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 vlib_error_desc_t tcp_output_error_counters[] = {
44 #define tcp_error(f, n, s, d) { #n, d, VL_COUNTER_SEVERITY_##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_tstamp (tc->c_thread_index);
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_tstamp (tc->c_thread_index);
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);
327 if (tc->flags & TCP_CONN_PSH_PENDING)
329 u32 max_deq = transport_max_tx_dequeue (&tc->connection);
330 /* Last byte marked for push */
331 tc->psh_seq = tc->snd_una + max_deq - 1;
336 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
338 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
339 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
340 b->total_length_not_including_first_buffer = 0;
342 vnet_buffer (b)->tcp.flags = 0;
343 /* Leave enough space for headers */
344 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
347 /* Compute TCP checksum in software when offloading is disabled for a connection */
349 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
350 ip46_address_t * src, ip46_address_t * dst)
353 u16 payload_length_host_byte_order;
356 /* Initialize checksum with ip header. */
357 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
358 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
359 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
361 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
363 sum0 = ip_csum_with_carry
364 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
365 sum0 = ip_csum_with_carry
366 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
369 return ip_calculate_l4_checksum (vm, p0, sum0,
370 payload_length_host_byte_order, NULL, 0,
375 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
376 ip46_address_t * src, ip46_address_t * dst)
379 u32 payload_length_host_byte_order;
381 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
383 clib_host_to_net_u32 (payload_length_host_byte_order +
384 (IP_PROTOCOL_TCP << 16));
386 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
387 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
389 return ip_calculate_l4_checksum (vm, p0, sum0,
390 payload_length_host_byte_order, NULL, 0,
395 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
398 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
400 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
401 vlib_main_t *vm = wrk->vm;
404 checksum = ip4_tcp_compute_checksum_custom
405 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
407 checksum = ip6_tcp_compute_checksum_custom
408 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
412 vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TCP_CKSUM);
421 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
424 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
425 u8 tcp_opts_len, tcp_hdr_opts_len;
429 wnd = tcp_window_to_advertise (tc, state);
431 /* Make and write options */
432 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
433 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
435 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
436 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
438 tcp_options_write ((u8 *) (th + 1), snd_opts);
440 th->checksum = tcp_compute_checksum (tc, b);
442 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
446 transport_rx_fifo_req_deq_ntf (&tc->connection);
447 tcp_zero_rwnd_sent_on (tc);
450 tcp_zero_rwnd_sent_off (tc);
454 * Convert buffer to ACK
457 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
459 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
460 TCP_EVT (TCP_EVT_ACK_SENT, tc);
461 tc->rcv_las = tc->rcv_nxt;
465 * Convert buffer to FIN-ACK
468 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
470 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
474 * Convert buffer to SYN
477 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
479 u8 tcp_hdr_opts_len, tcp_opts_len;
482 tcp_options_t snd_opts;
484 initial_wnd = tcp_initial_window_to_advertise (tc);
486 /* Make and write options */
487 clib_memset (&snd_opts, 0, sizeof (snd_opts));
488 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
489 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
491 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
492 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
494 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
495 tcp_options_write ((u8 *) (th + 1), &snd_opts);
496 th->checksum = tcp_compute_checksum (tc, b);
500 * Convert buffer to SYN-ACK
503 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
505 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
506 u8 tcp_opts_len, tcp_hdr_opts_len;
510 clib_memset (snd_opts, 0, sizeof (*snd_opts));
511 initial_wnd = tcp_initial_window_to_advertise (tc);
512 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
513 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
515 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
516 tc->rcv_nxt, tcp_hdr_opts_len,
517 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
518 tcp_options_write ((u8 *) (th + 1), snd_opts);
520 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
521 th->checksum = tcp_compute_checksum (tc, b);
525 tcp_enqueue_half_open (tcp_worker_ctx_t *wrk, tcp_connection_t *tc,
526 vlib_buffer_t *b, u32 bi)
528 vlib_main_t *vm = wrk->vm;
530 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
533 session_add_pending_tx_buffer (vm->thread_index, bi,
534 wrk->tco_next_node[!tc->c_is_ip4]);
536 if (vm->thread_index == 0 && vlib_num_workers ())
537 session_queue_run_on_main_thread (vm);
541 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
544 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
547 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
548 wrk->tco_next_node[!is_ip4]);
552 tcp_buffer_make_reset (vlib_main_t *vm, vlib_buffer_t *b, u8 is_ip4)
554 ip4_address_t src_ip4 = {}, dst_ip4 = {};
555 ip6_address_t src_ip6, dst_ip6;
556 u16 src_port, dst_port;
557 u32 tmp, len, seq, ack;
564 * Find IP and TCP headers and glean information from them. Assumes
565 * buffer was parsed by something like @ref tcp_input_lookup_buffer
567 th = tcp_buffer_hdr (b);
571 ih4 = vlib_buffer_get_current (b);
572 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
573 src_ip4.as_u32 = ih4->src_address.as_u32;
574 dst_ip4.as_u32 = ih4->dst_address.as_u32;
578 ih6 = vlib_buffer_get_current (b);
579 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
580 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
581 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
584 src_port = th->src_port;
585 dst_port = th->dst_port;
586 flags = TCP_FLAG_RST;
589 * RFC 793. If the ACK bit is off, sequence number zero is used,
