blob: 05db72770f53be4e29323bc82db1893fd8a0e88d [file] [log] [blame]
Dave Barach68b0fb02017-02-28 15:15:56 -05001/*
Florin Coras222e1f412019-02-16 20:47:32 -08002 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
Dave Barach68b0fb02017-02-28 15:15:56 -05003 * 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:
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
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.
14 */
15
16#include <vnet/tcp/tcp.h>
Florin Corasb2215d62017-08-01 16:56:58 -070017#include <math.h>
Dave Barach68b0fb02017-02-28 15:15:56 -050018
Dave Barach2c25a622017-06-26 11:35:07 -040019typedef enum _tcp_output_next
Dave Barach68b0fb02017-02-28 15:15:56 -050020{
21 TCP_OUTPUT_NEXT_DROP,
Dave Barach2c25a622017-06-26 11:35:07 -040022 TCP_OUTPUT_NEXT_IP_LOOKUP,
Florin Corasf9d05682018-04-26 08:26:52 -070023 TCP_OUTPUT_NEXT_IP_REWRITE,
24 TCP_OUTPUT_NEXT_IP_ARP,
Dave Barach68b0fb02017-02-28 15:15:56 -050025 TCP_OUTPUT_N_NEXT
26} tcp_output_next_t;
27
28#define foreach_tcp4_output_next \
29 _ (DROP, "error-drop") \
Florin Corasf9d05682018-04-26 08:26:52 -070030 _ (IP_LOOKUP, "ip4-lookup") \
31 _ (IP_REWRITE, "ip4-rewrite") \
32 _ (IP_ARP, "ip4-arp")
Dave Barach68b0fb02017-02-28 15:15:56 -050033
34#define foreach_tcp6_output_next \
35 _ (DROP, "error-drop") \
Florin Corasf9d05682018-04-26 08:26:52 -070036 _ (IP_LOOKUP, "ip6-lookup") \
37 _ (IP_REWRITE, "ip6-rewrite") \
38 _ (IP_ARP, "ip6-discover-neighbor")
Dave Barach68b0fb02017-02-28 15:15:56 -050039
40static char *tcp_error_strings[] = {
41#define tcp_error(n,s) s,
42#include <vnet/tcp/tcp_error.def>
43#undef tcp_error
44};
45
46typedef struct
47{
Clement Durand6cf260c2017-04-13 13:27:04 +020048 tcp_header_t tcp_header;
49 tcp_connection_t tcp_connection;
Dave Barach68b0fb02017-02-28 15:15:56 -050050} tcp_tx_trace_t;
51
Filip Tehlare275bed2019-03-06 00:06:56 -080052static u8 *
Dave Barach68b0fb02017-02-28 15:15:56 -050053format_tcp_tx_trace (u8 * s, va_list * args)
54{
55 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
56 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
Clement Durand6cf260c2017-04-13 13:27:04 +020057 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
Christophe Fontained3c008d2017-10-02 18:10:54 +020058 u32 indent = format_get_indent (s);
Dave Barach68b0fb02017-02-28 15:15:56 -050059
Clement Durand6cf260c2017-04-13 13:27:04 +020060 s = format (s, "%U\n%U%U",
61 format_tcp_header, &t->tcp_header, 128,
62 format_white_space, indent,
Florin Corasbb292f42017-05-19 09:49:19 -070063 format_tcp_connection, &t->tcp_connection, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -050064
65 return s;
66}
67
Filip Tehlare275bed2019-03-06 00:06:56 -080068#ifndef CLIB_MARCH_VARIANT
Dave Barach68b0fb02017-02-28 15:15:56 -050069static u8
Florin Coras4eeeaaf2017-09-05 14:03:37 -040070tcp_window_compute_scale (u32 window)
Dave Barach68b0fb02017-02-28 15:15:56 -050071{
72 u8 wnd_scale = 0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -040073 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
Dave Barach68b0fb02017-02-28 15:15:56 -050074 wnd_scale++;
75 return wnd_scale;
76}
77
78/**
Florin Coras6534b7a2017-07-18 05:38:03 -040079 * TCP's initial window
Florin Corase04c2992017-03-01 08:17:34 -080080 */
81always_inline u32
82tcp_initial_wnd_unscaled (tcp_connection_t * tc)
83{
Florin Coras6534b7a2017-07-18 05:38:03 -040084 /* RFC 6928 recommends the value lower. However at the time our connections
85 * are initialized, fifos may not be allocated. Therefore, advertise the
86 * smallest possible unscaled window size and update once fifos are
87 * assigned to the session.
88 */
89 /*
90 tcp_update_rcv_mss (tc);
91 TCP_IW_N_SEGMENTS * tc->mss;
92 */
Florin Coras9094b5c2019-08-12 14:17:47 -070093 return tcp_cfg.min_rx_fifo;
Florin Corase04c2992017-03-01 08:17:34 -080094}
95
96/**
Dave Barach68b0fb02017-02-28 15:15:56 -050097 * Compute initial window and scale factor. As per RFC1323, window field in
98 * SYN and SYN-ACK segments is never scaled.
99 */
100u32
101tcp_initial_window_to_advertise (tcp_connection_t * tc)
102{
Florin Corase80b5912018-12-12 19:25:43 -0800103 /* Compute rcv wscale only if peer advertised support for it */
104 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
Florin Coras9094b5c2019-08-12 14:17:47 -0700105 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
Florin Corase80b5912018-12-12 19:25:43 -0800106
Florin Corase04c2992017-03-01 08:17:34 -0800107 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500108
109 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
110}
111
Florin Corasf20fd1a2019-03-28 13:21:19 -0700112static inline void
Florin Coras6792ec02017-03-13 03:49:51 -0700113tcp_update_rcv_wnd (tcp_connection_t * tc)
114{
Florin Corasf20fd1a2019-03-28 13:21:19 -0700115 u32 available_space, wnd;
Florin Coras6792ec02017-03-13 03:49:51 -0700116 i32 observed_wnd;
Florin Corasf20fd1a2019-03-28 13:21:19 -0700117
118 ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection));
Florin Coras6792ec02017-03-13 03:49:51 -0700119
Florin Corase04c2992017-03-01 08:17:34 -0800120 /*
121 * Figure out how much space we have available
122 */
Florin Corasd2aab832018-05-22 11:39:59 -0700123 available_space = transport_max_rx_enqueue (&tc->connection);
Florin Corasf20fd1a2019-03-28 13:21:19 -0700124 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
Florin Coras182d2192019-07-24 10:27:20 -0700125 {
126 tc->rcv_wnd = 0;
127 return;
128 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500129
Florin Corase04c2992017-03-01 08:17:34 -0800130 /*
131 * Use the above and what we know about what we've previously advertised
132 * to compute the new window
133 */
Florin Coras6792ec02017-03-13 03:49:51 -0700134 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
Florin Corase04c2992017-03-01 08:17:34 -0800135
136 /* Bad. Thou shalt not shrink */
Florin Corasf20fd1a2019-03-28 13:21:19 -0700137 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
Florin Corase04c2992017-03-01 08:17:34 -0800138 {
Florin Corasf20fd1a2019-03-28 13:21:19 -0700139 wnd = clib_max (observed_wnd, 0);
Florin Corasa436a422019-08-20 07:09:31 -0700140 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
Florin Corase04c2992017-03-01 08:17:34 -0800141 }
Florin Coras6792ec02017-03-13 03:49:51 -0700142 else
Florin Corase04c2992017-03-01 08:17:34 -0800143 {
Florin Coras6792ec02017-03-13 03:49:51 -0700144 wnd = available_space;
Florin Corase04c2992017-03-01 08:17:34 -0800145 }
146
Florin Coras3e350af2017-03-30 02:54:28 -0700147 /* Make sure we have a multiple of rcv_wscale */
148 if (wnd && tc->rcv_wscale)
149 {
Florin Coras679b78f2019-03-06 21:16:26 -0800150 wnd &= ~((1 << tc->rcv_wscale) - 1);
Florin Coras3e350af2017-03-30 02:54:28 -0700151 if (wnd == 0)
152 wnd = 1 << tc->rcv_wscale;
153 }
Florin Coras6792ec02017-03-13 03:49:51 -0700154
155 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
Dave Barach68b0fb02017-02-28 15:15:56 -0500156}
157
158/**
Florin Coras0dbd5172018-06-25 16:19:34 -0700159 * Compute and return window to advertise, scaled as per RFC1323
160 */
Florin Coras47596832019-03-12 18:58:54 -0700161static inline u32
Florin Coras0dbd5172018-06-25 16:19:34 -0700162tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
163{
164 if (state < TCP_STATE_ESTABLISHED)
165 return tcp_initial_window_to_advertise (tc);
166
167 tcp_update_rcv_wnd (tc);
Florin Coras0dbd5172018-06-25 16:19:34 -0700168 return tc->rcv_wnd >> tc->rcv_wscale;
169}
170
171/**
Dave Barach68b0fb02017-02-28 15:15:56 -0500172 * Write TCP options to segment.
173 */
Florin Coras0dbd5172018-06-25 16:19:34 -0700174static u32
Dave Barach68b0fb02017-02-28 15:15:56 -0500175tcp_options_write (u8 * data, tcp_options_t * opts)
176{
177 u32 opts_len = 0;
178 u32 buf, seq_len = 4;
179
180 if (tcp_opts_mss (opts))
181 {
182 *data++ = TCP_OPTION_MSS;
183 *data++ = TCP_OPTION_LEN_MSS;
184 buf = clib_host_to_net_u16 (opts->mss);
Dave Barach178cf492018-11-13 16:34:13 -0500185 clib_memcpy_fast (data, &buf, sizeof (opts->mss));
Dave Barach68b0fb02017-02-28 15:15:56 -0500186 data += sizeof (opts->mss);
187 opts_len += TCP_OPTION_LEN_MSS;
188 }
189
190 if (tcp_opts_wscale (opts))
191 {
192 *data++ = TCP_OPTION_WINDOW_SCALE;
193 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
194 *data++ = opts->wscale;
195 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
196 }
197
198 if (tcp_opts_sack_permitted (opts))
199 {
200 *data++ = TCP_OPTION_SACK_PERMITTED;
201 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
202 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
203 }
204
205 if (tcp_opts_tstamp (opts))
206 {
207 *data++ = TCP_OPTION_TIMESTAMP;
208 *data++ = TCP_OPTION_LEN_TIMESTAMP;
209 buf = clib_host_to_net_u32 (opts->tsval);
Dave Barach178cf492018-11-13 16:34:13 -0500210 clib_memcpy_fast (data, &buf, sizeof (opts->tsval));
Dave Barach68b0fb02017-02-28 15:15:56 -0500211 data += sizeof (opts->tsval);
212 buf = clib_host_to_net_u32 (opts->tsecr);
Dave Barach178cf492018-11-13 16:34:13 -0500213 clib_memcpy_fast (data, &buf, sizeof (opts->tsecr));
Dave Barach68b0fb02017-02-28 15:15:56 -0500214 data += sizeof (opts->tsecr);
215 opts_len += TCP_OPTION_LEN_TIMESTAMP;
216 }
217
218 if (tcp_opts_sack (opts))
219 {
220 int i;
Dave Barach68b0fb02017-02-28 15:15:56 -0500221
Florin Corase5b17912019-02-21 16:46:24 -0800222 if (opts->n_sack_blocks != 0)
Dave Barach68b0fb02017-02-28 15:15:56 -0500223 {
224 *data++ = TCP_OPTION_SACK_BLOCK;
Florin Corase5b17912019-02-21 16:46:24 -0800225 *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
226 for (i = 0; i < opts->n_sack_blocks; i++)
Dave Barach68b0fb02017-02-28 15:15:56 -0500227 {
228 buf = clib_host_to_net_u32 (opts->sacks[i].start);
Dave Barach178cf492018-11-13 16:34:13 -0500229 clib_memcpy_fast (data, &buf, seq_len);
Dave Barach68b0fb02017-02-28 15:15:56 -0500230 data += seq_len;
231 buf = clib_host_to_net_u32 (opts->sacks[i].end);
Dave Barach178cf492018-11-13 16:34:13 -0500232 clib_memcpy_fast (data, &buf, seq_len);
Dave Barach68b0fb02017-02-28 15:15:56 -0500233 data += seq_len;
234 }
Florin Corase5b17912019-02-21 16:46:24 -0800235 opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
Dave Barach68b0fb02017-02-28 15:15:56 -0500236 }
237 }
238
239 /* Terminate TCP options */
240 if (opts_len % 4)
241 {
242 *data++ = TCP_OPTION_EOL;
243 opts_len += TCP_OPTION_LEN_EOL;
244 }
245
246 /* Pad with zeroes to a u32 boundary */
247 while (opts_len % 4)
248 {
249 *data++ = TCP_OPTION_NOOP;
250 opts_len += TCP_OPTION_LEN_NOOP;
251 }
252 return opts_len;
253}
254
Florin Coras0dbd5172018-06-25 16:19:34 -0700255static int
Florin Corascedcf602019-08-27 12:15:43 -0700256tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
Dave Barach68b0fb02017-02-28 15:15:56 -0500257{
258 u8 len = 0;
259
260 opts->flags |= TCP_OPTS_FLAG_MSS;
Florin Corascedcf602019-08-27 12:15:43 -0700261 opts->mss = tc->mss;
Dave Barach68b0fb02017-02-28 15:15:56 -0500262 len += TCP_OPTION_LEN_MSS;
263
264 opts->flags |= TCP_OPTS_FLAG_WSCALE;
Florin Corascedcf602019-08-27 12:15:43 -0700265 opts->wscale = tc->rcv_wscale;
Dave Barach68b0fb02017-02-28 15:15:56 -0500266 len += TCP_OPTION_LEN_WINDOW_SCALE;
267
268 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
269 opts->tsval = tcp_time_now ();
270 opts->tsecr = 0;
271 len += TCP_OPTION_LEN_TIMESTAMP;
272
Florin Coras93992a92017-05-24 18:03:56 -0700273 if (TCP_USE_SACKS)
274 {
275 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
276 len += TCP_OPTION_LEN_SACK_PERMITTED;
277 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500278
279 /* Align to needed boundary */
280 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
281 return len;
282}
283
Florin Coras0dbd5172018-06-25 16:19:34 -0700284static int
Dave Barach68b0fb02017-02-28 15:15:56 -0500285tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
286{
287 u8 len = 0;
288
289 opts->flags |= TCP_OPTS_FLAG_MSS;
Florin Corasc8343412017-05-04 14:25:50 -0700290 opts->mss = tc->mss;
Dave Barach68b0fb02017-02-28 15:15:56 -0500291 len += TCP_OPTION_LEN_MSS;
292
Florin Coras93992a92017-05-24 18:03:56 -0700293 if (tcp_opts_wscale (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500294 {
295 opts->flags |= TCP_OPTS_FLAG_WSCALE;
296 opts->wscale = tc->rcv_wscale;
297 len += TCP_OPTION_LEN_WINDOW_SCALE;
298 }
299
Florin Coras93992a92017-05-24 18:03:56 -0700300 if (tcp_opts_tstamp (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500301 {
302 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
303 opts->tsval = tcp_time_now ();
304 opts->tsecr = tc->tsval_recent;
305 len += TCP_OPTION_LEN_TIMESTAMP;
306 }
307
Florin Coras93992a92017-05-24 18:03:56 -0700308 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500309 {
310 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
311 len += TCP_OPTION_LEN_SACK_PERMITTED;
312 }
313
314 /* Align to needed boundary */
315 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
316 return len;
317}
318
Florin Coras0dbd5172018-06-25 16:19:34 -0700319static int
Dave Barach68b0fb02017-02-28 15:15:56 -0500320tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
321{
322 u8 len = 0;
323
324 opts->flags = 0;
325
Florin Coras93992a92017-05-24 18:03:56 -0700326 if (tcp_opts_tstamp (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500327 {
328 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
Vladimir Kropylev1cfcb782019-07-02 11:25:26 +0300329 opts->tsval = tcp_tstamp (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500330 opts->tsecr = tc->tsval_recent;
331 len += TCP_OPTION_LEN_TIMESTAMP;
332 }
Florin Coras93992a92017-05-24 18:03:56 -0700333 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500334 {
335 if (vec_len (tc->snd_sacks))
336 {
337 opts->flags |= TCP_OPTS_FLAG_SACK;
Florin Corase5b17912019-02-21 16:46:24 -0800338 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
339 tc->snd_sack_pos = 0;
340 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
341 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
342 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
Florin Corasc28764f2017-04-26 00:08:42 -0700343 TCP_OPTS_MAX_SACK_BLOCKS);
Florin Corase5b17912019-02-21 16:46:24 -0800344 tc->snd_sack_pos += opts->n_sack_blocks;
Dave Barach68b0fb02017-02-28 15:15:56 -0500345 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
346 }
347 }
348
349 /* Align to needed boundary */
350 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
351 return len;
352}
353
354always_inline int
355tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
356 tcp_state_t state)
357{
358 switch (state)
359 {
360 case TCP_STATE_ESTABLISHED:
Florin Coras25579b42018-06-06 17:55:02 -0700361 case TCP_STATE_CLOSE_WAIT:
Florin Coras54ddf432018-12-21 13:54:09 -0800362 case TCP_STATE_FIN_WAIT_1:
363 case TCP_STATE_LAST_ACK:
364 case TCP_STATE_CLOSING:
365 case TCP_STATE_FIN_WAIT_2:
366 case TCP_STATE_TIME_WAIT:
367 case TCP_STATE_CLOSED:
Dave Barach68b0fb02017-02-28 15:15:56 -0500368 return tcp_make_established_options (tc, opts);
369 case TCP_STATE_SYN_RCVD:
370 return tcp_make_synack_options (tc, opts);
371 case TCP_STATE_SYN_SENT:
Florin Corascedcf602019-08-27 12:15:43 -0700372 return tcp_make_syn_options (tc, opts);
Dave Barach68b0fb02017-02-28 15:15:56 -0500373 default:
Florin Coras371ca502018-02-21 12:07:41 -0800374 clib_warning ("State not handled! %d", state);
Dave Barach68b0fb02017-02-28 15:15:56 -0500375 return 0;
376 }
377}
378
Florin Corasc8343412017-05-04 14:25:50 -0700379/**
Florin Corasb26743d2018-06-26 09:31:04 -0700380 * Update burst send vars
381 *
382 * - Updates snd_mss to reflect the effective segment size that we can send
383 * by taking into account all TCP options, including SACKs.
