, /* update_snd_nxt */ 0);
1195 if (PREDICT_FALSE (n_bufs))
1197 clib_warning ("not all buffers consumed");
1198 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1202 ASSERT (n_bytes > 0);
1203 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1209 * Build a retransmit segment
1211 * @return the number of bytes in the segment or 0 if there's nothing to
1215 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1216 tcp_connection_t * tc, u32 offset,
1217 u32 max_deq_bytes, vlib_buffer_t ** b)
1219 u32 start, available_bytes;
1222 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1223 ASSERT (max_deq_bytes != 0);
1226 * Make sure we can retransmit something
1228 available_bytes = transport_max_tx_dequeue (&tc->connection);
1229 ASSERT (available_bytes >= offset);
1230 available_bytes -= offset;
1231 if (!available_bytes)
1234 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1235 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1237 start = tc->snd_una + offset;
1238 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1240 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1244 tc->snd_rxt_bytes += n_bytes;
1246 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1247 tcp_bt_track_rxt (tc, start, start + n_bytes);
1249 tc->bytes_retrans += n_bytes;
1250 tc->segs_retrans += 1;
1251 tcp_worker_stats_inc (wrk, rxt_segs, 1);
1252 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1258 tcp_check_sack_reneging (tcp_connection_t * tc)
1260 sack_scoreboard_t *sb = &tc->sack_sb;
1261 sack_scoreboard_hole_t *hole;
1263 hole = scoreboard_first_hole (sb);
1264 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1267 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1271 * Reset congestion control, switch cwnd to loss window and try again.
1274 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1276 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1278 tc->prev_ssthresh = tc->ssthresh;
1279 tc->prev_cwnd = tc->cwnd;
1281 /* If we entrered loss without fast recovery, notify cc algo of the
1282 * congestion event such that it can update ssthresh and its state */
1283 if (!tcp_in_fastrecovery (tc))
1284 tcp_cc_congestion (tc);
1286 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1290 tc->cwnd_acc_bytes = 0;
1291 tc->tr_occurences += 1;
1292 tc->sack_sb.reorder = TCP_DUPACK_THRESHOLD;
1293 tcp_recovery_on (tc);
1297 tcp_timer_retransmit_handler (tcp_connection_t * tc)
1299 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1300 vlib_main_t *vm = wrk->vm;
1301 vlib_buffer_t *b = 0;
1304 tcp_worker_stats_inc (wrk, tr_events, 1);
1306 /* Should be handled by a different handler */
1307 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
1310 /* Wait-close and retransmit could pop at the same time */
1311 if (tc->state == TCP_STATE_CLOSED)
1314 if (tc->state >= TCP_STATE_ESTABLISHED)
1316 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1318 /* Lost FIN, retransmit and return */
1319 if (tc->flags & TCP_CONN_FINSNT)
1323 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1327 /* Shouldn't be here */
1328 if (tc->snd_una == tc->snd_nxt)
1330 ASSERT (!tcp_in_recovery (tc));
1335 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1336 * to persist timer timeout */
1337 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1340 tcp_update_rto (tc);
1343 /* Peer is dead or network connectivity is lost. Close connection.