590 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
591 * If the ACK bit is on,
592 * <SEQ=SEG.ACK><CTL=RST>
596 seq = th->ack_number;
601 flags |= TCP_FLAG_ACK;
602 tmp = clib_net_to_host_u32 (th->seq_number);
603 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
604 ack = clib_host_to_net_u32 (tmp + len);
609 * Clear and reuse current buffer for reset
611 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
612 vlib_buffer_free_one (vm, b->next_buffer);
614 /* Zero all flags but free list index and trace flag */
615 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
617 b->current_length = 0;
618 b->total_length_not_including_first_buffer = 0;
619 vnet_buffer (b)->tcp.flags = 0;
620 vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
623 * Add TCP and IP headers
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);
646 * Send reset without reusing existing buffer
648 * It extracts connection info out of original packet
651 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
652 u32 thread_index, u8 is_ip4)
654 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
655 vlib_main_t *vm = wrk->vm;
657 u8 tcp_hdr_len, flags = 0;
658 tcp_header_t *th, *pkt_th;
660 ip4_header_t *ih4, *pkt_ih4;
661 ip6_header_t *ih6, *pkt_ih6;
663 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
665 tcp_worker_stats_inc (wrk, no_buffer, 1);
669 b = vlib_get_buffer (vm, bi);
670 tcp_init_buffer (vm, b);
672 /* Make and write options */
673 tcp_hdr_len = sizeof (tcp_header_t);
677 pkt_ih4 = vlib_buffer_get_current (pkt);
678 pkt_th = ip4_next_header (pkt_ih4);
682 pkt_ih6 = vlib_buffer_get_current (pkt);
683 pkt_th = ip6_next_header (pkt_ih6);
686 if (tcp_ack (pkt_th))
688 flags = TCP_FLAG_RST;
689 seq = pkt_th->ack_number;
690 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
694 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
696 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
699 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
700 seq, ack, tcp_hdr_len, flags, 0);
702 /* Swap src and dst ip */
705 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
706 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
707 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
708 tcp_csum_offload (tc));
709 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
714 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
716 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
717 &pkt_ih6->src_address,
719 tc->ipv6_flow_label);
720 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
724 tcp_enqueue_half_open (wrk, tc, b, bi);
725 TCP_EVT (TCP_EVT_RST_SENT, tc);
726 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
727 TCP_ERROR_RST_SENT, 1);
731 * Build and set reset packet for connection
734 tcp_send_reset (tcp_connection_t * tc)
736 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
737 vlib_main_t *vm = wrk->vm;
741 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
744 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
746 tcp_worker_stats_inc (wrk, no_buffer, 1);
749 b = vlib_get_buffer (vm, bi);
750 tcp_init_buffer (vm, b);
752 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
753 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
754 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
755 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
756 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
757 tc->rcv_nxt, tcp_hdr_opts_len, flags,
759 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
760 th->checksum = tcp_compute_checksum (tc, b);
761 ASSERT (opts_write_len == tc->snd_opts_len);
762 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
763 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
764 TCP_EVT (TCP_EVT_RST_SENT, tc);
765 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
766 TCP_ERROR_RST_SENT, 1);
772 * Builds a SYN packet for a half-open connection and sends it to tcp-output.
773 * The packet is handled by main thread and because half-open and established
774 * connections use the same pool the connection can be retrieved without
778 tcp_send_syn (tcp_connection_t * tc)
780 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
781 vlib_main_t *vm = wrk->vm;
786 * Setup retransmit and establish timers before requesting buffer
787 * such that we can return if we've ran out.
789 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
790 tc->rto * TCP_TO_TIMER_TICK);
792 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
794 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
795 tcp_cfg.alloc_err_timeout);
796 tcp_worker_stats_inc (wrk, no_buffer, 1);
800 b = vlib_get_buffer (vm, bi);
801 tcp_init_buffer (vm, b);
802 tcp_make_syn (tc, b);
804 /* Measure RTT with this */
805 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
806 tc->rtt_seq = tc->snd_nxt;
809 tcp_enqueue_half_open (wrk, tc, b, bi);
810 TCP_EVT (TCP_EVT_SYN_SENT, tc);
814 tcp_send_synack (tcp_connection_t * tc)
816 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
817 vlib_main_t *vm = wrk->vm;
821 ASSERT (tc->snd_una != tc->snd_nxt);
822 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
824 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
826 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
827 tcp_cfg.alloc_err_timeout);
828 tcp_worker_stats_inc (wrk, no_buffer, 1);
832 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
833 b = vlib_get_buffer (vm, bi);
834 tcp_init_buffer (vm, b);
835 tcp_make_synack (tc, b);
836 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
837 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
844 tcp_send_fin (tcp_connection_t * tc)
846 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
847 vlib_main_t *vm = wrk->vm;
852 fin_snt = tc->flags & TCP_CONN_FINSNT;
856 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
858 /* Out of buffers so program fin retransmit ASAP */
859 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
860 tcp_cfg.alloc_err_timeout);
864 /* Make sure retransmit retries a fin not data */
865 tc->flags |= TCP_CONN_FINSNT;
866 tcp_worker_stats_inc (wrk, no_buffer, 1);
870 /* If we have non-dupacks programmed, no need to send them */
871 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
872 tc->flags &= ~TCP_CONN_SNDACK;
874 b = vlib_get_buffer (vm, bi);
875 tcp_init_buffer (vm, b);
876 tcp_make_fin (tc, b);
877 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
878 TCP_EVT (TCP_EVT_FIN_SENT, tc);
879 /* Account for the FIN */
881 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
884 tc->flags |= TCP_CONN_FINSNT;
885 tc->flags &= ~TCP_CONN_FINPNDG;
890 * Push TCP header and update connection variables. Should only be called
891 * for segments with data, not for 'control' packets.