384 * - Cache 'on the wire' options for reuse
385 * - Updates receive window which can be reused for a burst.
386 *
387 * This should *only* be called when doing bursts
Florin Corasc8343412017-05-04 14:25:50 -0700388 */
389void
Florin Corasb26743d2018-06-26 09:31:04 -0700390tcp_update_burst_snd_vars (tcp_connection_t * tc)
Florin Corasc8343412017-05-04 14:25:50 -0700391{
Florin Corasb26743d2018-06-26 09:31:04 -0700392 tcp_main_t *tm = &tcp_main;
393
Florin Corasc8343412017-05-04 14:25:50 -0700394 /* Compute options to be used for connection. These may be reused when
395 * sending data or to compute the effective mss (snd_mss) */
Florin Corasb26743d2018-06-26 09:31:04 -0700396 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
397 TCP_STATE_ESTABLISHED);
Florin Corasc8343412017-05-04 14:25:50 -0700398
399 /* XXX check if MTU has been updated */
Florin Coras93992a92017-05-24 18:03:56 -0700400 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
Florin Corasdb84e572017-05-09 18:54:52 -0700401 ASSERT (tc->snd_mss > 0);
Florin Corasb26743d2018-06-26 09:31:04 -0700402
403 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
404 &tc->snd_opts);
405
406 tcp_update_rcv_wnd (tc);
Florin Coras52814732019-06-12 15:38:19 -0700407
Florin Corasbbcfaac2019-10-10 13:52:04 -0700408 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Corasd6ae4bf2019-10-12 18:10:20 -0700409 tcp_bt_check_app_limited (tc);
Florin Corasca2831a2019-07-04 17:05:59 -0700410
411 if (tc->snd_una == tc->snd_nxt)
Florin Corasc31dc312019-10-06 14:06:14 -0700412 {
413 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
Florin Coras11e9e352019-11-13 19:09:47 -0800414 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST);
Florin Corasc31dc312019-10-06 14:06:14 -0700415 }
Florin Corasc8343412017-05-04 14:25:50 -0700416}
417
Filip Tehlare275bed2019-03-06 00:06:56 -0800418#endif /* CLIB_MARCH_VARIANT */
Florin Corasc8343412017-05-04 14:25:50 -0700419
Florin Coras0dbd5172018-06-25 16:19:34 -0700420static void *
Dave Barach68b0fb02017-02-28 15:15:56 -0500421tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
422{
Florin Corasb2215d62017-08-01 16:56:58 -0700423 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
424 vlib_buffer_free_one (vm, b->next_buffer);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400425 /* Zero all flags but free list index and trace flag */
426 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
Florin Coras1f152cd2017-08-18 19:28:03 -0700427 b->current_data = 0;
428 b->current_length = 0;
429 b->total_length_not_including_first_buffer = 0;
430 vnet_buffer (b)->tcp.flags = 0;
Florin Corasb2215d62017-08-01 16:56:58 -0700431
Dave Barach68b0fb02017-02-28 15:15:56 -0500432 /* Leave enough space for headers */
Florin Coras1ee78302019-02-05 15:51:15 -0800433 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
Florin Coras1f152cd2017-08-18 19:28:03 -0700434}
435
Filip Tehlare275bed2019-03-06 00:06:56 -0800436#ifndef CLIB_MARCH_VARIANT
Florin Coras0dbd5172018-06-25 16:19:34 -0700437static void *
Florin Coras1f152cd2017-08-18 19:28:03 -0700438tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
439{
440 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400441 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
Florin Coras1f152cd2017-08-18 19:28:03 -0700442 b->total_length_not_including_first_buffer = 0;
Florin Coras24793e32018-05-09 11:34:25 -0700443 b->current_data = 0;
Florin Corasd79b41e2017-03-04 05:37:52 -0800444 vnet_buffer (b)->tcp.flags = 0;
Florin Corasf988e692017-11-27 04:34:14 -0500445 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
Florin Coras1f152cd2017-08-18 19:28:03 -0700446 /* Leave enough space for headers */
Florin Coras1ee78302019-02-05 15:51:15 -0800447 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
Dave Barach68b0fb02017-02-28 15:15:56 -0500448}
449
Srikanth A02833ff2019-10-02 17:48:58 -0700450
451/* Compute TCP checksum in software when offloading is disabled for a connection */
452u16
453ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
454 ip46_address_t * src, ip46_address_t * dst)
455{
456 ip_csum_t sum0;
457 u16 payload_length_host_byte_order;
458 u32 i;
459
460 /* Initialize checksum with ip header. */
461 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
462 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
463 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
464
465 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
466 {
467 sum0 = ip_csum_with_carry
468 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
469 sum0 = ip_csum_with_carry
470 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
471 }
472
473 return ip_calculate_l4_checksum (vm, p0, sum0,
474 payload_length_host_byte_order, NULL, 0,
475 NULL);
476}
477
478u16
479ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
480 ip46_address_t * src, ip46_address_t * dst)
481{
482 ip_csum_t sum0;
483 u32 payload_length_host_byte_order;
484
485 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
486 sum0 =
487 clib_host_to_net_u32 (payload_length_host_byte_order +
488 (IP_PROTOCOL_TCP << 16));
489
490 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
491 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
492
493 return ip_calculate_l4_checksum (vm, p0, sum0,
494 payload_length_host_byte_order, NULL, 0,
495 NULL);
496}
497
498static inline u16
499tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
500{
501 u16 checksum = 0;
Florin Corasbbcfaac2019-10-10 13:52:04 -0700502 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
Srikanth A02833ff2019-10-02 17:48:58 -0700503 {
504 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
505 vlib_main_t *vm = wrk->vm;
506
507 if (tc->c_is_ip4)
508 checksum = ip4_tcp_compute_checksum_custom
509 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
510 else
511 checksum = ip6_tcp_compute_checksum_custom
512 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
513 }
514 else
515 {
516 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
517 }
518 return checksum;
519}
520
Dave Barach68b0fb02017-02-28 15:15:56 -0500521/**
522 * Prepare ACK
523 */
Florin Corasbdf7fd62019-01-31 17:31:01 -0800524static inline void
Dave Barach68b0fb02017-02-28 15:15:56 -0500525tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
526 u8 flags)
527{
528 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
529 u8 tcp_opts_len, tcp_hdr_opts_len;
530 tcp_header_t *th;
531 u16 wnd;
532
533 wnd = tcp_window_to_advertise (tc, state);
534
535 /* Make and write options */
536 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
537 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
538
539 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
540 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
541
542 tcp_options_write ((u8 *) (th + 1), snd_opts);
Srikanth A02833ff2019-10-02 17:48:58 -0700543
544 th->checksum = tcp_compute_checksum (tc, b);
545
Dave Barach68b0fb02017-02-28 15:15:56 -0500546 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Vladimir Kropylev398afbd2019-06-25 00:06:52 +0300547
548 if (wnd == 0)
549 tcp_zero_rwnd_sent_on (tc);
550 else
551 tcp_zero_rwnd_sent_off (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500552}
553
554/**
555 * Convert buffer to ACK
556 */
Florin Corasbdf7fd62019-01-31 17:31:01 -0800557static inline void
Dave Barach68b0fb02017-02-28 15:15:56 -0500558tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
559{
Dave Barach68b0fb02017-02-28 15:15:56 -0500560 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
Florin Corasa436a422019-08-20 07:09:31 -0700561 TCP_EVT (TCP_EVT_ACK_SENT, tc);
Florin Coras3e350af2017-03-30 02:54:28 -0700562 tc->rcv_las = tc->rcv_nxt;
Dave Barach68b0fb02017-02-28 15:15:56 -0500563}
564
565/**
566 * Convert buffer to FIN-ACK
567 */
568void
Florin Corasd79b41e2017-03-04 05:37:52 -0800569tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
Dave Barach68b0fb02017-02-28 15:15:56 -0500570{
Florin Corasbdf7fd62019-01-31 17:31:01 -0800571 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400572}
Dave Barach68b0fb02017-02-28 15:15:56 -0500573
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400574/**
575 * Convert buffer to SYN
576 */
577void
578tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
579{
580 u8 tcp_hdr_opts_len, tcp_opts_len;
581 tcp_header_t *th;
582 u16 initial_wnd;
583 tcp_options_t snd_opts;
584
585 initial_wnd = tcp_initial_window_to_advertise (tc);
586
587 /* Make and write options */
Dave Barachb7b92992018-10-17 10:38:51 -0400588 clib_memset (&snd_opts, 0, sizeof (snd_opts));
Florin Corascedcf602019-08-27 12:15:43 -0700589 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400590 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
591
592 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
593 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
594 initial_wnd);
595 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
596 tcp_options_write ((u8 *) (th + 1), &snd_opts);
Srikanth A02833ff2019-10-02 17:48:58 -0700597 th->checksum = tcp_compute_checksum (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500598}
599
600/**
601 * Convert buffer to SYN-ACK
602 */
603void
604tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
605{
Dave Barach68b0fb02017-02-28 15:15:56 -0500606 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
607 u8 tcp_opts_len, tcp_hdr_opts_len;
608 tcp_header_t *th;
609 u16 initial_wnd;
Dave Barach68b0fb02017-02-28 15:15:56 -0500610
Dave Barachb7b92992018-10-17 10:38:51 -0400611 clib_memset (snd_opts, 0, sizeof (*snd_opts));
Dave Barach68b0fb02017-02-28 15:15:56 -0500612 initial_wnd = tcp_initial_window_to_advertise (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500613 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
614 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
615
616 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
617 tc->rcv_nxt, tcp_hdr_opts_len,
618 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
Dave Barach68b0fb02017-02-28 15:15:56 -0500619 tcp_options_write ((u8 *) (th + 1), snd_opts);
620
621 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Srikanth A02833ff2019-10-02 17:48:58 -0700622 th->checksum = tcp_compute_checksum (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500623}
624
625always_inline void
Florin Corasbe72ae62018-11-01 11:23:03 -0700626tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
Florin Coras56b39f62018-03-27 17:29:32 -0700627 u8 is_ip4, u32 fib_index, u8 flush)
Dave Barach68b0fb02017-02-28 15:15:56 -0500628{
Florin Corasbe72ae62018-11-01 11:23:03 -0700629 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -0500630 u32 *to_next, next_index;
631 vlib_frame_t *f;
632
Damjan Marion213b5aa2017-07-13 21:19:27 +0200633 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
Dave Barach68b0fb02017-02-28 15:15:56 -0500634 b->error = 0;
635
Florin Coras56b39f62018-03-27 17:29:32 -0700636 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
637 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500638
639 /* Send to IP lookup */
640 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
Florin Corasf988e692017-11-27 04:34:14 -0500641 tcp_trajectory_add_start (b, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500642
Florin Corasbe72ae62018-11-01 11:23:03 -0700643 f = wrk->ip_lookup_tx_frames[!is_ip4];
Florin Coras9d063042017-09-14 03:08:00 -0400644 if (!f)
645 {
646 f = vlib_get_frame_to_node (vm, next_index);
647 ASSERT (f);
Florin Corasbe72ae62018-11-01 11:23:03 -0700648 wrk->ip_lookup_tx_frames[!is_ip4] = f;
Florin Coras9d063042017-09-14 03:08:00 -0400649 }
650
Dave Barach68b0fb02017-02-28 15:15:56 -0500651 to_next = vlib_frame_vector_args (f);
Florin Coras9d063042017-09-14 03:08:00 -0400652 to_next[f->n_vectors] = bi;
653 f->n_vectors += 1;
654 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
655 {
656 vlib_put_frame_to_node (vm, next_index, f);
Florin Corasbe72ae62018-11-01 11:23:03 -0700657 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
Florin Coras9d063042017-09-14 03:08:00 -0400658 }
659}
660
Florin Coras0dbd5172018-06-25 16:19:34 -0700661static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700662tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b,
663 u32 bi, u8 is_ip4, u32 fib_index)
Florin Coras9d063042017-09-14 03:08:00 -0400664{
Florin Corasbe72ae62018-11-01 11:23:03 -0700665 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1);
Florin Coras9d063042017-09-14 03:08:00 -0400666}
667
Florin Coras0dbd5172018-06-25 16:19:34 -0700668static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700669tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
Florin Coras56b39f62018-03-27 17:29:32 -0700670 u8 is_ip4, u32 fib_index)
Florin Coras9d063042017-09-14 03:08:00 -0400671{
Florin Corasbe72ae62018-11-01 11:23:03 -0700672 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0);
673 if (wrk->vm->thread_index == 0 && vlib_num_workers ())
674 session_flush_frames_main_thread (wrk->vm);
Dave Barach68b0fb02017-02-28 15:15:56 -0500675}
676
Florin Coras0dbd5172018-06-25 16:19:34 -0700677static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700678tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
679 u8 is_ip4)
Florin Coras1f152cd2017-08-18 19:28:03 -0700680{
Florin Coras2a7ea2e2019-10-16 22:06:08 -0700681 session_type_t st;
682
683 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
684 b->error = 0;
685
686 st = session_type_from_proto_and_ip (TRANSPORT_PROTO_TCP, is_ip4);
687 session_add_pending_tx_buffer (st, wrk->vm->thread_index, bi);
Florin Coras1f152cd2017-08-18 19:28:03 -0700688}
689
Filip Tehlare275bed2019-03-06 00:06:56 -0800690#endif /* CLIB_MARCH_VARIANT */
Florin Coras1f152cd2017-08-18 19:28:03 -0700691
Florin Coras0dbd5172018-06-25 16:19:34 -0700692static int
Dave Barach68b0fb02017-02-28 15:15:56 -0500693tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
Florin Corasdc629cd2017-05-09 00:52:37 -0700694 tcp_state_t state, u8 thread_index, u8 is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -0500695{
Dave Barach68b0fb02017-02-28 15:15:56 -0500696 ip4_header_t *ih4;
697 ip6_header_t *ih6;
698 tcp_header_t *th0;
Florin Corasdc629cd2017-05-09 00:52:37 -0700699 ip4_address_t src_ip40, dst_ip40;
700 ip6_address_t src_ip60, dst_ip60;
701 u16 src_port, dst_port;
Dave Barach68b0fb02017-02-28 15:15:56 -0500702 u32 tmp;
Florin Corasdc629cd2017-05-09 00:52:37 -0700703 u32 seq, ack;
704 u8 flags;
Dave Barach68b0fb02017-02-28 15:15:56 -0500705
706 /* Find IP and TCP headers */
Florin Corasdc629cd2017-05-09 00:52:37 -0700707 th0 = tcp_buffer_hdr (b0);
708
709 /* Save src and dst ip */
Dave Barach68b0fb02017-02-28 15:15:56 -0500710 if (is_ip4)
711 {
712 ih4 = vlib_buffer_get_current (b0);
Florin Corasdc629cd2017-05-09 00:52:37 -0700713 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
714 src_ip40.as_u32 = ih4->src_address.as_u32;
715 dst_ip40.as_u32 = ih4->dst_address.as_u32;
Dave Barach68b0fb02017-02-28 15:15:56 -0500716 }
717 else
718 {
719 ih6 = vlib_buffer_get_current (b0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500720 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