1344 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1345 * a min rto of 0.2s we need to retry about 8 times. */
1346 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1348 tcp_send_reset (tc);
1349 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1350 session_transport_closing_notify (&tc->connection);
1351 session_transport_closed_notify (&tc->connection);
1352 tcp_connection_timers_reset (tc);
1353 tcp_program_cleanup (wrk, tc);
1354 tcp_worker_stats_inc (wrk, tr_abort, 1);
1358 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1359 tcp_check_sack_reneging (tc);
1361 /* Update send congestion to make sure that rxt has data to send */
1362 tc->snd_congestion = tc->snd_nxt;
1364 /* Send the first unacked segment. If we're short on buffers, return
1365 * as soon as possible */
1366 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1367 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1370 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1374 bi = vlib_get_buffer_index (vm, b);
1375 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1377 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1378 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1381 if (tc->rto_boff == 1)
1383 tcp_cc_init_rxt_timeout (tc);
1384 /* Record timestamp. Eifel detection algorithm RFC3522 */
1385 tc->snd_rxt_ts = tcp_tstamp (tc);
1388 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1389 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1391 tcp_program_retransmit (tc);
1393 /* Retransmit SYN-ACK */
1394 else if (tc->state == TCP_STATE_SYN_RCVD)
1396 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1400 /* Passive open establish timeout */
1401 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1403 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1404 tcp_connection_timers_reset (tc);
1405 tcp_program_cleanup (wrk, tc);
1406 tcp_worker_stats_inc (wrk, tr_abort, 1);
1410 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1412 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1413 tcp_worker_stats_inc (wrk, no_buffer, 1);
1418 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1419 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1421 ASSERT (tc->snd_una != tc->snd_nxt);
1422 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1424 b = vlib_get_buffer (vm, bi);
1425 tcp_init_buffer (vm, b);
1426 tcp_make_synack (tc, b);
1427 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1429 /* Retransmit timer already updated, just enqueue to output */
1430 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1434 ASSERT (tc->state == TCP_STATE_CLOSED);
1440 * SYN retransmit timer handler. Active open only.
1443 tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
1445 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1446 vlib_main_t *vm = wrk->vm;
1447 vlib_buffer_t *b = 0;
1450 /* Note: the connection may have transitioned to ESTABLISHED... */
1451 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
1454 /* Half-open connection actually moved to established but we were
1455 * waiting for syn retransmit to pop to call cleanup from the right
1457 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1459 if (tcp_half_open_connection_cleanup (tc))
1460 TCP_DBG ("could not remove half-open connection");
1464 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1467 /* Active open establish timeout */
1468 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1470 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
1471 tcp_connection_cleanup (tc);
1475 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1477 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1478 tcp_worker_stats_inc (wrk, no_buffer, 1);
1482 /* Try without increasing RTO a number of times. If this fails,
1483 * start growing RTO exponentially */
1485 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1486 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1488 b = vlib_get_buffer (vm, bi);
1489 tcp_init_buffer (vm, b);
1490 tcp_make_syn (tc, b);
1492 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1494 /* This goes straight to ipx_lookup */
1495 tcp_push_ip_hdr (wrk, tc, b);
1496 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1498 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1499 tc->rto * TCP_TO_TIMER_TICK);
1503 * Got 0 snd_wnd from peer, try to do something about it.
1507 tcp_timer_persist_handler (tcp_connection_t * tc)
1509 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1510 u32 bi, max_snd_bytes, available_bytes, offset;
1511 tcp_main_t *tm = vnet_get_tcp_main ();
1512 vlib_main_t *vm = wrk->vm;
1517 /* Problem already solved or worse */
1518 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1519 || (tc->flags & TCP_CONN_FINSNT))
1520 goto update_scheduler;
1522 available_bytes = transport_max_tx_dequeue (&tc->connection);
1523 offset = tc->snd_nxt - tc->snd_una;
1525 /* Reprogram persist if no new bytes available to send. We may have data
1527 if (!available_bytes)
1529 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1533 if (available_bytes <= offset)
1534 goto update_scheduler;
1536 /* Increment RTO backoff */
1538 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1541 * Try to force the first unsent segment (or buffer)
1543 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1545 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1546 tcp_worker_stats_inc (wrk, no_buffer, 1);
1550 b = vlib_get_buffer (vm, bi);
1551 data = tcp_init_buffer (vm, b);
1553 tcp_validate_txf_size (tc, offset);
1554 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1555 max_snd_bytes = clib_min (tc->snd_mss,