894 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
895 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
897 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
898 u32 advertise_wnd, data_len;
899 tcp_main_t *tm = &tcp_main;
902 data_len = b->current_length;
903 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
904 data_len += b->total_length_not_including_first_buffer;
906 vnet_buffer (b)->tcp.flags = 0;
907 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
910 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
912 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
915 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
917 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
919 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
921 if (seq_geq (tc->psh_seq, snd_nxt)
922 && seq_lt (tc->psh_seq, snd_nxt + data_len))
923 flags |= TCP_FLAG_PSH;
925 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
926 tc->rcv_nxt, tcp_hdr_opts_len, flags,
931 clib_memcpy_fast ((u8 *) (th + 1),
932 tm->wrk_ctx[tc->c_thread_index].cached_opts,
937 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
938 ASSERT (len == tc->snd_opts_len);
942 * Update connection variables
946 tc->snd_nxt += data_len;
947 tc->rcv_las = tc->rcv_nxt;
949 tc->bytes_out += data_len;
950 tc->data_segs_out += 1;
952 th->checksum = tcp_compute_checksum (tc, b);
954 TCP_EVT (TCP_EVT_PKTIZE, tc);
958 tcp_buffer_len (vlib_buffer_t * b)
960 u32 data_len = b->current_length;
961 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
962 data_len += b->total_length_not_including_first_buffer;
967 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
969 tcp_connection_t *tc = (tcp_connection_t *) tconn;
971 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
972 tcp_bt_track_tx (tc, tcp_buffer_len (b));
974 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
975 /* update_snd_nxt */ 1);
977 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
978 /* If not tracking an ACK, start tracking */
979 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
981 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
982 tc->rtt_seq = tc->snd_nxt;
984 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
986 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
987 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
994 tcp_send_ack (tcp_connection_t * tc)
996 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
997 vlib_main_t *vm = wrk->vm;
1001 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1003 tcp_update_rcv_wnd (tc);
1004 tcp_worker_stats_inc (wrk, no_buffer, 1);
1007 b = vlib_get_buffer (vm, bi);
1008 tcp_init_buffer (vm, b);
1009 tcp_make_ack (tc, b);
1010 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1014 tcp_program_ack (tcp_connection_t * tc)
1016 if (!(tc->flags & TCP_CONN_SNDACK))
1018 session_add_self_custom_tx_evt (&tc->connection, 1);
1019 tc->flags |= TCP_CONN_SNDACK;
1024 tcp_program_dupack (tcp_connection_t * tc)
1026 if (!(tc->flags & TCP_CONN_SNDACK))
1028 session_add_self_custom_tx_evt (&tc->connection, 1);
1029 tc->flags |= TCP_CONN_SNDACK;
1031 if (tc->pending_dupacks < 255)
1032 tc->pending_dupacks += 1;
1036 tcp_program_retransmit (tcp_connection_t * tc)
1038 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1040 session_add_self_custom_tx_evt (&tc->connection, 0);
1041 tc->flags |= TCP_CONN_RXT_PENDING;
1046 * Send window update ack
1048 * Ensures that it will be sent only once, after a zero rwnd has been
1049 * advertised in a previous ack, and only if rwnd has grown beyond a
1050 * configurable value.