Dave Barach178cf492018-11-13 16:34:13 -0500721 clib_memcpy_fast (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
722 clib_memcpy_fast (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
Dave Barach68b0fb02017-02-28 15:15:56 -0500723 }
724
Florin Corasdc629cd2017-05-09 00:52:37 -0700725 src_port = th0->src_port;
726 dst_port = th0->dst_port;
727
728 /* Try to determine what/why we're actually resetting */
Dave Barach68b0fb02017-02-28 15:15:56 -0500729 if (state == TCP_STATE_CLOSED)
730 {
731 if (!tcp_syn (th0))
732 return -1;
733
734 tmp = clib_net_to_host_u32 (th0->seq_number);
735
736 /* Got a SYN for no listener. */
Florin Corasdc629cd2017-05-09 00:52:37 -0700737 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
738 ack = clib_host_to_net_u32 (tmp + 1);
739 seq = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500740 }
Florin Corasdc629cd2017-05-09 00:52:37 -0700741 else
Dave Barach68b0fb02017-02-28 15:15:56 -0500742 {
Florin Corasdc629cd2017-05-09 00:52:37 -0700743 flags = TCP_FLAG_RST;
744 seq = th0->ack_number;
745 ack = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500746 }
747
Florin Corasdc629cd2017-05-09 00:52:37 -0700748 tcp_reuse_buffer (vm, b0);
Florin Corasf988e692017-11-27 04:34:14 -0500749 tcp_trajectory_add_start (b0, 4);
Florin Corasdc629cd2017-05-09 00:52:37 -0700750 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
751 sizeof (tcp_header_t), flags, 0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500752
Dave Barach68b0fb02017-02-28 15:15:56 -0500753 if (is_ip4)
754 {
Florin Corasdc629cd2017-05-09 00:52:37 -0700755 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
Florin Corasfdbc3822017-07-27 00:34:12 -0700756 IP_PROTOCOL_TCP, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500757 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
758 }
759 else
760 {
761 int bogus = ~0;
Florin Corasdc629cd2017-05-09 00:52:37 -0700762 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
763 IP_PROTOCOL_TCP);
Dave Barach68b0fb02017-02-28 15:15:56 -0500764 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
765 ASSERT (!bogus);
766 }
767
768 return 0;
769}
770
Filip Tehlare275bed2019-03-06 00:06:56 -0800771#ifndef CLIB_MARCH_VARIANT
Dave Barach68b0fb02017-02-28 15:15:56 -0500772/**
773 * Send reset without reusing existing buffer
Florin Coras1f152cd2017-08-18 19:28:03 -0700774 *
775 * It extracts connection info out of original packet
Dave Barach68b0fb02017-02-28 15:15:56 -0500776 */
777void
Florin Corasd4c49be2019-02-07 00:15:53 -0800778tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
779 u32 thread_index, u8 is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -0500780{
Florin Corasd4c49be2019-02-07 00:15:53 -0800781 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
Florin Corasbe72ae62018-11-01 11:23:03 -0700782 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -0500783 vlib_buffer_t *b;
Florin Coras56b39f62018-03-27 17:29:32 -0700784 u32 bi, sw_if_index, fib_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500785 u8 tcp_hdr_len, flags = 0;
786 tcp_header_t *th, *pkt_th;
787 u32 seq, ack;
788 ip4_header_t *ih4, *pkt_ih4;
789 ip6_header_t *ih6, *pkt_ih6;
Florin Coras56b39f62018-03-27 17:29:32 -0700790 fib_protocol_t fib_proto;
Dave Barach68b0fb02017-02-28 15:15:56 -0500791
Florin Corasbdf7fd62019-01-31 17:31:01 -0800792 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras66b11312017-07-31 17:18:03 -0700793 return;
794
Dave Barach68b0fb02017-02-28 15:15:56 -0500795 b = vlib_get_buffer (vm, bi);
Florin Coras56b39f62018-03-27 17:29:32 -0700796 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
797 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
798 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
Florin Coras1f152cd2017-08-18 19:28:03 -0700799 tcp_init_buffer (vm, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500800
801 /* Make and write options */
802 tcp_hdr_len = sizeof (tcp_header_t);
803
804 if (is_ip4)
805 {
806 pkt_ih4 = vlib_buffer_get_current (pkt);
807 pkt_th = ip4_next_header (pkt_ih4);
808 }
809 else
810 {
811 pkt_ih6 = vlib_buffer_get_current (pkt);
812 pkt_th = ip6_next_header (pkt_ih6);
813 }
814
815 if (tcp_ack (pkt_th))
816 {
817 flags = TCP_FLAG_RST;
818 seq = pkt_th->ack_number;
Florin Coras776f3d82018-11-02 08:23:58 -0700819 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500820 }
821 else
822 {
823 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
824 seq = 0;
825 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
826 }
827
828 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
829 seq, ack, tcp_hdr_len, flags, 0);
830
831 /* Swap src and dst ip */
832 if (is_ip4)
833 {
834 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
835 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
Srikanth A02833ff2019-10-02 17:48:58 -0700836 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
Florin Corasbbcfaac2019-10-10 13:52:04 -0700837 tcp_csum_offload (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500838 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
839 }
840 else
841 {
842 int bogus = ~0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500843 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
844 0x60);
Tarun Gupta2089c692019-11-04 16:35:59 -0800845 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
846 &pkt_ih6->src_address,
847 IP_PROTOCOL_TCP,
848 tc->ipv6_flow_label);
Dave Barach68b0fb02017-02-28 15:15:56 -0500849 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
850 ASSERT (!bogus);
851 }
852
Florin Corasbe72ae62018-11-01 11:23:03 -0700853 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index);
Florin Corasa436a422019-08-20 07:09:31 -0700854 TCP_EVT (TCP_EVT_RST_SENT, tc);
Florin Coras1f421012019-07-26 10:18:51 -0700855 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
856 TCP_ERROR_RST_SENT, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500857}
858
Florin Coras1f152cd2017-08-18 19:28:03 -0700859/**
860 * Build and set reset packet for connection
861 */
862void
863tcp_send_reset (tcp_connection_t * tc)
864{
Florin Corasbe72ae62018-11-01 11:23:03 -0700865 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
866 vlib_main_t *vm = wrk->vm;
Florin Coras1f152cd2017-08-18 19:28:03 -0700867 vlib_buffer_t *b;
868 u32 bi;
869 tcp_header_t *th;
870 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
871 u8 flags;
872
Florin Corasbdf7fd62019-01-31 17:31:01 -0800873 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras1f152cd2017-08-18 19:28:03 -0700874 return;
875 b = vlib_get_buffer (vm, bi);
876 tcp_init_buffer (vm, b);
877
878 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
879 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
880 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
881 flags = TCP_FLAG_RST;
882 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
883 tc->rcv_nxt, tcp_hdr_opts_len, flags,
884 advertise_wnd);
885 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
Srikanth A02833ff2019-10-02 17:48:58 -0700886 th->checksum = tcp_compute_checksum (tc, b);
Florin Coras1f152cd2017-08-18 19:28:03 -0700887 ASSERT (opts_write_len == tc->snd_opts_len);
888 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Florin Corasdf36f492019-08-18 18:09:28 -0700889 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasa436a422019-08-20 07:09:31 -0700890 TCP_EVT (TCP_EVT_RST_SENT, tc);
Florin Coras1f421012019-07-26 10:18:51 -0700891 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
892 TCP_ERROR_RST_SENT, 1);
Florin Coras1f152cd2017-08-18 19:28:03 -0700893}
894
Florin Coras0dbd5172018-06-25 16:19:34 -0700895static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700896tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
897 vlib_buffer_t * b)
Dave Barach68b0fb02017-02-28 15:15:56 -0500898{
Dave Barach68b0fb02017-02-28 15:15:56 -0500899 if (tc->c_is_ip4)
900 {
Florin Corasf4ce6ba2019-11-20 18:34:58 -0800901 vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4,
902 IP_PROTOCOL_TCP, tcp_csum_offload (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500903 }
904 else
905 {
Florin Corasf4ce6ba2019-11-20 18:34:58 -0800906 vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6,
907 IP_PROTOCOL_TCP, tc->ipv6_flow_label);
Dave Barach68b0fb02017-02-28 15:15:56 -0500908 }
909}
910
911/**
912 * Send SYN
913 *
914 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
915 * The packet is not forwarded through tcpx_output to avoid doing lookups
916 * in the half_open pool.
917 */
918void
919tcp_send_syn (tcp_connection_t * tc)
920{
Florin Corasbe72ae62018-11-01 11:23:03 -0700921 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
922 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -0500923 vlib_buffer_t *b;
924 u32 bi;
Dave Barach68b0fb02017-02-28 15:15:56 -0500925
Florin Corasf988e692017-11-27 04:34:14 -0500926 /*
927 * Setup retransmit and establish timers before requesting buffer
928 * such that we can return if we've ran out.
929 */
Florin Corasf988e692017-11-27 04:34:14 -0500930 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
931 tc->rto * TCP_TO_TIMER_TICK);
932
Florin Corasbdf7fd62019-01-31 17:31:01 -0800933 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras222e1f412019-02-16 20:47:32 -0800934 {
935 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
936 return;
937 }
Florin Coras66b11312017-07-31 17:18:03 -0700938
Dave Barach68b0fb02017-02-28 15:15:56 -0500939 b = vlib_get_buffer (vm, bi);
Florin Coras1f152cd2017-08-18 19:28:03 -0700940 tcp_init_buffer (vm, b);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400941 tcp_make_syn (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500942
943 /* Measure RTT with this */
Florin Corasefefc6b2018-11-07 12:49:19 -0800944 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500945 tc->rtt_seq = tc->snd_nxt;
Dave Barach68b0fb02017-02-28 15:15:56 -0500946 tc->rto_boff = 0;
947
Florin Corasbe72ae62018-11-01 11:23:03 -0700948 tcp_push_ip_hdr (wrk, tc, b);
949 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
Florin Corasa436a422019-08-20 07:09:31 -0700950 TCP_EVT (TCP_EVT_SYN_SENT, tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500951}
952
Florin Coras7ac053b2018-11-05 15:57:21 -0800953void
954tcp_send_synack (tcp_connection_t * tc)
955{
956 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
957 vlib_main_t *vm = wrk->vm;
958 vlib_buffer_t *b;
959 u32 bi;
960
Florin Coras222e1f412019-02-16 20:47:32 -0800961 tcp_retransmit_timer_force_update (tc);
962
Florin Corasbdf7fd62019-01-31 17:31:01 -0800963 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras222e1f412019-02-16 20:47:32 -0800964 {
965 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
966 return;
967 }
Florin Coras7ac053b2018-11-05 15:57:21 -0800968
Florin Corasdf084782018-12-06 17:41:10 -0800969 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -0800970 b = vlib_get_buffer (vm, bi);
Florin Corasbdf7fd62019-01-31 17:31:01 -0800971 tcp_init_buffer (vm, b);
Florin Coras7ac053b2018-11-05 15:57:21 -0800972 tcp_make_synack (tc, b);
973 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasa436a422019-08-20 07:09:31 -0700974 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
Florin Coras7ac053b2018-11-05 15:57:21 -0800975}
976
Florin Coras66b11312017-07-31 17:18:03 -0700977/**
Florin Coras9d063042017-09-14 03:08:00 -0400978 * Flush ip lookup tx frames populated by timer pops
979 */
Florin Coras0dbd5172018-06-25 16:19:34 -0700980static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700981tcp_flush_frame_to_ip_lookup (tcp_worker_ctx_t * wrk, u8 is_ip4)
Florin Coras9d063042017-09-14 03:08:00 -0400982{
Florin Corasbe72ae62018-11-01 11:23:03 -0700983 if (wrk->ip_lookup_tx_frames[!is_ip4])
Florin Coras9d063042017-09-14 03:08:00 -0400984 {
985 u32 next_index;
986 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
Florin Corasbe72ae62018-11-01 11:23:03 -0700987 vlib_put_frame_to_node (wrk->vm, next_index,
988 wrk->ip_lookup_tx_frames[!is_ip4]);
989 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
Florin Coras9d063042017-09-14 03:08:00 -0400990 }
991}
992
993/**
994 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
Florin Coras66b11312017-07-31 17:18:03 -0700995 */
996void
Florin Corasbe72ae62018-11-01 11:23:03 -0700997tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk)
Florin Coras66b11312017-07-31 17:18:03 -0700998{
Florin Corasbe72ae62018-11-01 11:23:03 -0700999 tcp_flush_frame_to_ip_lookup (wrk, 1);
1000 tcp_flush_frame_to_ip_lookup (wrk, 0);
Dave Barach68b0fb02017-02-28 15:15:56 -05001001}
1002
1003/**
1004 * Send FIN
1005 */
1006void
1007tcp_send_fin (tcp_connection_t * tc)
1008{
Florin Corasbe72ae62018-11-01 11:23:03 -07001009 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1010 vlib_main_t *vm = wrk->vm;
Florin Coras9d063042017-09-14 03:08:00 -04001011 vlib_buffer_t *b;
1012 u32 bi;
1013 u8 fin_snt = 0;
1014
Florin Corasc977e7c2018-10-16 20:30:31 -07001015 fin_snt = tc->flags & TCP_CONN_FINSNT;
1016 if (fin_snt)
Florin Coras47596832019-03-12 18:58:54 -07001017 tc->snd_nxt -= 1;
Florin Corasc977e7c2018-10-16 20:30:31 -07001018
Florin Corasbdf7fd62019-01-31 17:31:01 -08001019 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coraseb97e5f2018-10-15 21:35:42 -07001020 {
1021 /* Out of buffers so program fin retransmit ASAP */
1022 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
Florin Coras85a3ddd2018-12-24 16:54:34 -08001023 if (fin_snt)
Florin Coras47596832019-03-12 18:58:54 -07001024 tc->snd_nxt += 1;
Florin Coras222e1f412019-02-16 20:47:32 -08001025 else
1026 /* Make sure retransmit retries a fin not data */
1027 tc->flags |= TCP_CONN_FINSNT;
Florin Coras85a3ddd2018-12-24 16:54:34 -08001028 return;
Florin Coraseb97e5f2018-10-15 21:35:42 -07001029 }
1030
Florin Corascb711a42019-10-16 19:28:17 -07001031 /* If we have non-dupacks programmed, no need to send them */
1032 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
1033 tc->flags &= ~TCP_CONN_SNDACK;
1034
Florin Corasc977e7c2018-10-16 20:30:31 -07001035 tcp_retransmit_timer_force_update (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -05001036 b = vlib_get_buffer (vm, bi);
Florin Coras24793e32018-05-09 11:34:25 -07001037 tcp_init_buffer (vm, b);
Florin Corasd79b41e2017-03-04 05:37:52 -08001038 tcp_make_fin (tc, b);
Florin Coras2a7ea2e2019-10-16 22:06:08 -07001039 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasa436a422019-08-20 07:09:31 -07001040 TCP_EVT (TCP_EVT_FIN_SENT, tc);
Florin Coras47596832019-03-12 18:58:54 -07001041 /* Account for the FIN */
1042 tc->snd_nxt += 1;
Florin Coras9d063042017-09-14 03:08:00 -04001043 if (!fin_snt)
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001044 {
1045 tc->flags |= TCP_CONN_FINSNT;
1046 tc->flags &= ~TCP_CONN_FINPNDG;
Florin Coras47596832019-03-12 18:58:54 -07001047 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
Florin Corasa096f2d2017-09-28 23:49:42 -04001048 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001049}
1050
Dave Barach68b0fb02017-02-28 15:15:56 -05001051/**
Florin Corasfd247442019-03-12 16:56:26 -07001052 * Push TCP header and update connection variables. Should only be called
1053 * for segments with data, not for 'control' packets.