1556 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1557 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1559 b->current_length = n_bytes;
1560 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1561 || tc->snd_una == tc->snd_nxt
1562 || tc->rto_boff > 1));
1564 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1566 tcp_bt_check_app_limited (tc);
1567 tcp_bt_track_tx (tc, n_bytes);
1570 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1571 /* burst */ 0, /* update_snd_nxt */ 1);
1572 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
1573 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1575 /* Just sent new data, enable retransmit */
1576 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1582 if (tcp_is_descheduled (tc))
1583 transport_connection_reschedule (&tc->connection);
1587 * Retransmit first unacked segment
1590 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1592 vlib_main_t *vm = wrk->vm;
1596 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1598 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1602 bi = vlib_get_buffer_index (vm, b);
1603 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1609 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1612 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1613 vlib_main_t *vm = wrk->vm;
1614 vlib_buffer_t *b = 0;
1616 offset = tc->snd_nxt - tc->snd_una;
1617 available_wnd = tc->snd_wnd - offset;
1618 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1620 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1621 tcp_bt_check_app_limited (tc);
1623 while (n_segs < burst_size)
1625 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1629 bi = vlib_get_buffer_index (vm, b);
1630 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1631 offset += n_written;
1634 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1635 tcp_bt_track_tx (tc, n_written);
1637 tc->snd_nxt += n_written;
1645 * Estimate send space using proportional rate reduction (RFC6937)
1648 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1653 pipe = tcp_flight_size (tc);
1654 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1656 if (pipe > tc->ssthresh)
1658 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1664 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1665 space = clib_min (tc->ssthresh - pipe, limit);
1667 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1672 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1673 sack_scoreboard_t * sb)
1675 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1676 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1678 if (tcp_fastrecovery_first (tc))
1681 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1685 tcp_max_tx_deq (tcp_connection_t * tc)
1687 return (transport_max_tx_dequeue (&tc->connection)
1688 - (tc->snd_nxt - tc->snd_una));
1691 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1692 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1693 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1696 * Do retransmit with SACKs
1699 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1702 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1703 u8 snd_limited = 0, can_rescue = 0;
1704 u32 bi, max_deq, burst_bytes;
1705 sack_scoreboard_hole_t *hole;
1706 vlib_main_t *vm = wrk->vm;
1707 vlib_buffer_t *b = 0;
1708 sack_scoreboard_t *sb;
1711 ASSERT (tcp_in_cong_recovery (tc));
1713 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1714 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1717 tcp_program_retransmit (tc);
1721 if (tcp_in_recovery (tc))
1722 snd_space = tcp_available_cc_snd_space (tc);
1724 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1726 if (snd_space < tc->snd_mss)
1731 /* Check if snd_una is a lost retransmit */
1732 if (pool_elts (sb->holes)
1733 && seq_gt (sb->high_sacked, tc->snd_congestion)
1734 && tc->rxt_head != tc->snd_una
1735 && tcp_retransmit_should_retry_head (tc, sb))
1737 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1738 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1741 tcp_program_retransmit (tc);
1744 bi = vlib_get_buffer_index (vm, b);
1745 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1748 tc->rxt_head = tc->snd_una;
1749 tc->rxt_delivered += n_written;
1750 tc->prr_delivered += n_written;
1751 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1754 tcp_fastrecovery_first_off (tc);
1756 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1757 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1759 max_deq = transport_max_tx_dequeue (&tc->connection);
1760 max_deq -= tc->snd_nxt - tc->snd_una;
1762 while (snd_space > 0 && n_segs < burst_size)
1764 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1768 /* We are out of lost holes to retransmit so send some new data. */
1769 if (max_deq > tc->snd_mss)
1774 /* Make sure we don't exceed available window and leave space
1775 * for one more packet, to avoid zero window acks */
1776 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1777 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1778 snd_space = clib_min (snd_space, av_wnd);
1779 snd_space = clib_min (max_deq, snd_space);
1780 burst_size = clib_min (burst_size - n_segs,
1781 snd_space / tc->snd_mss);
1782 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1783 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1784 if (max_deq > n_segs_new * tc->snd_mss)
1785 tcp_program_retransmit (tc);
1787 n_segs += n_segs_new;
1791 if (tcp_in_recovery (tc) || !can_rescue
1792 || scoreboard_rescue_rxt_valid (sb, tc))
1795 /* If rescue rxt undefined or less than snd_una then one segment of
1796 * up to SMSS octets that MUST include the highest outstanding
1797 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1798 * RecoveryPoint. HighRxt MUST NOT be updated.