1053 tcp_send_window_update_ack (tcp_connection_t * tc)
1055 if (tcp_zero_rwnd_sent (tc))
1057 tcp_update_rcv_wnd (tc);
1058 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1060 tcp_zero_rwnd_sent_off (tc);
1061 tcp_program_ack (tc);
1067 * Allocate a new buffer and build a new tcp segment
1069 * @param wrk tcp worker
1070 * @param tc connection for which the segment will be allocated
1071 * @param offset offset of the first byte in the tx fifo
1072 * @param max_deq_byte segment size
1073 * @param[out] b pointer to buffer allocated
1075 * @return the number of bytes in the segment or 0 if buffer cannot be
1076 * allocated or no data available
1079 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1080 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1082 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1083 vlib_main_t *vm = wrk->vm;
1088 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1093 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1096 * Allocate and fill in buffer(s)
1099 /* Easy case, buffer size greater than mss */
1100 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1102 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1104 tcp_worker_stats_inc (wrk, no_buffer, 1);
1107 *b = vlib_get_buffer (vm, bi);
1108 data = tcp_init_buffer (vm, *b);
1109 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1111 ASSERT (n_bytes == max_deq_bytes);
1112 b[0]->current_length = n_bytes;
1113 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1114 /* burst */ 0, /* update_snd_nxt */ 0);
1116 /* Split mss into multiple buffers */
1119 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1120 u16 n_peeked, len_to_deq;
1121 vlib_buffer_t *chain_b, *prev_b;
1124 /* Make sure we have enough buffers */
1125 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1126 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1127 CLIB_CACHE_LINE_BYTES);
1128 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1129 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1132 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1133 tcp_worker_stats_inc (wrk, no_buffer, 1);
1137 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1138 data = tcp_init_buffer (vm, *b);
1139 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1141 TRANSPORT_MAX_HDRS_LEN);
1142 b[0]->current_length = n_bytes;
1143 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1144 b[0]->total_length_not_including_first_buffer = 0;
1145 max_deq_bytes -= n_bytes;
1148 for (i = 1; i < n_bufs_per_seg; i++)
1151 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1152 chain_bi = wrk->tx_buffers[--n_bufs];
1153 chain_b = vlib_get_buffer (vm, chain_bi);
1154 chain_b->current_data = 0;
1155 data = vlib_buffer_get_current (chain_b);
1156 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1159 ASSERT (n_peeked == len_to_deq);
1160 n_bytes += n_peeked;
1161 chain_b->current_length = n_peeked;
1162 chain_b->next_buffer = 0;
1164 /* update previous buffer */
1165 prev_b->next_buffer = chain_bi;
1166 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1168 max_deq_bytes -= n_peeked;
1169 b[0]->total_length_not_including_first_buffer += n_peeked;
1172 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1173 /* burst */ 0, /* update_snd_nxt */ 0);
1175 if (PREDICT_FALSE (n_bufs))
1177 clib_warning ("not all buffers consumed");
1178 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1182 ASSERT (n_bytes > 0);
1183 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1189 * Build a retransmit segment
1191 * @return the number of bytes in the segment or 0 if there's nothing to
1195 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1196 tcp_connection_t * tc, u32 offset,
1197 u32 max_deq_bytes, vlib_buffer_t ** b)
1199 u32 start, available_bytes;
1202 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1203 ASSERT (max_deq_bytes != 0);
1206 * Make sure we can retransmit something
1208 available_bytes = transport_max_tx_dequeue (&tc->connection);
1209 ASSERT (available_bytes >= offset);
1210 available_bytes -= offset;
1211 if (!available_bytes)
1214 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1215 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1217 start = tc->snd_una + offset;
1218 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1220 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1224 tc->snd_rxt_bytes += n_bytes;
1226 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1227 tcp_bt_track_rxt (tc, start, start + n_bytes);
1229 tc->bytes_retrans += n_bytes;
1230 tc->segs_retrans += 1;
1231 tcp_worker_stats_inc (wrk, rxt_segs, 1);
1232 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1238 tcp_check_sack_reneging (tcp_connection_t * tc)
1240 sack_scoreboard_t *sb = &tc->sack_sb;
1241 sack_scoreboard_hole_t *hole;
1243 hole = scoreboard_first_hole (sb);
1244 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1247 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1251 * Reset congestion control, switch cwnd to loss window and try again.
1254 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1256 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1258 tc->prev_ssthresh = tc->ssthresh;
1259 tc->prev_cwnd = tc->cwnd;
1261 /* If we entrered loss without fast recovery, notify cc algo of the
1262 * congestion event such that it can update ssthresh and its state */
1263 if (!tcp_in_fastrecovery (tc))
1264 tcp_cc_congestion (tc);
1266 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1270 tc->cwnd_acc_bytes = 0;
1271 tc->tr_occurences += 1;
1272 tc->sack_sb.reorder = TCP_DUPACK_THRESHOLD;
1273 tcp_recovery_on (tc);
1277 tcp_timer_retransmit_handler (tcp_connection_t * tc)
1279 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1280 vlib_main_t *vm = wrk->vm;
1281 vlib_buffer_t *b = 0;
1284 tcp_worker_stats_inc (wrk, tr_events, 1);
1286 /* Should be handled by a different handler */
1287 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
1290 /* Wait-close and retransmit could pop at the same time */
1291 if (tc->state == TCP_STATE_CLOSED)
1294 if (tc->state >= TCP_STATE_ESTABLISHED)
1296 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1298 /* Lost FIN, retransmit and return */
1299 if (tc->flags & TCP_CONN_FINSNT)
1303 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1307 /* Shouldn't be here */
1308 if (tc->snd_una == tc->snd_nxt)
1310 ASSERT (!tcp_in_recovery (tc));
1315 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1316 * to persist timer timeout */
1317 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1320 tcp_update_rto (tc);
1323 /* Peer is dead or network connectivity is lost. Close connection.