Dave Barach68b0fb02017-02-28 15:15:56 -05001054 */
Florin Coras0dbd5172018-06-25 16:19:34 -07001055always_inline void
Florin Coras47596832019-03-12 18:58:54 -07001056tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
1057 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
Dave Barach68b0fb02017-02-28 15:15:56 -05001058{
Florin Corasfd247442019-03-12 16:56:26 -07001059 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
Dave Barach68b0fb02017-02-28 15:15:56 -05001060 u32 advertise_wnd, data_len;
Florin Corasb26743d2018-06-26 09:31:04 -07001061 tcp_main_t *tm = &tcp_main;
Dave Barach68b0fb02017-02-28 15:15:56 -05001062 tcp_header_t *th;
1063
Florin Corasb26743d2018-06-26 09:31:04 -07001064 data_len = b->current_length;
1065 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1066 data_len += b->total_length_not_including_first_buffer;
1067
Dave Barach68b0fb02017-02-28 15:15:56 -05001068 vnet_buffer (b)->tcp.flags = 0;
Florin Corasb26743d2018-06-26 09:31:04 -07001069 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Dave Barach68b0fb02017-02-28 15:15:56 -05001070
Florin Corasc8343412017-05-04 14:25:50 -07001071 if (compute_opts)
1072 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1073
Florin Corasc8343412017-05-04 14:25:50 -07001074 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
Florin Corasb26743d2018-06-26 09:31:04 -07001075
1076 if (maybe_burst)
1077 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1078 else
Florin Coras47596832019-03-12 18:58:54 -07001079 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
Florin Corasb26743d2018-06-26 09:31:04 -07001080
Florin Coras42ceddb2018-12-12 10:56:01 -08001081 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
1082 {
Florin Coras47596832019-03-12 18:58:54 -07001083 if (seq_geq (tc->psh_seq, snd_nxt)
1084 && seq_lt (tc->psh_seq, snd_nxt + data_len))
Florin Coras42ceddb2018-12-12 10:56:01 -08001085 flags |= TCP_FLAG_PSH;
1086 }
Florin Coras47596832019-03-12 18:58:54 -07001087 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
Dave Barach68b0fb02017-02-28 15:15:56 -05001088 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1089 advertise_wnd);
Dave Barach68b0fb02017-02-28 15:15:56 -05001090
Florin Corasb26743d2018-06-26 09:31:04 -07001091 if (maybe_burst)
1092 {
Dave Barach178cf492018-11-13 16:34:13 -05001093 clib_memcpy_fast ((u8 *) (th + 1),
1094 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1095 tc->snd_opts_len);
Florin Corasb26743d2018-06-26 09:31:04 -07001096 }
1097 else
1098 {
1099 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1100 ASSERT (len == tc->snd_opts_len);
1101 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001102
Florin Coras93992a92017-05-24 18:03:56 -07001103 /*
1104 * Update connection variables
1105 */
1106
Florin Coras47596832019-03-12 18:58:54 -07001107 if (update_snd_nxt)
1108 tc->snd_nxt += data_len;
Florin Corasc28764f2017-04-26 00:08:42 -07001109 tc->rcv_las = tc->rcv_nxt;
Florin Coras3e350af2017-03-30 02:54:28 -07001110
Florin Corasedfe0ee2019-07-29 18:13:25 -07001111 tc->bytes_out += data_len;
1112 tc->data_segs_out += 1;
1113
Srikanth A02833ff2019-10-02 17:48:58 -07001114 th->checksum = tcp_compute_checksum (tc, b);
1115
Florin Corasa436a422019-08-20 07:09:31 -07001116 TCP_EVT (TCP_EVT_PKTIZE, tc);
Dave Barach68b0fb02017-02-28 15:15:56 -05001117}
1118
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001119always_inline u32
1120tcp_buffer_len (vlib_buffer_t * b)
1121{
1122 u32 data_len = b->current_length;
1123 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1124 data_len += b->total_length_not_including_first_buffer;
1125 return data_len;
1126}
1127
Florin Coras0dbd5172018-06-25 16:19:34 -07001128u32
Florin Coras14ed6df2019-03-06 21:13:42 -08001129tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
Florin Coras0dbd5172018-06-25 16:19:34 -07001130{
Florin Coras14ed6df2019-03-06 21:13:42 -08001131 tcp_connection_t *tc = (tcp_connection_t *) tconn;
Florin Coras52814732019-06-12 15:38:19 -07001132
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001133 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1134 tcp_bt_track_tx (tc, tcp_buffer_len (b));
Florin Coras52814732019-06-12 15:38:19 -07001135
Florin Coras47596832019-03-12 18:58:54 -07001136 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1137 /* update_snd_nxt */ 1);
Florin Coras52814732019-06-12 15:38:19 -07001138
Florin Coras47596832019-03-12 18:58:54 -07001139 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
Florin Coras0dbd5172018-06-25 16:19:34 -07001140 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1141 /* If not tracking an ACK, start tracking */
1142 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1143 {
Florin Corasd67f1122018-05-21 17:47:40 -07001144 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
Florin Coras0dbd5172018-06-25 16:19:34 -07001145 tc->rtt_seq = tc->snd_nxt;
1146 }
1147 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1148 {
1149 tcp_retransmit_timer_set (tc);
1150 tc->rto_boff = 0;
1151 }
1152 tcp_trajectory_add_start (b, 3);
1153 return 0;
1154}
1155
Dave Barach68b0fb02017-02-28 15:15:56 -05001156void
Florin Coras6792ec02017-03-13 03:49:51 -07001157tcp_send_ack (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001158{
Florin Corasbe72ae62018-11-01 11:23:03 -07001159 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1160 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -05001161 vlib_buffer_t *b;
1162 u32 bi;
1163
Florin Corasbdf7fd62019-01-31 17:31:01 -08001164 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras222e1f412019-02-16 20:47:32 -08001165 {
1166 tcp_update_rcv_wnd (tc);
1167 return;
1168 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001169 b = vlib_get_buffer (vm, bi);
Florin Coras24793e32018-05-09 11:34:25 -07001170 tcp_init_buffer (vm, b);
Dave Barach68b0fb02017-02-28 15:15:56 -05001171 tcp_make_ack (tc, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001172 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05001173}
1174
Florin Coras7ac053b2018-11-05 15:57:21 -08001175void
Florin Coras26dd6de2019-07-23 23:54:47 -07001176tcp_program_ack (tcp_connection_t * tc)
Florin Coras7ac053b2018-11-05 15:57:21 -08001177{
1178 if (!(tc->flags & TCP_CONN_SNDACK))
1179 {
Florin Coras26dd6de2019-07-23 23:54:47 -07001180 session_add_self_custom_tx_evt (&tc->connection, 1);
Florin Coras7ac053b2018-11-05 15:57:21 -08001181 tc->flags |= TCP_CONN_SNDACK;
1182 }
1183}
1184
1185void
Florin Coras26dd6de2019-07-23 23:54:47 -07001186tcp_program_dupack (tcp_connection_t * tc)
Florin Coras7ac053b2018-11-05 15:57:21 -08001187{
1188 if (!(tc->flags & TCP_CONN_SNDACK))
1189 {
Florin Coras26dd6de2019-07-23 23:54:47 -07001190 session_add_self_custom_tx_evt (&tc->connection, 1);
Florin Coras7ac053b2018-11-05 15:57:21 -08001191 tc->flags |= TCP_CONN_SNDACK;
1192 }
1193 if (tc->pending_dupacks < 255)
1194 tc->pending_dupacks += 1;
1195}
1196
1197void
Florin Coras36ebcff2019-09-12 18:36:44 -07001198tcp_program_retransmit (tcp_connection_t * tc)
Florin Coras7ac053b2018-11-05 15:57:21 -08001199{
Florin Coras36ebcff2019-09-12 18:36:44 -07001200 if (!(tc->flags & TCP_CONN_RXT_PENDING))
Florin Coras7ac053b2018-11-05 15:57:21 -08001201 {
Florin Coras26dd6de2019-07-23 23:54:47 -07001202 session_add_self_custom_tx_evt (&tc->connection, 0);
Florin Coras36ebcff2019-09-12 18:36:44 -07001203 tc->flags |= TCP_CONN_RXT_PENDING;
Florin Coras7ac053b2018-11-05 15:57:21 -08001204 }
Florin Coras7ac053b2018-11-05 15:57:21 -08001205}
1206
Florin Corasb2215d62017-08-01 16:56:58 -07001207/**
1208 * Delayed ack timer handler
1209 *
1210 * Sends delayed ACK when timer expires
1211 */
Florin Coras6792ec02017-03-13 03:49:51 -07001212void
Florin Corasb72a0ff2019-11-22 17:38:25 -08001213tcp_timer_delack_handler (u32 index, u32 thread_index)
Florin Coras6792ec02017-03-13 03:49:51 -07001214{
Florin Coras6792ec02017-03-13 03:49:51 -07001215 tcp_connection_t *tc;
1216
1217 tc = tcp_connection_get (index, thread_index);
Florin Coras6792ec02017-03-13 03:49:51 -07001218 tcp_send_ack (tc);
1219}
1220
Florin Corasb2215d62017-08-01 16:56:58 -07001221/**
Florin Coras017dc452019-08-30 11:06:35 -07001222 * Send window update ack
1223 *
1224 * Ensures that it will be sent only once, after a zero rwnd has been
1225 * advertised in a previous ack, and only if rwnd has grown beyond a
1226 * configurable value.