1800 hole = scoreboard_last_hole (sb);
1801 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1802 max_bytes = clib_min (max_bytes, snd_space);
1803 offset = hole->end - tc->snd_una - max_bytes;
1804 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1809 sb->rescue_rxt = tc->snd_congestion;
1810 bi = vlib_get_buffer_index (vm, b);
1811 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1816 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1817 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1821 offset = sb->high_rxt - tc->snd_una;
1822 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1824 ASSERT (n_written <= snd_space);
1826 /* Nothing left to retransmit */
1830 bi = vlib_get_buffer_index (vm, b);
1831 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1833 sb->high_rxt += n_written;
1834 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1836 snd_space -= n_written;
1841 tcp_program_retransmit (tc);
1845 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
1850 * Fast retransmit without SACK info
1853 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1856 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
1857 u32 burst_bytes, sent_bytes;
1858 vlib_main_t *vm = wrk->vm;
1859 int snd_space, n_segs = 0;
1863 ASSERT (tcp_in_cong_recovery (tc));
1864 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1866 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1867 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1870 tcp_program_retransmit (tc);
1874 snd_space = tcp_available_cc_snd_space (tc);
1875 cc_limited = snd_space < burst_bytes;
1877 if (!tcp_fastrecovery_first (tc))
1880 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1882 while (snd_space > 0 && n_segs < burst_size)
1884 max_bytes = clib_min (tc->snd_mss,
1885 tc->snd_congestion - tc->snd_una - offset);
1888 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1891 /* Nothing left to retransmit */
1895 bi = vlib_get_buffer_index (vm, b);
1896 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1897 snd_space -= n_written;
1898 offset += n_written;
1902 if (n_segs == burst_size)
1907 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1908 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1911 max_deq = transport_max_tx_dequeue (&tc->connection);
1912 max_deq -= tc->snd_nxt - tc->snd_una;
1915 snd_space = clib_min (max_deq, snd_space);
1916 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1917 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1918 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
1919 tcp_program_retransmit (tc);
1920 n_segs += n_segs_now;
1924 tcp_fastrecovery_first_off (tc);
1926 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1927 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1928 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1934 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1938 if (!tc->pending_dupacks)
1940 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1941 || tc->state != TCP_STATE_ESTABLISHED)
1949 /* If we're supposed to send dupacks but have no ooo data
1950 * send only one ack */
1951 if (!vec_len (tc->snd_sacks))
1954 tc->dupacks_out += 1;
1955 tc->pending_dupacks = 0;
1959 /* Start with first sack block */
1960 tc->snd_sack_pos = 0;
1962 /* Generate enough dupacks to cover all sack blocks. Do not generate
1963 * more sacks than the number of packets received. But do generate at
1964 * least 3, i.e., the number needed to signal congestion, if needed. */
1965 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1966 n_acks = clib_min (n_acks, tc->pending_dupacks);
1967 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1968 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1971 if (n_acks < max_burst_size)
1973 tc->pending_dupacks = 0;
1974 tc->snd_sack_pos = 0;
1975 tc->dupacks_out += n_acks;
1980 TCP_DBG ("constrained by burst size");
1981 tc->pending_dupacks = n_acks - max_burst_size;
1982 tc->dupacks_out += max_burst_size;
1983 tcp_program_dupack (tc);
1984 return max_burst_size;
1989 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
1991 tcp_worker_ctx_t *wrk;
1994 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
1997 wrk = tcp_get_worker (tc->c_thread_index);
1999 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2000 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2002 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2008 tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
2010 tcp_connection_t *tc = (tcp_connection_t *) conn;
2013 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2015 tc->flags &= ~TCP_CONN_RXT_PENDING;
2016 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
2019 if (!(tc->flags & TCP_CONN_SNDACK))
2022 tc->flags &= ~TCP_CONN_SNDACK;
2024 /* We have retransmitted packets and no dupack */
2025 if (n_segs && !tc->pending_dupacks)
2028 if (sp->max_burst_size <= n_segs)