1324 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1325 * a min rto of 0.2s we need to retry about 8 times. */
1326 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1328 tcp_send_reset (tc);
1329 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1330 session_transport_closing_notify (&tc->connection);
1331 session_transport_closed_notify (&tc->connection);
1332 tcp_connection_timers_reset (tc);
1333 tcp_program_cleanup (wrk, tc);
1334 tcp_worker_stats_inc (wrk, tr_abort, 1);
1338 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1339 tcp_check_sack_reneging (tc);
1341 /* Update send congestion to make sure that rxt has data to send */
1342 tc->snd_congestion = tc->snd_nxt;
1344 /* Send the first unacked segment. If we're short on buffers, return
1345 * as soon as possible */
1346 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1347 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1350 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
1351 tcp_cfg.alloc_err_timeout);
1355 bi = vlib_get_buffer_index (vm, b);
1356 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1358 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1359 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1362 if (tc->rto_boff == 1)
1364 tcp_cc_init_rxt_timeout (tc);
1365 /* Record timestamp. Eifel detection algorithm RFC3522 */
1366 tc->snd_rxt_ts = tcp_tstamp (tc);
1369 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1370 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1372 tcp_program_retransmit (tc);
1374 /* Retransmit SYN-ACK */
1375 else if (tc->state == TCP_STATE_SYN_RCVD)
1377 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1381 /* Passive open establish timeout */
1382 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1384 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1385 tcp_connection_timers_reset (tc);
1386 tcp_program_cleanup (wrk, tc);
1387 tcp_worker_stats_inc (wrk, tr_abort, 1);
1391 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1393 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
1394 tcp_cfg.alloc_err_timeout);
1395 tcp_worker_stats_inc (wrk, no_buffer, 1);
1400 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1401 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1403 ASSERT (tc->snd_una != tc->snd_nxt);
1404 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1406 b = vlib_get_buffer (vm, bi);
1407 tcp_init_buffer (vm, b);
1408 tcp_make_synack (tc, b);
1409 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1411 /* Retransmit timer already updated, just enqueue to output */
1412 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1416 ASSERT (tc->state == TCP_STATE_CLOSED);
1422 * SYN retransmit timer handler. Active open only.
1425 tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
1427 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1428 vlib_main_t *vm = wrk->vm;
1429 vlib_buffer_t *b = 0;
1432 /* Note: the connection may have transitioned to ESTABLISHED... */
1433 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
1436 /* Half-open connection actually moved to established but we were
1437 * waiting for syn retransmit to pop to call cleanup from the right
1439 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1441 if (tcp_half_open_connection_cleanup (tc))
1442 TCP_DBG ("could not remove half-open connection");
1446 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1449 /* Active open establish timeout */
1450 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1452 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
1453 tcp_connection_cleanup (tc);
1457 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1459 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1460 tcp_cfg.alloc_err_timeout);
1461 tcp_worker_stats_inc (wrk, no_buffer, 1);
1465 /* Try without increasing RTO a number of times. If this fails,
1466 * start growing RTO exponentially */
1468 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1469 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1471 b = vlib_get_buffer (vm, bi);
1472 tcp_init_buffer (vm, b);
1473 tcp_make_syn (tc, b);
1475 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1477 tcp_enqueue_half_open (wrk, tc, b, bi);
1479 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1480 tc->rto * TCP_TO_TIMER_TICK);
1484 * Got 0 snd_wnd from peer, try to do something about it.
1488 tcp_timer_persist_handler (tcp_connection_t * tc)
1490 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1491 u32 bi, max_snd_bytes, available_bytes, offset;
1492 tcp_main_t *tm = vnet_get_tcp_main ();
1493 vlib_main_t *vm = wrk->vm;
1498 /* Problem already solved or worse */
1499 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1500 || (tc->flags & TCP_CONN_FINSNT))
1501 goto update_scheduler;
1503 available_bytes = transport_max_tx_dequeue (&tc->connection);
1504 offset = tc->snd_nxt - tc->snd_una;
1506 /* Reprogram persist if no new bytes available to send. We may have data
1508 if (!available_bytes)
1510 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1514 if (available_bytes <= offset)
1515 goto update_scheduler;
1517 /* Increment RTO backoff */
1519 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1522 * Try to force the first unsent segment (or buffer)
1524 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1526 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1527 tcp_worker_stats_inc (wrk, no_buffer, 1);
1531 b = vlib_get_buffer (vm, bi);
1532 data = tcp_init_buffer (vm, b);
1534 tcp_validate_txf_size (tc, offset);
1535 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1536 max_snd_bytes = clib_min (tc->snd_mss,