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001227 */
1228void
1229tcp_send_window_update_ack (tcp_connection_t * tc)
1230{
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001231 if (tcp_zero_rwnd_sent (tc))
1232 {
Florin Coras017dc452019-08-30 11:06:35 -07001233 tcp_update_rcv_wnd (tc);
1234 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001235 {
1236 tcp_zero_rwnd_sent_off (tc);
Florin Coras26dd6de2019-07-23 23:54:47 -07001237 tcp_program_ack (tc);
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001238 }
1239 }
1240}
1241
1242/**
Florin Coras36ee9f12018-11-02 12:52:10 -07001243 * Allocate a new buffer and build a new tcp segment
Dave Barach68b0fb02017-02-28 15:15:56 -05001244 *
Florin Coras36ee9f12018-11-02 12:52:10 -07001245 * @param wrk tcp worker
1246 * @param tc connection for which the segment will be allocated
1247 * @param offset offset of the first byte in the tx fifo
1248 * @param max_deq_byte segment size
1249 * @param[out] b pointer to buffer allocated
1250 *
1251 * @return the number of bytes in the segment or 0 if buffer cannot be
1252 * allocated or no data available
Florin Coras93992a92017-05-24 18:03:56 -07001253 */
Florin Coras36ee9f12018-11-02 12:52:10 -07001254static int
1255tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1256 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
Dave Barach68b0fb02017-02-28 15:15:56 -05001257{
Florin Corasbe72ae62018-11-01 11:23:03 -07001258 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1259 vlib_main_t *vm = wrk->vm;
Florin Corasbdf7fd62019-01-31 17:31:01 -08001260 u32 bi, seg_size;
Florin Coras93992a92017-05-24 18:03:56 -07001261 int n_bytes = 0;
Florin Corase87216f2017-08-17 16:59:22 -07001262 u8 *data;
Dave Barach68b0fb02017-02-28 15:15:56 -05001263
Florin Coras1ee78302019-02-05 15:51:15 -08001264 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
Florin Coras1f152cd2017-08-18 19:28:03 -07001265
Florin Corasb2215d62017-08-01 16:56:58 -07001266 /*
1267 * Prepare options
1268 */
Florin Corasc8343412017-05-04 14:25:50 -07001269 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1270
Florin Corasb2215d62017-08-01 16:56:58 -07001271 /*
1272 * Allocate and fill in buffer(s)
1273 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001274
Florin Corasb2215d62017-08-01 16:56:58 -07001275 /* Easy case, buffer size greater than mss */
Florin Corasbe72ae62018-11-01 11:23:03 -07001276 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
Florin Corasb2215d62017-08-01 16:56:58 -07001277 {
Florin Corasbdf7fd62019-01-31 17:31:01 -08001278 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras24793e32018-05-09 11:34:25 -07001279 return 0;
1280 *b = vlib_get_buffer (vm, bi);
1281 data = tcp_init_buffer (vm, *b);
Florin Coras31c99552019-03-01 13:00:58 -08001282 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1283 max_deq_bytes);
Florin Corasb2215d62017-08-01 16:56:58 -07001284 ASSERT (n_bytes == max_deq_bytes);
1285 b[0]->current_length = n_bytes;
Florin Coras47596832019-03-12 18:58:54 -07001286 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1287 /* burst */ 0, /* update_snd_nxt */ 0);
Florin Corasb2215d62017-08-01 16:56:58 -07001288 }
1289 /* Split mss into multiple buffers */
1290 else
1291 {
Florin Corasbdf7fd62019-01-31 17:31:01 -08001292 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1293 u16 n_peeked, len_to_deq;
Florin Corasb2215d62017-08-01 16:56:58 -07001294 vlib_buffer_t *chain_b, *prev_b;
Florin Corasb2215d62017-08-01 16:56:58 -07001295 int i;
1296
Florin Corasb2215d62017-08-01 16:56:58 -07001297 /* Make sure we have enough buffers */
Florin Corasbe72ae62018-11-01 11:23:03 -07001298 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001299 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1300 CLIB_CACHE_LINE_BYTES);
1301 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1302 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
Florin Corasb2215d62017-08-01 16:56:58 -07001303 {
Florin Corasbdf7fd62019-01-31 17:31:01 -08001304 if (n_bufs)
1305 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1306 return 0;
Florin Corasb2215d62017-08-01 16:56:58 -07001307 }
1308
Florin Corasbdf7fd62019-01-31 17:31:01 -08001309 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
Florin Coras24793e32018-05-09 11:34:25 -07001310 data = tcp_init_buffer (vm, *b);
Florin Coras31c99552019-03-01 13:00:58 -08001311 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1312 bytes_per_buffer -
1313 TRANSPORT_MAX_HDRS_LEN);
Florin Corasb2215d62017-08-01 16:56:58 -07001314 b[0]->current_length = n_bytes;
1315 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1316 b[0]->total_length_not_including_first_buffer = 0;
Florin Corasb2215d62017-08-01 16:56:58 -07001317 max_deq_bytes -= n_bytes;
1318
1319 chain_b = *b;
1320 for (i = 1; i < n_bufs_per_seg; i++)
1321 {
1322 prev_b = chain_b;
Florin Corasbe72ae62018-11-01 11:23:03 -07001323 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001324 chain_bi = wrk->tx_buffers[--n_bufs];
Florin Corasb2215d62017-08-01 16:56:58 -07001325 chain_b = vlib_get_buffer (vm, chain_bi);
1326 chain_b->current_data = 0;
Florin Corase87216f2017-08-17 16:59:22 -07001327 data = vlib_buffer_get_current (chain_b);
Florin Coras31c99552019-03-01 13:00:58 -08001328 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1329 offset + n_bytes,
1330 len_to_deq);
Florin Corasb2215d62017-08-01 16:56:58 -07001331 ASSERT (n_peeked == len_to_deq);
Florin Coras1f152cd2017-08-18 19:28:03 -07001332 n_bytes += n_peeked;
Florin Corasb2215d62017-08-01 16:56:58 -07001333 chain_b->current_length = n_peeked;
Florin Coras1f152cd2017-08-18 19:28:03 -07001334 chain_b->next_buffer = 0;
Florin Corasb2215d62017-08-01 16:56:58 -07001335
1336 /* update previous buffer */
1337 prev_b->next_buffer = chain_bi;
1338 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1339
Florin Corasb2215d62017-08-01 16:56:58 -07001340 max_deq_bytes -= n_peeked;
Florin Coras1f152cd2017-08-18 19:28:03 -07001341 b[0]->total_length_not_including_first_buffer += n_peeked;
Florin Corasb2215d62017-08-01 16:56:58 -07001342 }
Florin Coras1f152cd2017-08-18 19:28:03 -07001343
Florin Coras47596832019-03-12 18:58:54 -07001344 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1345 /* burst */ 0, /* update_snd_nxt */ 0);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001346
1347 if (PREDICT_FALSE (n_bufs))
1348 {
1349 clib_warning ("not all buffers consumed");
1350 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1351 }
Florin Corasb2215d62017-08-01 16:56:58 -07001352 }
1353
Florin Coras93992a92017-05-24 18:03:56 -07001354 ASSERT (n_bytes > 0);
Florin Corasbe72ae62018-11-01 11:23:03 -07001355 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
Florin Corasbb292f42017-05-19 09:49:19 -07001356
Florin Coras36ee9f12018-11-02 12:52:10 -07001357 return n_bytes;
1358}
1359
1360/**
1361 * Build a retransmit segment
1362 *
1363 * @return the number of bytes in the segment or 0 if there's nothing to
1364 * retransmit
1365 */
1366static u32
1367tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1368 tcp_connection_t * tc, u32 offset,
1369 u32 max_deq_bytes, vlib_buffer_t ** b)
1370{
1371 u32 start, available_bytes;
1372 int n_bytes = 0;
1373
1374 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1375 ASSERT (max_deq_bytes != 0);
1376
1377 /*
1378 * Make sure we can retransmit something
1379 */
Florin Coras31c99552019-03-01 13:00:58 -08001380 available_bytes = transport_max_tx_dequeue (&tc->connection);
Florin Coras36ee9f12018-11-02 12:52:10 -07001381 ASSERT (available_bytes >= offset);
1382 available_bytes -= offset;
1383 if (!available_bytes)
1384 return 0;
1385
1386 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1387 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1388
Florin Coras36ee9f12018-11-02 12:52:10 -07001389 start = tc->snd_una + offset;
Florin Coras81cb8e42019-10-22 19:44:45 -07001390 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1391
Florin Coras36ee9f12018-11-02 12:52:10 -07001392 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1393 if (!n_bytes)
1394 return 0;
1395
Florin Coras36ebcff2019-09-12 18:36:44 -07001396 tc->snd_rxt_bytes += n_bytes;
1397
Florin Corasbbcfaac2019-10-10 13:52:04 -07001398 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Coras36ebcff2019-09-12 18:36:44 -07001399 tcp_bt_track_rxt (tc, start, start + n_bytes);
Dave Barach68b0fb02017-02-28 15:15:56 -05001400
Florin Corasedfe0ee2019-07-29 18:13:25 -07001401 tc->bytes_retrans += n_bytes;
1402 tc->segs_retrans += 1;
Florin Corasa436a422019-08-20 07:09:31 -07001403 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
Florin Coras36ebcff2019-09-12 18:36:44 -07001404
Dave Barach68b0fb02017-02-28 15:15:56 -05001405 return n_bytes;
1406}
1407
Florin Coras36ebcff2019-09-12 18:36:44 -07001408static void
1409tcp_check_sack_reneging (tcp_connection_t * tc)
1410{
1411 sack_scoreboard_t *sb = &tc->sack_sb;
1412 sack_scoreboard_hole_t *hole;
1413
1414 hole = scoreboard_first_hole (sb);
1415 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1416 return;
1417
1418 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1419}
1420
Florin Coras6792ec02017-03-13 03:49:51 -07001421/**
1422 * Reset congestion control, switch cwnd to loss window and try again.
1423 */
1424static void
Florin Corasa3c32652019-07-03 17:47:22 -07001425tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
Florin Coras6792ec02017-03-13 03:49:51 -07001426{
Florin Corasa436a422019-08-20 07:09:31 -07001427 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
Florin Coras36ebcff2019-09-12 18:36:44 -07001428
Florin Coras93992a92017-05-24 18:03:56 -07001429 tc->prev_ssthresh = tc->ssthresh;
1430 tc->prev_cwnd = tc->cwnd;
1431
Florin Coras36ebcff2019-09-12 18:36:44 -07001432 /* If we entrered loss without fast recovery, notify cc algo of the
1433 * congestion event such that it can update ssthresh and its state */
1434 if (!tcp_in_fastrecovery (tc))
1435 tcp_cc_congestion (tc);
Florin Corasa3c32652019-07-03 17:47:22 -07001436
Florin Coras36ebcff2019-09-12 18:36:44 -07001437 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
Florin Corasa3c32652019-07-03 17:47:22 -07001438 tcp_cc_loss (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001439
Florin Corasf1762d62017-09-24 19:43:08 -04001440 tc->rtt_ts = 0;
Florin Corasd2aab832018-05-22 11:39:59 -07001441 tc->cwnd_acc_bytes = 0;
Florin Corasedfe0ee2019-07-29 18:13:25 -07001442 tc->tr_occurences += 1;
Florin Coras3af90fc2017-05-03 21:09:42 -07001443 tcp_recovery_on (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001444}
1445
Florin Coras75c48c12019-08-02 15:17:21 -07001446void
Florin Corasb72a0ff2019-11-22 17:38:25 -08001447tcp_timer_retransmit_handler (u32 tc_index, u32 thread_index)
Dave Barach68b0fb02017-02-28 15:15:56 -05001448{
Florin Corasbe72ae62018-11-01 11:23:03 -07001449 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1450 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -05001451 tcp_connection_t *tc;
Florin Corasb2215d62017-08-01 16:56:58 -07001452 vlib_buffer_t *b = 0;
Florin Coras3af90fc2017-05-03 21:09:42 -07001453 u32 bi, n_bytes;
Dave Barach68b0fb02017-02-28 15:15:56 -05001454
Florin Coras75c48c12019-08-02 15:17:21 -07001455 tc = tcp_connection_get (tc_index, thread_index);
1456
1457 /* Note: the connection may have been closed and pool_put */
1458 if (PREDICT_FALSE (tc == 0 || tc->state == TCP_STATE_SYN_SENT))
1459 return;
1460
Florin Coras75c48c12019-08-02 15:17:21 -07001461 /* Wait-close and retransmit could pop at the same time */
1462 if (tc->state == TCP_STATE_CLOSED)
1463 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001464
Florin Corase04c2992017-03-01 08:17:34 -08001465 if (tc->state >= TCP_STATE_ESTABLISHED)
Dave Barach68b0fb02017-02-28 15:15:56 -05001466 {
Florin Corasa436a422019-08-20 07:09:31 -07001467 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
Florin Corase55a6d72018-10-31 23:09:22 -07001468
Florin Coras93992a92017-05-24 18:03:56 -07001469 /* Lost FIN, retransmit and return */
Florin Coras222e1f412019-02-16 20:47:32 -08001470 if (tc->flags & TCP_CONN_FINSNT)
Florin Coras93992a92017-05-24 18:03:56 -07001471 {
1472 tcp_send_fin (tc);
Florin Corasf988e692017-11-27 04:34:14 -05001473 tc->rto_boff += 1;
1474 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
Florin Coras93992a92017-05-24 18:03:56 -07001475 return;
1476 }
1477
Florin Coras3ec66b02018-08-23 16:27:05 -07001478 /* Shouldn't be here. This condition is tricky because it has to take
1479 * into account boff > 0 due to persist timeout. */
Florin Coras47596832019-03-12 18:58:54 -07001480 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
Florin Coras3ec66b02018-08-23 16:27:05 -07001481 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1482 && !tcp_flight_size (tc)))
Florin Corasa096f2d2017-09-28 23:49:42 -04001483 {
Florin Coras3ec66b02018-08-23 16:27:05 -07001484 ASSERT (!tcp_in_recovery (tc));
1485 tc->rto_boff = 0;
Florin Corasa096f2d2017-09-28 23:49:42 -04001486 return;
1487 }
1488
Florin Coras3ec66b02018-08-23 16:27:05 -07001489 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1490 * to persist timer timeout */
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001491 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1492 {
1493 tc->rto_boff = 0;
1494 tcp_update_rto (tc);
1495 }
1496
Florin Coras548f7572019-06-07 15:31:06 -07001497 /* Peer is dead or network connectivity is lost. Close connection.
1498 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1499 * a min rto of 0.2s we need to retry about 8 times. */
1500 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1501 {
1502 tcp_send_reset (tc);
1503 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1504 session_transport_closing_notify (&tc->connection);
Florin Coras52be6742019-11-14 23:32:08 -08001505 session_transport_closed_notify (&tc->connection);
Florin Coras548f7572019-06-07 15:31:06 -07001506 tcp_connection_timers_reset (tc);
Florin Coras9094b5c2019-08-12 14:17:47 -07001507 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
Florin Coras548f7572019-06-07 15:31:06 -07001508 return;
1509 }
1510
Florin Coras36ebcff2019-09-12 18:36:44 -07001511 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1512 tcp_check_sack_reneging (tc);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001513
Florin Coras36ebcff2019-09-12 18:36:44 -07001514 /* Update send congestion to make sure that rxt has data to send */
1515 tc->snd_congestion = tc->snd_nxt;
Florin Corasa3c32652019-07-03 17:47:22 -07001516
Florin Coras36ebcff2019-09-12 18:36:44 -07001517 /* Send the first unacked segment. If we're short on buffers, return
1518 * as soon as possible */
Florin Coras81cb8e42019-10-22 19:44:45 -07001519 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1520 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
Florin Coras85a3ddd2018-12-24 16:54:34 -08001521 if (!n_bytes)
Florin Corase04c2992017-03-01 08:17:34 -08001522 {
Florin Coras222e1f412019-02-16 20:47:32 -08001523 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
Florin Corase04c2992017-03-01 08:17:34 -08001524 return;
1525 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001526
Dave Barachb7f1faa2017-08-29 11:43:37 -04001527 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001528 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras75c48c12019-08-02 15:17:21 -07001529
1530 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
Florin Coras3ec66b02018-08-23 16:27:05 -07001531 tcp_retransmit_timer_force_update (tc);
Florin Coras36ebcff2019-09-12 18:36:44 -07001532
1533 tc->rto_boff += 1;
1534 if (tc->rto_boff == 1)
1535 {
1536 tcp_cc_init_rxt_timeout (tc);
1537 /* Record timestamp. Eifel detection algorithm RFC3522 */
1538 tc->snd_rxt_ts = tcp_tstamp (tc);
1539 }
1540
1541 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Corasbe237bf2019-09-27 08:16:40 -07001542 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
Florin Coras36ebcff2019-09-12 18:36:44 -07001543
1544 tcp_program_retransmit (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001545 }
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001546 /* Retransmit SYN-ACK */
1547 else if (tc->state == TCP_STATE_SYN_RCVD)
1548 {
Florin Corasa436a422019-08-20 07:09:31 -07001549 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
Florin Corase55a6d72018-10-31 23:09:22 -07001550
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001551 tc->rtt_ts = 0;
1552
Florin Coras75c48c12019-08-02 15:17:21 -07001553 /* Passive open establish timeout */
1554 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1555 {
1556 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1557 tcp_connection_timers_reset (tc);
Florin Coras9094b5c2019-08-12 14:17:47 -07001558 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
Florin Coras75c48c12019-08-02 15:17:21 -07001559 return;
1560 }
Florin Coras222e1f412019-02-16 20:47:32 -08001561
Florin Corasbdf7fd62019-01-31 17:31:01 -08001562 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Corasf988e692017-11-27 04:34:14 -05001563 {
Florin Coras222e1f412019-02-16 20:47:32 -08001564 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
Florin Corasf988e692017-11-27 04:34:14 -05001565 return;
1566 }
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001567
Florin Coras75c48c12019-08-02 15:17:21 -07001568 tc->rto_boff += 1;
1569 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1570 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1571
1572 tcp_retransmit_timer_force_update (tc);
1573
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001574 b = vlib_get_buffer (vm, bi);
Florin Coras24793e32018-05-09 11:34:25 -07001575 tcp_init_buffer (vm, b);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001576 tcp_make_synack (tc, b);
Florin Corasa436a422019-08-20 07:09:31 -07001577 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001578
1579 /* Retransmit timer already updated, just enqueue to output */
Florin Corasbe72ae62018-11-01 11:23:03 -07001580 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05001581 }
Florin Coras93992a92017-05-24 18:03:56 -07001582 else
1583 {
1584 ASSERT (tc->state == TCP_STATE_CLOSED);
Florin Coras93992a92017-05-24 18:03:56 -07001585 return;
1586 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001587}
1588
Florin Coras75c48c12019-08-02 15:17:21 -07001589/**
1590 * SYN retransmit timer handler. Active open only.