2030 tcp_program_ack (tc);
2034 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
2038 #endif /* CLIB_MARCH_VARIANT */
2041 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2042 u16 * next0, u32 * error0)
2044 ip_adjacency_t *adj;
2047 /* Not thread safe but as long as the connection exists the adj should
2049 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2051 if (ai == ADJ_INDEX_INVALID)
2053 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2054 *next0 = TCP_OUTPUT_NEXT_DROP;
2055 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2060 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2061 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2062 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2063 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2066 *next0 = TCP_OUTPUT_NEXT_DROP;
2067 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2069 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2073 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2074 u32 * to_next, u32 n_bufs)
2076 tcp_connection_t *tc;
2082 for (i = 0; i < n_bufs; i++)
2084 b = vlib_get_buffer (vm, to_next[i]);
2085 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2087 th = vlib_buffer_get_current (b);
2088 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2090 t = vlib_add_trace (vm, node, b, sizeof (*t));
2091 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2092 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2097 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2098 tcp_connection_t * tc0, u8 is_ip4)
2100 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2101 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2102 b0->current_length);
2105 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2106 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2108 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2109 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
2113 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2115 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2118 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2120 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2121 data_len += b->total_length_not_including_first_buffer;
2123 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2127 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2128 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2129 b->flags |= VNET_BUFFER_F_GSO;
2130 vnet_buffer2 (b)->gso_l4_hdr_sz =
2131 sizeof (tcp_header_t) + tc->snd_opts_len;
2132 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2137 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2138 vlib_node_runtime_t * error_node, u16 * next0,
2141 /* If next_index is not drop use it */
2142 if (tc0->next_node_index)
2144 *next0 = tc0->next_node_index;
2145 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2149 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2152 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2153 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2159 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2160 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2162 if (PREDICT_FALSE (error0))
2164 b0->error = error_node->errors[error0];
2173 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2174 vlib_frame_t * frame, int is_ip4)
2176 u32 n_left_from, *from, thread_index = vm->thread_index;
2177 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2178 u16 nexts[VLIB_FRAME_SIZE], *next;
2180 from = vlib_frame_vector_args (frame);
2181 n_left_from = frame->n_vectors;
2182 tcp_set_time_now (tcp_get_worker (thread_index));
2184 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2185 tcp46_output_trace_frame (vm, node, from, n_left_from);
2187 vlib_get_buffers (vm, from, bufs, n_left_from);
2191 while (n_left_from >= 4)
2193 tcp_connection_t *tc0, *tc1;
2196 vlib_prefetch_buffer_header (b[2], STORE);
2197 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2199 vlib_prefetch_buffer_header (b[3], STORE);
2200 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2203 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2205 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2208 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2210 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2211 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2213 tcp_check_if_gso (tc0, b[0]);
2214 tcp_check_if_gso (tc1, b[1]);
2216 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2217 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2223 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2224 tcp_check_if_gso (tc0, b[0]);
2225 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2229 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2230 next[0] = TCP_OUTPUT_NEXT_DROP;
2234 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2235 tcp_check_if_gso (tc1, b[1]);