1537 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1538 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1540 b->current_length = n_bytes;
1541 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1542 || tc->snd_una == tc->snd_nxt
1543 || tc->rto_boff > 1));
1545 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1547 tcp_bt_check_app_limited (tc);
1548 tcp_bt_track_tx (tc, n_bytes);
1551 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1552 /* burst */ 0, /* update_snd_nxt */ 1);
1553 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
1554 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1556 /* Just sent new data, enable retransmit */
1557 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1563 if (tcp_is_descheduled (tc))
1564 transport_connection_reschedule (&tc->connection);
1568 * Retransmit first unacked segment
1571 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1573 vlib_main_t *vm = wrk->vm;
1577 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1579 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1583 bi = vlib_get_buffer_index (vm, b);
1584 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1590 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1593 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1594 vlib_main_t *vm = wrk->vm;
1595 vlib_buffer_t *b = 0;
1597 offset = tc->snd_nxt - tc->snd_una;
1598 available_wnd = tc->snd_wnd - offset;
1599 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1601 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1602 tcp_bt_check_app_limited (tc);
1604 while (n_segs < burst_size)
1606 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1610 bi = vlib_get_buffer_index (vm, b);
1611 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1612 offset += n_written;
1615 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1616 tcp_bt_track_tx (tc, n_written);
1618 tc->snd_nxt += n_written;
1626 * Estimate send space using proportional rate reduction (RFC6937)
1629 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1634 pipe = tcp_flight_size (tc);
1635 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1637 if (pipe > tc->ssthresh)
1639 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1645 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1646 space = clib_min (tc->ssthresh - pipe, limit);
1648 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1653 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1654 sack_scoreboard_t * sb)
1656 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1657 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1659 if (tcp_fastrecovery_first (tc))
1662 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1666 tcp_max_tx_deq (tcp_connection_t * tc)
1668 return (transport_max_tx_dequeue (&tc->connection)
1669 - (tc->snd_nxt - tc->snd_una));
1672 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1673 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1674 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1677 * Do retransmit with SACKs
1680 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1683 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1684 u8 snd_limited = 0, can_rescue = 0;
1685 u32 bi, max_deq, burst_bytes;
1686 sack_scoreboard_hole_t *hole;
1687 vlib_main_t *vm = wrk->vm;
1688 vlib_buffer_t *b = 0;
1689 sack_scoreboard_t *sb;
1692 ASSERT (tcp_in_cong_recovery (tc));
1694 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1695 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1698 tcp_program_retransmit (tc);
1702 if (tcp_in_recovery (tc))
1703 snd_space = tcp_available_cc_snd_space (tc);
1705 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1707 if (snd_space < tc->snd_mss)
1712 /* Check if snd_una is a lost retransmit */
1713 if (pool_elts (sb->holes)
1714 && seq_gt (sb->high_sacked, tc->snd_congestion)
1715 && tc->rxt_head != tc->snd_una
1716 && tcp_retransmit_should_retry_head (tc, sb))
1718 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1719 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1722 tcp_program_retransmit (tc);
1725 bi = vlib_get_buffer_index (vm, b);
1726 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1729 tc->rxt_head = tc->snd_una;
1730 tc->rxt_delivered += n_written;
1731 tc->prr_delivered += n_written;
1732 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1735 tcp_fastrecovery_first_off (tc);
1737 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1738 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1740 max_deq = transport_max_tx_dequeue (&tc->connection);
1741 max_deq -= tc->snd_nxt - tc->snd_una;
1743 while (snd_space > 0 && n_segs < burst_size)
1745 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1749 /* We are out of lost holes to retransmit so send some new data. */
1750 if (max_deq > tc->snd_mss)
1755 /* Make sure we don't exceed available window and leave space
1756 * for one more packet, to avoid zero window acks */
1757 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1758 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1759 snd_space = clib_min (snd_space, av_wnd);
1760 snd_space = clib_min (max_deq, snd_space);
1761 burst_size = clib_min (burst_size - n_segs,
1762 snd_space / tc->snd_mss);
1763 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1764 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1765 if (max_deq > n_segs_new * tc->snd_mss)
1766 tcp_program_retransmit (tc);
1768 n_segs += n_segs_new;
1772 if (tcp_in_recovery (tc) || !can_rescue
1773 || scoreboard_rescue_rxt_valid (sb, tc))
1776 /* If rescue rxt undefined or less than snd_una then one segment of
1777 * up to SMSS octets that MUST include the highest outstanding
1778 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1779 * RecoveryPoint. HighRxt MUST NOT be updated.