1591 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001592void
Florin Corasb72a0ff2019-11-22 17:38:25 -08001593tcp_timer_retransmit_syn_handler (u32 tc_index, u32 thread_index)
Dave Barach68b0fb02017-02-28 15:15:56 -05001594{
Florin Coras75c48c12019-08-02 15:17:21 -07001595 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1596 vlib_main_t *vm = wrk->vm;
1597 tcp_connection_t *tc;
1598 vlib_buffer_t *b = 0;
1599 u32 bi;
Dave Barach68b0fb02017-02-28 15:15:56 -05001600
Florin Coras75c48c12019-08-02 15:17:21 -07001601 tc = tcp_half_open_connection_get (tc_index);
1602
1603 /* Note: the connection may have transitioned to ESTABLISHED... */
1604 if (PREDICT_FALSE (tc == 0 || tc->state != TCP_STATE_SYN_SENT))
1605 return;
1606
Florin Coras75c48c12019-08-02 15:17:21 -07001607 /* Half-open connection actually moved to established but we were
1608 * waiting for syn retransmit to pop to call cleanup from the right
1609 * thread. */
1610 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1611 {
1612 if (tcp_half_open_connection_cleanup (tc))
1613 TCP_DBG ("could not remove half-open connection");
1614 return;
1615 }
1616
Florin Corasa436a422019-08-20 07:09:31 -07001617 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
Florin Coras75c48c12019-08-02 15:17:21 -07001618 tc->rtt_ts = 0;
1619
1620 /* Active open establish timeout */
1621 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1622 {
1623 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
1624 tcp_connection_cleanup (tc);
1625 return;
1626 }
1627
1628 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1629 {
1630 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1631 return;
1632 }
1633
1634 /* Try without increasing RTO a number of times. If this fails,
1635 * start growing RTO exponentially */
1636 tc->rto_boff += 1;
1637 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1638 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1639
1640 b = vlib_get_buffer (vm, bi);
1641 tcp_init_buffer (vm, b);
1642 tcp_make_syn (tc, b);
1643
Florin Corasa436a422019-08-20 07:09:31 -07001644 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
Florin Coras75c48c12019-08-02 15:17:21 -07001645
1646 /* This goes straight to ipx_lookup */
1647 tcp_push_ip_hdr (wrk, tc, b);
1648 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1649
1650 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1651 tc->rto * TCP_TO_TIMER_TICK);
Dave Barach68b0fb02017-02-28 15:15:56 -05001652}
1653
1654/**
Florin Coras3e350af2017-03-30 02:54:28 -07001655 * Got 0 snd_wnd from peer, try to do something about it.
1656 *
1657 */
1658void
Florin Corasb72a0ff2019-11-22 17:38:25 -08001659tcp_timer_persist_handler (u32 index, u32 thread_index)
Florin Coras3e350af2017-03-30 02:54:28 -07001660{
Florin Corasbe72ae62018-11-01 11:23:03 -07001661 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1662 u32 bi, max_snd_bytes, available_bytes, offset;
1663 tcp_main_t *tm = vnet_get_tcp_main ();
1664 vlib_main_t *vm = wrk->vm;
Florin Coras3e350af2017-03-30 02:54:28 -07001665 tcp_connection_t *tc;
1666 vlib_buffer_t *b;
Florin Coras93992a92017-05-24 18:03:56 -07001667 int n_bytes = 0;
Florin Coras1f152cd2017-08-18 19:28:03 -07001668 u8 *data;
Florin Coras3e350af2017-03-30 02:54:28 -07001669
Florin Corasdb84e572017-05-09 18:54:52 -07001670 tc = tcp_connection_get_if_valid (index, thread_index);
Florin Corasdb84e572017-05-09 18:54:52 -07001671 if (!tc)
1672 return;
Florin Coras3e350af2017-03-30 02:54:28 -07001673
Florin Coras3e350af2017-03-30 02:54:28 -07001674 /* Problem already solved or worse */
Florin Coras7e74bf32019-03-06 16:51:58 -08001675 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1676 || (tc->flags & TCP_CONN_FINSNT))
Florin Coras3e350af2017-03-30 02:54:28 -07001677 return;
1678
Florin Coras31c99552019-03-01 13:00:58 -08001679 available_bytes = transport_max_tx_dequeue (&tc->connection);
Florin Coras47596832019-03-12 18:58:54 -07001680 offset = tc->snd_nxt - tc->snd_una;
Florin Coras50958952017-08-29 14:50:13 -07001681
1682 /* Reprogram persist if no new bytes available to send. We may have data
1683 * next time */
1684 if (!available_bytes)
1685 {
1686 tcp_persist_timer_set (tc);
1687 return;
1688 }
1689
1690 if (available_bytes <= offset)
1691 {
1692 ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
1693 return;
1694 }
1695
Florin Coras3e350af2017-03-30 02:54:28 -07001696 /* Increment RTO backoff */
1697 tc->rto_boff += 1;
1698 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1699
Florin Corasb2215d62017-08-01 16:56:58 -07001700 /*
1701 * Try to force the first unsent segment (or buffer)
1702 */
Florin Corasbdf7fd62019-01-31 17:31:01 -08001703 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras3ec66b02018-08-23 16:27:05 -07001704 {
1705 tcp_persist_timer_set (tc);
1706 return;
1707 }
Florin Coras3e350af2017-03-30 02:54:28 -07001708 b = vlib_get_buffer (vm, bi);
Florin Coras1f152cd2017-08-18 19:28:03 -07001709 data = tcp_init_buffer (vm, b);
Florin Coras93992a92017-05-24 18:03:56 -07001710
Florin Coras1f152cd2017-08-18 19:28:03 -07001711 tcp_validate_txf_size (tc, offset);
Florin Corasc8343412017-05-04 14:25:50 -07001712 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
Florin Coras7e74bf32019-03-06 16:51:58 -08001713 max_snd_bytes = clib_min (tc->snd_mss,
1714 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1715 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1716 max_snd_bytes);
Florin Coras3e350af2017-03-30 02:54:28 -07001717 b->current_length = n_bytes;
Florin Coras84275e92017-09-26 12:30:40 -04001718 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1719 || tc->snd_nxt == tc->snd_una_max
1720 || tc->rto_boff > 1));
Florin Coras93992a92017-05-24 18:03:56 -07001721
Florin Corasbbcfaac2019-10-10 13:52:04 -07001722 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Corasdd60b1b2019-10-07 17:19:09 -07001723 {
1724 tcp_bt_check_app_limited (tc);
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001725 tcp_bt_track_tx (tc, n_bytes);
Florin Corasdd60b1b2019-10-07 17:19:09 -07001726 }
1727
Florin Coras47596832019-03-12 18:58:54 -07001728 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1729 /* burst */ 0, /* update_snd_nxt */ 1);
1730 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
Florin Coras8b20bf52018-06-14 14:55:50 -07001731 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
Florin Corasbe72ae62018-11-01 11:23:03 -07001732 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras3e350af2017-03-30 02:54:28 -07001733
Florin Coras1f152cd2017-08-18 19:28:03 -07001734 /* Just sent new data, enable retransmit */
1735 tcp_retransmit_timer_update (tc);
Florin Coras3e350af2017-03-30 02:54:28 -07001736}
1737
1738/**
Florin Coras6792ec02017-03-13 03:49:51 -07001739 * Retransmit first unacked segment
1740 */
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001741int
Florin Corasbe72ae62018-11-01 11:23:03 -07001742tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001743{
Florin Corasbe72ae62018-11-01 11:23:03 -07001744 vlib_main_t *vm = wrk->vm;
1745 vlib_buffer_t *b;
Florin Coras47596832019-03-12 18:58:54 -07001746 u32 bi, n_bytes;
Dave Barach68b0fb02017-02-28 15:15:56 -05001747
Florin Corasa436a422019-08-20 07:09:31 -07001748 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001749
Florin Corasbe72ae62018-11-01 11:23:03 -07001750 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
Florin Corasb2215d62017-08-01 16:56:58 -07001751 if (!n_bytes)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001752 return -1;
1753
Florin Corasb2215d62017-08-01 16:56:58 -07001754 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001755 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001756
1757 return 0;
Florin Coras6792ec02017-03-13 03:49:51 -07001758}
1759
Florin Coras36ee9f12018-11-02 12:52:10 -07001760static int
Florin Coras36ebcff2019-09-12 18:36:44 -07001761tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1762 u32 burst_size)
Florin Coras36ee9f12018-11-02 12:52:10 -07001763{
Florin Coras635acbf2019-07-31 14:11:05 -07001764 u32 offset, n_segs = 0, n_written, bi, available_wnd;
Florin Coras36ee9f12018-11-02 12:52:10 -07001765 vlib_main_t *vm = wrk->vm;
1766 vlib_buffer_t *b = 0;
1767
Florin Coras47596832019-03-12 18:58:54 -07001768 offset = tc->snd_nxt - tc->snd_una;
Florin Coras635acbf2019-07-31 14:11:05 -07001769 available_wnd = tc->snd_wnd - offset;
1770 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1771
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001772 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1773 tcp_bt_check_app_limited (tc);
1774
Florin Coras36ee9f12018-11-02 12:52:10 -07001775 while (n_segs < burst_size)
1776 {
1777 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1778 if (!n_written)
1779 goto done;
1780
1781 bi = vlib_get_buffer_index (vm, b);
1782 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1783 offset += n_written;
1784 n_segs += 1;
Florin Coras47596832019-03-12 18:58:54 -07001785
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001786 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1787 tcp_bt_track_tx (tc, n_written);
1788
Florin Coras47596832019-03-12 18:58:54 -07001789 tc->snd_nxt += n_written;
1790 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
Florin Coras36ee9f12018-11-02 12:52:10 -07001791 }
1792
1793done:
1794 return n_segs;
1795}
1796
Florin Coras36ebcff2019-09-12 18:36:44 -07001797/**
1798 * Estimate send space using proportional rate reduction (RFC6937)
1799 */
Florin Corasbe237bf2019-09-27 08:16:40 -07001800int
Florin Coras36ebcff2019-09-12 18:36:44 -07001801tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1802{
1803 u32 pipe, prr_out;
1804 int space;
1805
1806 pipe = tcp_flight_size (tc);
1807 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1808
1809 if (pipe > tc->ssthresh)
1810 {
1811 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1812 - prr_out;
1813 }
1814 else
1815 {
Florin Corasbe237bf2019-09-27 08:16:40 -07001816 int limit;
1817 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
Florin Coras36ebcff2019-09-12 18:36:44 -07001818 space = clib_min (tc->ssthresh - pipe, limit);
1819 }
1820 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1821 return space;
1822}
1823
Florin Corasbe237bf2019-09-27 08:16:40 -07001824static inline u8
1825tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1826 sack_scoreboard_t * sb)
1827{
1828 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1829 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1830
Florin Corasb3dce892019-10-30 09:22:14 -07001831 if (tcp_fastrecovery_first (tc))
1832 return 1;
1833
Florin Corasbe237bf2019-09-27 08:16:40 -07001834 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1835}
1836
Florin Corascb711a42019-10-16 19:28:17 -07001837static inline u8
1838tcp_max_tx_deq (tcp_connection_t * tc)
1839{
1840 return (transport_max_tx_dequeue (&tc->connection)
1841 - (tc->snd_nxt - tc->snd_una));
1842}
1843
Florin Coras36ee9f12018-11-02 12:52:10 -07001844#define scoreboard_rescue_rxt_valid(_sb, _tc) \
1845 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1846 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1847
Florin Coras6792ec02017-03-13 03:49:51 -07001848/**
Florin Coras36ebcff2019-09-12 18:36:44 -07001849 * Do retransmit with SACKs
Florin Coras6792ec02017-03-13 03:49:51 -07001850 */
Florin Coras36ebcff2019-09-12 18:36:44 -07001851static int
1852tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1853 u32 burst_size)
Dave Barach68b0fb02017-02-28 15:15:56 -05001854{
Florin Coras36ebcff2019-09-12 18:36:44 -07001855 u32 n_written = 0, offset, max_bytes, n_segs = 0;
Florin Coras11e9e352019-11-13 19:09:47 -08001856 u8 snd_limited = 0, can_rescue = 0;
1857 u32 bi, max_deq, burst_bytes;
Florin Coras93992a92017-05-24 18:03:56 -07001858 sack_scoreboard_hole_t *hole;
Florin Coras36ee9f12018-11-02 12:52:10 -07001859 vlib_main_t *vm = wrk->vm;
1860 vlib_buffer_t *b = 0;
Florin Coras93992a92017-05-24 18:03:56 -07001861 sack_scoreboard_t *sb;
Florin Coras93992a92017-05-24 18:03:56 -07001862 int snd_space;
Dave Barach68b0fb02017-02-28 15:15:56 -05001863
Florin Coras36ebcff2019-09-12 18:36:44 -07001864 ASSERT (tcp_in_cong_recovery (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -05001865
Florin Corasa8e71c82019-10-22 19:01:39 -07001866 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
Florin Corasc31dc312019-10-06 14:06:14 -07001867 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1868 if (!burst_size)
1869 {
1870 tcp_program_retransmit (tc);
1871 return 0;
1872 }
1873
Florin Coras36ebcff2019-09-12 18:36:44 -07001874 if (tcp_in_recovery (tc))
1875 snd_space = tcp_available_cc_snd_space (tc);
1876 else
1877 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1878
Florin Corasca1c8f32018-05-23 21:01:30 -07001879 if (snd_space < tc->snd_mss)
Florin Coras11e9e352019-11-13 19:09:47 -08001880 goto done;
Florin Corasc31dc312019-10-06 14:06:14 -07001881
Florin Coras36ee9f12018-11-02 12:52:10 -07001882 sb = &tc->sack_sb;
Florin Corasbe237bf2019-09-27 08:16:40 -07001883
1884 /* Check if snd_una is a lost retransmit */
Florin Coras8a8b05c2019-10-16 10:07:39 -07001885 if (pool_elts (sb->holes)
1886 && seq_gt (sb->high_sacked, tc->snd_congestion)
Florin Corasbe237bf2019-09-27 08:16:40 -07001887 && tc->rxt_head != tc->snd_una
1888 && tcp_retransmit_should_retry_head (tc, sb))
1889 {
Florin Corasbf1f8b72019-11-04 14:39:33 -08001890 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1891 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
Florin Corasbe237bf2019-09-27 08:16:40 -07001892 if (!n_written)
1893 {
1894 tcp_program_retransmit (tc);
1895 goto done;
1896 }
1897 bi = vlib_get_buffer_index (vm, b);
1898 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1899 n_segs = 1;
1900
1901 tc->rxt_head = tc->snd_una;
1902 tc->rxt_delivered += n_written;
1903 tc->prr_delivered += n_written;
1904 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1905 }
1906
Florin Corasb3dce892019-10-30 09:22:14 -07001907 tcp_fastrecovery_first_off (tc);
1908
Florin Corasbe237bf2019-09-27 08:16:40 -07001909 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
Florin Coras36ee9f12018-11-02 12:52:10 -07001910 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1911
Florin Coras31c99552019-03-01 13:00:58 -08001912 max_deq = transport_max_tx_dequeue (&tc->connection);
Florin Coras47596832019-03-12 18:58:54 -07001913 max_deq -= tc->snd_nxt - tc->snd_una;
Florin Coras36ee9f12018-11-02 12:52:10 -07001914
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001915 while (snd_space > 0 && n_segs < burst_size)
Florin Coras93992a92017-05-24 18:03:56 -07001916 {
Florin Coras81cb8e42019-10-22 19:44:45 -07001917 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
Florin Coras36ee9f12018-11-02 12:52:10 -07001918 &snd_limited);
Florin Coras93992a92017-05-24 18:03:56 -07001919 if (!hole)
1920 {
Florin Coras36ebcff2019-09-12 18:36:44 -07001921 /* We are out of lost holes to retransmit so send some new data. */
Florin Corasbe237bf2019-09-27 08:16:40 -07001922 if (max_deq > tc->snd_mss)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001923 {
Florin Corasc31dc312019-10-06 14:06:14 -07001924 u32 n_segs_new;
1925 int av_wnd;
1926
Florin Coras3eba7f12019-11-15 17:56:48 -08001927 /* Make sure we don't exceed available window and leave space
1928 * for one more packet, to avoid zero window acks */
Florin Corasc31dc312019-10-06 14:06:14 -07001929 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
Florin Coras3eba7f12019-11-15 17:56:48 -08001930 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
Florin Corasc31dc312019-10-06 14:06:14 -07001931 snd_space = clib_min (snd_space, av_wnd);
Florin Coras36ee9f12018-11-02 12:52:10 -07001932 snd_space = clib_min (max_deq, snd_space);
1933 burst_size = clib_min (burst_size - n_segs,
1934 snd_space / tc->snd_mss);
Florin Coras36ebcff2019-09-12 18:36:44 -07001935 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1936 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1937 if (max_deq > n_segs_new * tc->snd_mss)
1938 tcp_program_retransmit (tc);
1939
1940 n_segs += n_segs_new;
Florin Coras36ee9f12018-11-02 12:52:10 -07001941 goto done;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001942 }
Florin Coras93992a92017-05-24 18:03:56 -07001943
Florin Coras36ebcff2019-09-12 18:36:44 -07001944 if (tcp_in_recovery (tc) || !can_rescue
1945 || scoreboard_rescue_rxt_valid (sb, tc))
Florin Coras36ee9f12018-11-02 12:52:10 -07001946 break;
1947
Florin Coras93992a92017-05-24 18:03:56 -07001948 /* If rescue rxt undefined or less than snd_una then one segment of
1949 * up to SMSS octets that MUST include the highest outstanding
1950 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1951 * RecoveryPoint. HighRxt MUST NOT be updated.