2236 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2240 b[1]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2241 next[1] = TCP_OUTPUT_NEXT_DROP;
2249 while (n_left_from > 0)
2251 tcp_connection_t *tc0;
2253 if (n_left_from > 1)
2255 vlib_prefetch_buffer_header (b[1], STORE);
2256 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2259 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2262 if (PREDICT_TRUE (tc0 != 0))
2264 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2265 tcp_check_if_gso (tc0, b[0]);
2266 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2270 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2271 next[0] = TCP_OUTPUT_NEXT_DROP;
2279 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2280 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2281 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2282 return frame->n_vectors;
2285 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2286 vlib_frame_t * from_frame)
2288 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2291 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2292 vlib_frame_t * from_frame)
2294 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2298 VLIB_REGISTER_NODE (tcp4_output_node) =
2300 .name = "tcp4-output",
2301 /* Takes a vector of packets. */
2302 .vector_size = sizeof (u32),
2303 .n_errors = TCP_N_ERROR,
2304 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2305 .error_strings = tcp_error_strings,
2306 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2308 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2309 foreach_tcp4_output_next
2312 .format_buffer = format_tcp_header,
2313 .format_trace = format_tcp_tx_trace,
2318 VLIB_REGISTER_NODE (tcp6_output_node) =
2320 .name = "tcp6-output",
2321 /* Takes a vector of packets. */
2322 .vector_size = sizeof (u32),
2323 .n_errors = TCP_N_ERROR,
2324 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2325 .error_strings = tcp_error_strings,
2326 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2328 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2329 foreach_tcp6_output_next
2332 .format_buffer = format_tcp_header,
2333 .format_trace = format_tcp_tx_trace,
2337 typedef enum _tcp_reset_next
2339 TCP_RESET_NEXT_DROP,
2340 TCP_RESET_NEXT_IP_LOOKUP,
2344 #define foreach_tcp4_reset_next \
2345 _(DROP, "error-drop") \
2346 _(IP_LOOKUP, "ip4-lookup")
2348 #define foreach_tcp6_reset_next \
2349 _(DROP, "error-drop") \
2350 _(IP_LOOKUP, "ip6-lookup")
2353 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2354 vlib_frame_t * from_frame, u8 is_ip4)
2356 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2357 u32 n_left_from, next_index, *from, *to_next;
2359 from = vlib_frame_vector_args (from_frame);
2360 n_left_from = from_frame->n_vectors;
2362 next_index = node->cached_next_index;
2364 while (n_left_from > 0)
2368 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2370 while (n_left_from > 0 && n_left_to_next > 0)
2382 n_left_to_next -= 1;
2384 b0 = vlib_get_buffer (vm, bi0);
2385 tcp_make_reset_in_place (vm, b0, is_ip4);
2387 /* Prepare to send to IP lookup */
2388 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2390 b0->error = node->errors[error0];
2391 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2392 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2394 th0 = vlib_buffer_get_current (b0);
2396 th0 = ip4_next_header ((ip4_header_t *) th0);
2398 th0 = ip6_next_header ((ip6_header_t *) th0);
2399 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2400 clib_memcpy_fast (&t0->tcp_header, th0,
2401 sizeof (t0->tcp_header));
2404 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2405 n_left_to_next, bi0, next0);
2407 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2409 return from_frame->n_vectors;
2412 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2413 vlib_frame_t * from_frame)
2415 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2418 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2419 vlib_frame_t * from_frame)
2421 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2425 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2426 .name = "tcp4-reset",
2427 .vector_size = sizeof (u32),
2428 .n_errors = TCP_N_ERROR,
2429 .error_strings = tcp_error_strings,
2430 .n_next_nodes = TCP_RESET_N_NEXT,
2432 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2433 foreach_tcp4_reset_next
2436 .format_trace = format_tcp_tx_trace,
2441 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2442 .name = "tcp6-reset",
2443 .vector_size = sizeof (u32),
2444 .n_errors = TCP_N_ERROR,
2445 .error_strings = tcp_error_strings,
2446 .n_next_nodes = TCP_RESET_N_NEXT,
2448 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2449 foreach_tcp6_reset_next
2452 .format_trace = format_tcp_tx_trace,
2457 * fd.io coding-style-patch-verification: ON
2460 * eval: (c-set-style "gnu")