1781 hole = scoreboard_last_hole (sb);
1782 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1783 max_bytes = clib_min (max_bytes, snd_space);
1784 offset = hole->end - tc->snd_una - max_bytes;
1785 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1790 sb->rescue_rxt = tc->snd_congestion;
1791 bi = vlib_get_buffer_index (vm, b);
1792 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1797 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1798 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1802 offset = sb->high_rxt - tc->snd_una;
1803 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1805 ASSERT (n_written <= snd_space);
1807 /* Nothing left to retransmit */
1811 bi = vlib_get_buffer_index (vm, b);
1812 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1814 sb->high_rxt += n_written;
1815 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1817 snd_space -= n_written;
1822 tcp_program_retransmit (tc);
1826 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
1831 * Fast retransmit without SACK info
1834 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1837 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
1838 u32 burst_bytes, sent_bytes;
1839 vlib_main_t *vm = wrk->vm;
1840 int snd_space, n_segs = 0;
1844 ASSERT (tcp_in_cong_recovery (tc));
1845 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1847 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1848 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1851 tcp_program_retransmit (tc);
1855 snd_space = tcp_available_cc_snd_space (tc);
1856 cc_limited = snd_space < burst_bytes;
1858 if (!tcp_fastrecovery_first (tc))
1861 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1863 while (snd_space > 0 && n_segs < burst_size)
1865 max_bytes = clib_min (tc->snd_mss,
1866 tc->snd_congestion - tc->snd_una - offset);
1869 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1872 /* Nothing left to retransmit */
1876 bi = vlib_get_buffer_index (vm, b);
1877 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1878 snd_space -= n_written;
1879 offset += n_written;
1883 if (n_segs == burst_size)
1888 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1889 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1892 max_deq = transport_max_tx_dequeue (&tc->connection);
1893 max_deq -= tc->snd_nxt - tc->snd_una;
1896 snd_space = clib_min (max_deq, snd_space);
1897 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1898 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1899 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
1900 tcp_program_retransmit (tc);
1901 n_segs += n_segs_now;
1905 tcp_fastrecovery_first_off (tc);
1907 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1908 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1909 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1915 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1919 if (!tc->pending_dupacks)
1921 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1922 || tc->state != TCP_STATE_ESTABLISHED)
1930 /* If we're supposed to send dupacks but have no ooo data
1931 * send only one ack */
1932 if (!vec_len (tc->snd_sacks))
1935 tc->dupacks_out += 1;
1936 tc->pending_dupacks = 0;
1940 /* Start with first sack block */
1941 tc->snd_sack_pos = 0;
1943 /* Generate enough dupacks to cover all sack blocks. Do not generate
1944 * more sacks than the number of packets received. But do generate at
1945 * least 3, i.e., the number needed to signal congestion, if needed. */
1946 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1947 n_acks = clib_min (n_acks, tc->pending_dupacks);
1948 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1949 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1952 if (n_acks < max_burst_size)
1954 tc->pending_dupacks = 0;
1955 tc->snd_sack_pos = 0;
1956 tc->dupacks_out += n_acks;
1961 TCP_DBG ("constrained by burst size");
1962 tc->pending_dupacks = n_acks - max_burst_size;
1963 tc->dupacks_out += max_burst_size;
1964 tcp_program_dupack (tc);
1965 return max_burst_size;
1970 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
1972 tcp_worker_ctx_t *wrk;
1975 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
1978 wrk = tcp_get_worker (tc->c_thread_index);
1980 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1981 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
1983 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
1989 tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
1991 tcp_connection_t *tc = (tcp_connection_t *) conn;
1994 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
1996 tc->flags &= ~TCP_CONN_RXT_PENDING;
1997 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
2000 if (!(tc->flags & TCP_CONN_SNDACK))
2003 tc->flags &= ~TCP_CONN_SNDACK;
2005 /* We have retransmitted packets and no dupack */
2006 if (n_segs && !tc->pending_dupacks)
2009 if (sp->max_burst_size <= n_segs)
2011 tcp_program_ack (tc);
2015 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
2019 #endif /* CLIB_MARCH_VARIANT */
2022 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2023 u16 * next0, u32 * error0)
2025 ip_adjacency_t *adj;
2028 /* Not thread safe but as long as the connection exists the adj should
2030 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2032 if (ai == ADJ_INDEX_INVALID)
2034 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2035 *next0 = TCP_OUTPUT_NEXT_DROP;
2036 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2041 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2042 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2043 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2044 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2047 *next0 = TCP_OUTPUT_NEXT_DROP;
2048 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2050 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2054 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2055 u32 * to_next, u32 n_bufs)
2057 tcp_connection_t *tc;
2063 for (i = 0; i < n_bufs; i++)
2065 b = vlib_get_buffer (vm, to_next[i]);
2066 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2068 th = vlib_buffer_get_current (b);
2069 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2071 t = vlib_add_trace (vm, node, b, sizeof (*t));
2072 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2073 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2078 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2079 tcp_connection_t * tc0, u8 is_ip4)
2081 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2082 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2083 b0->current_length);
2086 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2087 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2089 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2090 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
2094 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2096 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2099 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2101 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2102 data_len += b->total_length_not_including_first_buffer;
2104 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2108 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2109 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2110 b->flags |= VNET_BUFFER_F_GSO;
2111 vnet_buffer2 (b)->gso_l4_hdr_sz =