1952 */
Florin Coras3eba7f12019-11-15 17:56:48 -08001953 hole = scoreboard_last_hole (sb);
1954 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
Florin Coras1f152cd2017-08-18 19:28:03 -07001955 max_bytes = clib_min (max_bytes, snd_space);
Florin Coras3eba7f12019-11-15 17:56:48 -08001956 offset = hole->end - tc->snd_una - max_bytes;
Florin Corasbe72ae62018-11-01 11:23:03 -07001957 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1958 max_bytes, &b);
Florin Coras24793e32018-05-09 11:34:25 -07001959 if (!n_written)
1960 goto done;
1961
Florin Coras3eba7f12019-11-15 17:56:48 -08001962 sb->rescue_rxt = tc->snd_congestion;
Florin Corasb2215d62017-08-01 16:56:58 -07001963 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001964 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001965 n_segs += 1;
Florin Coras93992a92017-05-24 18:03:56 -07001966 break;
1967 }
1968
Florin Coras1f152cd2017-08-18 19:28:03 -07001969 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1970 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1971 if (max_bytes == 0)
1972 break;
Florin Coras36ee9f12018-11-02 12:52:10 -07001973
Florin Coras93992a92017-05-24 18:03:56 -07001974 offset = sb->high_rxt - tc->snd_una;
Florin Corasbe72ae62018-11-01 11:23:03 -07001975 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1976 &b);
Florin Coras36ee9f12018-11-02 12:52:10 -07001977 ASSERT (n_written <= snd_space);
Florin Coras93992a92017-05-24 18:03:56 -07001978
1979 /* Nothing left to retransmit */
1980 if (n_written == 0)
Florin Corasb2215d62017-08-01 16:56:58 -07001981 break;
Florin Coras93992a92017-05-24 18:03:56 -07001982
Florin Corasb2215d62017-08-01 16:56:58 -07001983 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001984 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras36ee9f12018-11-02 12:52:10 -07001985
1986 sb->high_rxt += n_written;
Florin Coras81cb8e42019-10-22 19:44:45 -07001987 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1988
Florin Coras93992a92017-05-24 18:03:56 -07001989 snd_space -= n_written;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001990 n_segs += 1;
Florin Coras93992a92017-05-24 18:03:56 -07001991 }
1992
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001993 if (hole)
Florin Coras36ebcff2019-09-12 18:36:44 -07001994 tcp_program_retransmit (tc);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001995
Florin Coras24793e32018-05-09 11:34:25 -07001996done:
Florin Coras36ebcff2019-09-12 18:36:44 -07001997
Florin Coras11e9e352019-11-13 19:09:47 -08001998 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001999 return n_segs;
Florin Coras93992a92017-05-24 18:03:56 -07002000}
2001
2002/**
2003 * Fast retransmit without SACK info
2004 */
Florin Coras36ebcff2019-09-12 18:36:44 -07002005static int
2006tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
2007 u32 burst_size)
Florin Coras93992a92017-05-24 18:03:56 -07002008{
Florin Corasbf1f8b72019-11-04 14:39:33 -08002009 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
Florin Corasc31dc312019-10-06 14:06:14 -07002010 u32 burst_bytes, sent_bytes;
Florin Corasbe72ae62018-11-01 11:23:03 -07002011 vlib_main_t *vm = wrk->vm;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07002012 int snd_space, n_segs = 0;
Florin Corasc31dc312019-10-06 14:06:14 -07002013 u8 cc_limited = 0;
Florin Coras93992a92017-05-24 18:03:56 -07002014 vlib_buffer_t *b;
2015
Florin Corasbf1f8b72019-11-04 14:39:33 -08002016 ASSERT (tcp_in_cong_recovery (tc));
Florin Corasa436a422019-08-20 07:09:31 -07002017 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
Florin Coras6792ec02017-03-13 03:49:51 -07002018
Florin Corasa8e71c82019-10-22 19:01:39 -07002019 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
Florin Corasc31dc312019-10-06 14:06:14 -07002020 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
2021 if (!burst_size)
2022 {
2023 tcp_program_retransmit (tc);
2024 return 0;
2025 }
2026
Florin Coras87a9bf82019-06-12 11:26:35 -07002027 snd_space = tcp_available_cc_snd_space (tc);
Florin Corasc31dc312019-10-06 14:06:14 -07002028 cc_limited = snd_space < burst_bytes;
Florin Coras87a9bf82019-06-12 11:26:35 -07002029
Florin Coras36ee9f12018-11-02 12:52:10 -07002030 if (!tcp_fastrecovery_first (tc))
2031 goto send_unsent;
2032
2033 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
2034 * segment. */
Florin Corasbf4d5ce2018-10-19 16:26:24 -07002035 while (snd_space > 0 && n_segs < burst_size)
Dave Barach68b0fb02017-02-28 15:15:56 -05002036 {
Florin Corasbf1f8b72019-11-04 14:39:33 -08002037 max_bytes = clib_min (tc->snd_mss,
2038 tc->snd_congestion - tc->snd_una - offset);
2039 if (!max_bytes)
2040 break;
2041 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
2042 &b);
Dave Barach68b0fb02017-02-28 15:15:56 -05002043
2044 /* Nothing left to retransmit */
Florin Coras6792ec02017-03-13 03:49:51 -07002045 if (n_written == 0)
Florin Corasb2215d62017-08-01 16:56:58 -07002046 break;
Dave Barach68b0fb02017-02-28 15:15:56 -05002047
Florin Corasb2215d62017-08-01 16:56:58 -07002048 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07002049 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras6792ec02017-03-13 03:49:51 -07002050 snd_space -= n_written;
Florin Coras36ee9f12018-11-02 12:52:10 -07002051 offset += n_written;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07002052 n_segs += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05002053 }
2054
Florin Coras36ee9f12018-11-02 12:52:10 -07002055 if (n_segs == burst_size)
2056 goto done;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07002057
Florin Coras36ee9f12018-11-02 12:52:10 -07002058send_unsent:
2059
2060 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
Florin Coras9ece3c02018-11-05 11:06:53 -08002061 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
Florin Coras36ee9f12018-11-02 12:52:10 -07002062 goto done;
2063
Florin Coras31c99552019-03-01 13:00:58 -08002064 max_deq = transport_max_tx_dequeue (&tc->connection);
Florin Coras47596832019-03-12 18:58:54 -07002065 max_deq -= tc->snd_nxt - tc->snd_una;
Florin Coras36ee9f12018-11-02 12:52:10 -07002066 if (max_deq)
2067 {
2068 snd_space = clib_min (max_deq, snd_space);
2069 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
Florin Coras36ebcff2019-09-12 18:36:44 -07002070 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
Florin Corasbf1f8b72019-11-04 14:39:33 -08002071 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
Florin Coras36ebcff2019-09-12 18:36:44 -07002072 tcp_program_retransmit (tc);
Florin Coras36ee9f12018-11-02 12:52:10 -07002073 n_segs += n_segs_now;
2074 }
2075
Florin Coras36ee9f12018-11-02 12:52:10 -07002076done:
2077 tcp_fastrecovery_first_off (tc);
Florin Coras93992a92017-05-24 18:03:56 -07002078
Florin Corasc31dc312019-10-06 14:06:14 -07002079 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2080 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
2081 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
2082
2083 return n_segs;
Dave Barach68b0fb02017-02-28 15:15:56 -05002084}
Florin Coras26dd6de2019-07-23 23:54:47 -07002085
2086static int
2087tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
2088{
2089 int j, n_acks;
2090
2091 if (!tc->pending_dupacks)
2092 {
Florin Corascb711a42019-10-16 19:28:17 -07002093 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
2094 || tc->state != TCP_STATE_ESTABLISHED)
2095 {
2096 tcp_send_ack (tc);
2097 return 1;
2098 }
2099 return 0;
Florin Coras26dd6de2019-07-23 23:54:47 -07002100 }
2101
2102 /* If we're supposed to send dupacks but have no ooo data
2103 * send only one ack */
2104 if (!vec_len (tc->snd_sacks))
2105 {
2106 tcp_send_ack (tc);
Florin Corascb711a42019-10-16 19:28:17 -07002107 tc->pending_dupacks = 0;
Florin Coras26dd6de2019-07-23 23:54:47 -07002108 return 1;
2109 }
2110
2111 /* Start with first sack block */
2112 tc->snd_sack_pos = 0;
2113
2114 /* Generate enough dupacks to cover all sack blocks. Do not generate
2115 * more sacks than the number of packets received. But do generate at
2116 * least 3, i.e., the number needed to signal congestion, if needed. */
2117 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
2118 n_acks = clib_min (n_acks, tc->pending_dupacks);
2119 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
2120 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
2121 tcp_send_ack (tc);
2122
2123 if (n_acks < max_burst_size)
2124 {
2125 tc->pending_dupacks = 0;
2126 tc->snd_sack_pos = 0;
Florin Corasedfe0ee2019-07-29 18:13:25 -07002127 tc->dupacks_out += n_acks;
Florin Coras26dd6de2019-07-23 23:54:47 -07002128 return n_acks;
2129 }
2130 else
2131 {
2132 TCP_DBG ("constrained by burst size");
2133 tc->pending_dupacks = n_acks - max_burst_size;
Florin Corasedfe0ee2019-07-29 18:13:25 -07002134 tc->dupacks_out += max_burst_size;
Florin Coras26dd6de2019-07-23 23:54:47 -07002135 tcp_program_dupack (tc);
2136 return max_burst_size;
2137 }
2138}
2139
2140static int
Florin Coras36ebcff2019-09-12 18:36:44 -07002141tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
Florin Coras26dd6de2019-07-23 23:54:47 -07002142{
Florin Coras26dd6de2019-07-23 23:54:47 -07002143 tcp_worker_ctx_t *wrk;
Florin Corasc31dc312019-10-06 14:06:14 -07002144 u32 n_segs;
Florin Coras26dd6de2019-07-23 23:54:47 -07002145
Florin Corasfd4c3fe2019-11-07 12:33:12 -08002146 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2147 return 0;
2148
Florin Coras26dd6de2019-07-23 23:54:47 -07002149 wrk = tcp_get_worker (tc->c_thread_index);
Florin Coras26dd6de2019-07-23 23:54:47 -07002150
Florin Corasc31dc312019-10-06 14:06:14 -07002151 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2152 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2153 else
2154 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2155
Florin Coras26dd6de2019-07-23 23:54:47 -07002156 return n_segs;
2157}
2158
2159int
2160tcp_session_custom_tx (void *conn, u32 max_burst_size)
2161{
2162 tcp_connection_t *tc = (tcp_connection_t *) conn;
2163 u32 n_segs = 0;
2164
Florin Coras36ebcff2019-09-12 18:36:44 -07002165 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
Florin Coras26dd6de2019-07-23 23:54:47 -07002166 {
Florin Coras36ebcff2019-09-12 18:36:44 -07002167 tc->flags &= ~TCP_CONN_RXT_PENDING;
2168 n_segs = tcp_do_retransmit (tc, max_burst_size);
Florin Coras26dd6de2019-07-23 23:54:47 -07002169 max_burst_size -= n_segs;
2170 }
2171
2172 if (!(tc->flags & TCP_CONN_SNDACK))
2173 return n_segs;
2174
2175 tc->flags &= ~TCP_CONN_SNDACK;
2176
2177 /* We have retransmitted packets and no dupack */
2178 if (n_segs && !tc->pending_dupacks)
2179 return n_segs;
2180
2181 if (!max_burst_size)
2182 {
2183 tcp_program_ack (tc);
2184 return max_burst_size;
2185 }
2186
2187 n_segs += tcp_send_acks (tc, max_burst_size);
2188
2189 return n_segs;
2190}
Filip Tehlare275bed2019-03-06 00:06:56 -08002191#endif /* CLIB_MARCH_VARIANT */
Dave Barach68b0fb02017-02-28 15:15:56 -05002192
Florin Corasf9d05682018-04-26 08:26:52 -07002193static void
2194tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
Florin Coras8b20bf52018-06-14 14:55:50 -07002195 u16 * next0, u32 * error0)
Florin Corasf9d05682018-04-26 08:26:52 -07002196{
2197 ip_adjacency_t *adj;
2198 adj_index_t ai;
2199
Florin Coras1c8ff632018-05-17 13:28:34 -07002200 /* Not thread safe but as long as the connection exists the adj should
2201 * not be removed */
Florin Corasf9d05682018-04-26 08:26:52 -07002202 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2203 tc0->sw_if_index);
2204 if (ai == ADJ_INDEX_INVALID)
2205 {
Florin Corasf9d05682018-04-26 08:26:52 -07002206 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2207 *next0 = TCP_OUTPUT_NEXT_DROP;
2208 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2209 return;
2210 }
2211
2212 adj = adj_get (ai);
Florin Coras1c8ff632018-05-17 13:28:34 -07002213 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
Florin Corasf9d05682018-04-26 08:26:52 -07002214 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2215 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2216 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
Florin Coras1c8ff632018-05-17 13:28:34 -07002217 else
2218 {
2219 *next0 = TCP_OUTPUT_NEXT_DROP;
2220 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2221 }
2222 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
Florin Corasf9d05682018-04-26 08:26:52 -07002223}
2224
Florin Coras8b20bf52018-06-14 14:55:50 -07002225static void
2226tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2227 u32 * to_next, u32 n_bufs)
Dave Barach68b0fb02017-02-28 15:15:56 -05002228{
Florin Coras8b20bf52018-06-14 14:55:50 -07002229 u32 n_trace = vlib_get_trace_count (vm, node);
2230 tcp_connection_t *tc;
2231 tcp_tx_trace_t *t;
2232 vlib_buffer_t *b;
2233 tcp_header_t *th;
2234 int i;
Dave Barach68b0fb02017-02-28 15:15:56 -05002235
Florin Coras8b20bf52018-06-14 14:55:50 -07002236 for (i = 0; i < clib_min (n_trace, n_bufs); i++)
Dave Barach68b0fb02017-02-28 15:15:56 -05002237 {
Florin Coras8b20bf52018-06-14 14:55:50 -07002238 b = vlib_get_buffer (vm, to_next[i]);
2239 th = vlib_buffer_get_current (b);
2240 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2241 vm->thread_index);
2242 t = vlib_add_trace (vm, node, b, sizeof (*t));
Dave Barach178cf492018-11-13 16:34:13 -05002243 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2244 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
Florin Coras8b20bf52018-06-14 14:55:50 -07002245 }
2246}
Dave Barach68b0fb02017-02-28 15:15:56 -05002247
Florin Coras0dbd5172018-06-25 16:19:34 -07002248always_inline void
Florin Coras8b20bf52018-06-14 14:55:50 -07002249tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2250 tcp_connection_t * tc0, u8 is_ip4)
2251{
Florin Corasf4ce6ba2019-11-20 18:34:58 -08002252 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2253 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2254 b0->current_length);