2112 sizeof (tcp_header_t) + tc->snd_opts_len;
2113 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2118 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2119 vlib_node_runtime_t * error_node, u16 * next0,
2122 /* If next_index is not drop use it */
2123 if (tc0->next_node_index)
2125 *next0 = tc0->next_node_index;
2126 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2130 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2133 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2134 vnet_buffer (b0)->sw_if_index[VLIB_RX] = tc0->sw_if_index;
2140 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2141 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2143 if (PREDICT_FALSE (error0))
2145 b0->error = error_node->errors[error0];
2154 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2155 vlib_frame_t * frame, int is_ip4)
2157 u32 n_left_from, *from, thread_index = vm->thread_index;
2158 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2159 u16 nexts[VLIB_FRAME_SIZE], *next;
2161 from = vlib_frame_vector_args (frame);
2162 n_left_from = frame->n_vectors;
2163 tcp_update_time_now (tcp_get_worker (thread_index));
2165 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2166 tcp46_output_trace_frame (vm, node, from, n_left_from);
2168 vlib_get_buffers (vm, from, bufs, n_left_from);
2172 while (n_left_from >= 4)
2174 tcp_connection_t *tc0, *tc1;
2177 vlib_prefetch_buffer_header (b[2], STORE);
2178 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2180 vlib_prefetch_buffer_header (b[3], STORE);
2181 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2184 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2186 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2189 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2191 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2192 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2194 tcp_check_if_gso (tc0, b[0]);
2195 tcp_check_if_gso (tc1, b[1]);
2197 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2198 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2204 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2205 tcp_check_if_gso (tc0, b[0]);
2206 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2210 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2211 next[0] = TCP_OUTPUT_NEXT_DROP;
2215 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2216 tcp_check_if_gso (tc1, b[1]);
2217 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2221 b[1]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2222 next[1] = TCP_OUTPUT_NEXT_DROP;
2230 while (n_left_from > 0)
2232 tcp_connection_t *tc0;
2234 if (n_left_from > 1)
2236 vlib_prefetch_buffer_header (b[1], STORE);
2237 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2240 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2243 if (PREDICT_TRUE (tc0 != 0))
2245 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2246 tcp_check_if_gso (tc0, b[0]);
2247 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2251 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2252 next[0] = TCP_OUTPUT_NEXT_DROP;
2260 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2261 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2262 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2263 return frame->n_vectors;
2266 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2267 vlib_frame_t * from_frame)
2269 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2272 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2273 vlib_frame_t * from_frame)
2275 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2279 VLIB_REGISTER_NODE (tcp4_output_node) =
2281 .name = "tcp4-output",
2282 /* Takes a vector of packets. */
2283 .vector_size = sizeof (u32),
2284 .n_errors = TCP_N_ERROR,
2285 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2286 .error_counters = tcp_output_error_counters,
2287 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2289 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2290 foreach_tcp4_output_next
2293 .format_buffer = format_tcp_header,
2294 .format_trace = format_tcp_tx_trace,
2299 VLIB_REGISTER_NODE (tcp6_output_node) =
2301 .name = "tcp6-output",
2302 /* Takes a vector of packets. */
2303 .vector_size = sizeof (u32),
2304 .n_errors = TCP_N_ERROR,
2305 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2306 .error_counters = tcp_output_error_counters,
2307 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2309 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2310 foreach_tcp6_output_next
2313 .format_buffer = format_tcp_header,
2314 .format_trace = format_tcp_tx_trace,
2318 typedef enum _tcp_reset_next
2320 TCP_RESET_NEXT_DROP,
2321 TCP_RESET_NEXT_IP_LOOKUP,
2325 #define foreach_tcp4_reset_next \
2326 _(DROP, "error-drop") \
2327 _(IP_LOOKUP, "ip4-lookup")
2329 #define foreach_tcp6_reset_next \
2330 _(DROP, "error-drop") \
2331 _(IP_LOOKUP, "ip6-lookup")
2334 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2335 vlib_frame_t * from_frame, u8 is_ip4)
2337 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2338 u32 n_left_from, next_index, *from, *to_next;
2340 from = vlib_frame_vector_args (from_frame);
2341 n_left_from = from_frame->n_vectors;
2343 next_index = node->cached_next_index;
2345 while (n_left_from > 0)
2349 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2351 while (n_left_from > 0 && n_left_to_next > 0)
2363 n_left_to_next -= 1;
2365 b0 = vlib_get_buffer (vm, bi0);
2366 tcp_buffer_make_reset (vm, b0, is_ip4);
2368 /* Prepare to send to IP lookup */
2369 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2371 b0->error = node->errors[error0];
2372 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2373 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2375 th0 = vlib_buffer_get_current (b0);
2377 th0 = ip4_next_header ((ip4_header_t *) th0);
2379 th0 = ip6_next_header ((ip6_header_t *) th0);
2380 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2381 clib_memcpy_fast (&t0->tcp_header, th0,
2382 sizeof (t0->tcp_header));
2385 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2386 n_left_to_next, bi0, next0);
2388 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2390 return from_frame->n_vectors;
2393 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2394 vlib_frame_t * from_frame)
2396 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2399 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2400 vlib_frame_t * from_frame)
2402 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2406 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2407 .name = "tcp4-reset",
2408 .vector_size = sizeof (u32),
2409 .n_errors = TCP_N_ERROR,
2410 .error_counters = tcp_output_error_counters,
2411 .n_next_nodes = TCP_RESET_N_NEXT,
2413 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2414 foreach_tcp4_reset_next
2417 .format_trace = format_tcp_tx_trace,
2422 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2423 .name = "tcp6-reset",
2424 .vector_size = sizeof (u32),
2425 .n_errors = TCP_N_ERROR,
2426 .error_counters = tcp_output_error_counters,
2427 .n_next_nodes = TCP_RESET_N_NEXT,
2429 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2430 foreach_tcp6_reset_next
2433 .format_trace = format_tcp_tx_trace,
2438 * fd.io coding-style-patch-verification: ON
2441 * eval: (c-set-style "gnu")