Srikanth A02833ff2019-10-02 17:48:58 -07002255
Florin Coras8b20bf52018-06-14 14:55:50 -07002256 if (is_ip4)
Florin Corasf4ce6ba2019-11-20 18:34:58 -08002257 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2258 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
Florin Coras8b20bf52018-06-14 14:55:50 -07002259 else
Florin Corasf4ce6ba2019-11-20 18:34:58 -08002260 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2261 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
Florin Coras8b20bf52018-06-14 14:55:50 -07002262}
Dave Barach68b0fb02017-02-28 15:15:56 -05002263
Florin Coras0dbd5172018-06-25 16:19:34 -07002264always_inline void
Simon Zhang1146ff42019-09-02 22:54:00 +08002265tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2266{
Florin Corasbbcfaac2019-10-10 13:52:04 -07002267 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
Simon Zhang1146ff42019-09-02 22:54:00 +08002268 return;
Florin Corasbbcfaac2019-10-10 13:52:04 -07002269
Simon Zhang8a047ed2019-09-24 21:16:56 +08002270 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
Simon Zhang1146ff42019-09-02 22:54:00 +08002271
Simon Zhang8a047ed2019-09-24 21:16:56 +08002272 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2273 data_len += b->total_length_not_including_first_buffer;
2274
2275 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2276 return;
2277 else
Simon Zhang1146ff42019-09-02 22:54:00 +08002278 {
2279 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2280 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2281 b->flags |= VNET_BUFFER_F_GSO;
2282 vnet_buffer2 (b)->gso_l4_hdr_sz =
2283 sizeof (tcp_header_t) + tc->snd_opts_len;
2284 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2285 }
2286}
2287
2288always_inline void
Florin Coras8b20bf52018-06-14 14:55:50 -07002289tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
Florin Corasdf36f492019-08-18 18:09:28 -07002290 vlib_node_runtime_t * error_node, u16 * next0,
2291 u8 is_ip4)
Florin Coras8b20bf52018-06-14 14:55:50 -07002292{
Florin Coras540a8da2019-06-18 08:55:14 -07002293 /* If next_index is not drop use it */
Florin Coras07beade2019-06-20 12:18:31 -07002294 if (tc0->next_node_index)
2295 {
2296 *next0 = tc0->next_node_index;
2297 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2298 }
Florin Coras78dae002019-08-30 10:00:30 -07002299 else
2300 {
2301 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2302 }
Florin Coras540a8da2019-06-18 08:55:14 -07002303
Florin Coras8b20bf52018-06-14 14:55:50 -07002304 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2305 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2306
2307 if (!is_ip4)
2308 {
Florin Corasdf36f492019-08-18 18:09:28 -07002309 u32 error0 = 0;
2310
Florin Coras8b20bf52018-06-14 14:55:50 -07002311 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
Florin Corasdf36f492019-08-18 18:09:28 -07002312 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2313
2314 if (PREDICT_FALSE (error0))
2315 {
2316 b0->error = error_node->errors[error0];
2317 return;
2318 }
Florin Coras8b20bf52018-06-14 14:55:50 -07002319 }
2320
Florin Coras8b20bf52018-06-14 14:55:50 -07002321 if (!TCP_ALWAYS_ACK)
2322 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
Florin Corasedfe0ee2019-07-29 18:13:25 -07002323
2324 tc0->segs_out += 1;
Florin Coras8b20bf52018-06-14 14:55:50 -07002325}
2326
2327always_inline uword
2328tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2329 vlib_frame_t * frame, int is_ip4)
2330{
2331 u32 n_left_from, *from, thread_index = vm->thread_index;
2332 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2333 u16 nexts[VLIB_FRAME_SIZE], *next;
Florin Corasdf36f492019-08-18 18:09:28 -07002334 vlib_node_runtime_t *error_node;
2335
2336 error_node = vlib_node_get_runtime (vm, tcp_node_index (output, is_ip4));
Florin Coras8b20bf52018-06-14 14:55:50 -07002337
2338 from = vlib_frame_vector_args (frame);
2339 n_left_from = frame->n_vectors;
Florin Corasbe72ae62018-11-01 11:23:03 -07002340 tcp_set_time_now (tcp_get_worker (thread_index));
Florin Coras8b20bf52018-06-14 14:55:50 -07002341
2342 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2343 tcp46_output_trace_frame (vm, node, from, n_left_from);
2344
2345 vlib_get_buffers (vm, from, bufs, n_left_from);
2346 b = bufs;
2347 next = nexts;
2348
2349 while (n_left_from >= 4)
2350 {
Florin Coras8b20bf52018-06-14 14:55:50 -07002351 tcp_connection_t *tc0, *tc1;
2352
2353 {
2354 vlib_prefetch_buffer_header (b[2], STORE);
2355 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2356
2357 vlib_prefetch_buffer_header (b[3], STORE);
2358 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2359 }
2360
Florin Coras8b20bf52018-06-14 14:55:50 -07002361 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2362 thread_index);
2363 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2364 thread_index);
2365
Florin Coras78dae002019-08-30 10:00:30 -07002366 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2367 {
2368 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2369 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
Florin Coras8b20bf52018-06-14 14:55:50 -07002370
Simon Zhang1146ff42019-09-02 22:54:00 +08002371 tcp_check_if_gso (tc0, b[0]);
2372 tcp_check_if_gso (tc1, b[1]);
2373
Florin Coras78dae002019-08-30 10:00:30 -07002374 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2375 tcp_output_handle_packet (tc1, b[1], error_node, &next[1], is_ip4);
2376 }
2377 else
2378 {
2379 if (tc0 != 0)
2380 {
2381 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002382 tcp_check_if_gso (tc0, b[0]);
Florin Coras78dae002019-08-30 10:00:30 -07002383 tcp_output_handle_packet (tc0, b[0], error_node, &next[0],
2384 is_ip4);
2385 }
2386 else
2387 {
2388 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2389 next[0] = TCP_OUTPUT_NEXT_DROP;
2390 }
2391 if (tc1 != 0)
2392 {
2393 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002394 tcp_check_if_gso (tc1, b[1]);
Florin Coras78dae002019-08-30 10:00:30 -07002395 tcp_output_handle_packet (tc1, b[1], error_node, &next[1],
2396 is_ip4);
2397 }
2398 else
2399 {
2400 b[1]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2401 next[1] = TCP_OUTPUT_NEXT_DROP;
2402 }
2403 }
Florin Coras8b20bf52018-06-14 14:55:50 -07002404
2405 b += 2;
2406 next += 2;
2407 n_left_from -= 2;
2408 }
2409 while (n_left_from > 0)
2410 {
Florin Coras8b20bf52018-06-14 14:55:50 -07002411 tcp_connection_t *tc0;
2412
2413 if (n_left_from > 1)
2414 {
Florin Coras91ca4622018-06-30 11:27:59 -07002415 vlib_prefetch_buffer_header (b[1], STORE);
2416 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
Florin Coras8b20bf52018-06-14 14:55:50 -07002417 }
2418
Florin Coras8b20bf52018-06-14 14:55:50 -07002419 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2420 thread_index);
2421
Florin Coras78dae002019-08-30 10:00:30 -07002422 if (PREDICT_TRUE (tc0 != 0))
2423 {
2424 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002425 tcp_check_if_gso (tc0, b[0]);
Florin Coras78dae002019-08-30 10:00:30 -07002426 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2427 }
2428 else
2429 {
2430 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2431 next[0] = TCP_OUTPUT_NEXT_DROP;
2432 }
Florin Coras8b20bf52018-06-14 14:55:50 -07002433
2434 b += 1;
2435 next += 1;
2436 n_left_from -= 1;
2437 }
2438
2439 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
Florin Corasdf36f492019-08-18 18:09:28 -07002440 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2441 TCP_ERROR_PKTS_SENT, frame->n_vectors);
Florin Coras8b20bf52018-06-14 14:55:50 -07002442 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002443}
2444
Filip Tehlare275bed2019-03-06 00:06:56 -08002445VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2446 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002447{
2448 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2449}
2450
Filip Tehlare275bed2019-03-06 00:06:56 -08002451VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2452 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002453{
2454 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2455}
2456
Florin Corase69f4952017-03-07 10:06:24 -08002457/* *INDENT-OFF* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002458VLIB_REGISTER_NODE (tcp4_output_node) =
2459{
Dave Barachf970d2f2018-11-26 18:34:33 -05002460 .name = "tcp4-output",
2461 /* Takes a vector of packets. */
2462 .vector_size = sizeof (u32),
2463 .n_errors = TCP_N_ERROR,
Dave Barach7fff3d22018-11-27 16:52:59 -05002464 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
Dave Barachf970d2f2018-11-26 18:34:33 -05002465 .error_strings = tcp_error_strings,
2466 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2467 .next_nodes = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002468#define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2469 foreach_tcp4_output_next
2470#undef _
Dave Barachf970d2f2018-11-26 18:34:33 -05002471 },
2472 .format_buffer = format_tcp_header,
2473 .format_trace = format_tcp_tx_trace,
Florin Corase69f4952017-03-07 10:06:24 -08002474};
2475/* *INDENT-ON* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002476
Florin Corase69f4952017-03-07 10:06:24 -08002477/* *INDENT-OFF* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002478VLIB_REGISTER_NODE (tcp6_output_node) =
2479{
Florin Corase69f4952017-03-07 10:06:24 -08002480 .name = "tcp6-output",
Dave Barach68b0fb02017-02-28 15:15:56 -05002481 /* Takes a vector of packets. */
Florin Corase69f4952017-03-07 10:06:24 -08002482 .vector_size = sizeof (u32),
2483 .n_errors = TCP_N_ERROR,
Dave Barach7fff3d22018-11-27 16:52:59 -05002484 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
Florin Corase69f4952017-03-07 10:06:24 -08002485 .error_strings = tcp_error_strings,
2486 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2487 .next_nodes = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002488#define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2489 foreach_tcp6_output_next
2490#undef _
Florin Corase69f4952017-03-07 10:06:24 -08002491 },
2492 .format_buffer = format_tcp_header,
2493 .format_trace = format_tcp_tx_trace,
2494};
2495/* *INDENT-ON* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002496
Dave Barach68b0fb02017-02-28 15:15:56 -05002497typedef enum _tcp_reset_next
2498{
2499 TCP_RESET_NEXT_DROP,
2500 TCP_RESET_NEXT_IP_LOOKUP,
2501 TCP_RESET_N_NEXT
2502} tcp_reset_next_t;
2503
2504#define foreach_tcp4_reset_next \
2505 _(DROP, "error-drop") \
2506 _(IP_LOOKUP, "ip4-lookup")
2507
2508#define foreach_tcp6_reset_next \
2509 _(DROP, "error-drop") \
2510 _(IP_LOOKUP, "ip6-lookup")
2511
2512static uword
2513tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2514 vlib_frame_t * from_frame, u8 is_ip4)
2515{
2516 u32 n_left_from, next_index, *from, *to_next;
Damjan Marion586afd72017-04-05 19:18:20 +02002517 u32 my_thread_index = vm->thread_index;
Dave Barach68b0fb02017-02-28 15:15:56 -05002518
2519 from = vlib_frame_vector_args (from_frame);
2520 n_left_from = from_frame->n_vectors;
2521
2522 next_index = node->cached_next_index;
2523
2524 while (n_left_from > 0)
2525 {
2526 u32 n_left_to_next;
2527
2528 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2529
2530 while (n_left_from > 0 && n_left_to_next > 0)
2531 {
2532 u32 bi0;
2533 vlib_buffer_t *b0;
Clement Durand6cf260c2017-04-13 13:27:04 +02002534 tcp_tx_trace_t *t0;
2535 tcp_header_t *th0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002536 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2537
2538 bi0 = from[0];
2539 to_next[0] = bi0;
2540 from += 1;
2541 to_next += 1;
2542 n_left_from -= 1;
2543 n_left_to_next -= 1;
2544
2545 b0 = vlib_get_buffer (vm, bi0);
2546
2547 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2548 my_thread_index, is_ip4))
2549 {
2550 error0 = TCP_ERROR_LOOKUP_DROPS;
2551 next0 = TCP_RESET_NEXT_DROP;
2552 goto done;
2553 }
2554
2555 /* Prepare to send to IP lookup */
Florin Corasf988e692017-11-27 04:34:14 -05002556 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002557 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2558
2559 done:
Florin Corase69f4952017-03-07 10:06:24 -08002560 b0->error = node->errors[error0];
Damjan Marion213b5aa2017-07-13 21:19:27 +02002561 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
Dave Barach68b0fb02017-02-28 15:15:56 -05002562 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2563 {
Clement Durand6cf260c2017-04-13 13:27:04 +02002564 th0 = vlib_buffer_get_current (b0);
2565 if (is_ip4)
2566 th0 = ip4_next_header ((ip4_header_t *) th0);
2567 else
2568 th0 = ip6_next_header ((ip6_header_t *) th0);
Clement Durand6cf260c2017-04-13 13:27:04 +02002569 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
Dave Barach178cf492018-11-13 16:34:13 -05002570 clib_memcpy_fast (&t0->tcp_header, th0,
2571 sizeof (t0->tcp_header));
Dave Barach68b0fb02017-02-28 15:15:56 -05002572 }
2573
2574 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2575 n_left_to_next, bi0, next0);
2576 }
2577 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2578 }
2579 return from_frame->n_vectors;
2580}
2581
Filip Tehlare275bed2019-03-06 00:06:56 -08002582VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2583 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002584{
2585 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2586}
2587
Filip Tehlare275bed2019-03-06 00:06:56 -08002588VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2589 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002590{
2591 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2592}
2593
2594/* *INDENT-OFF* */
2595VLIB_REGISTER_NODE (tcp4_reset_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002596 .name = "tcp4-reset",
2597 .vector_size = sizeof (u32),
2598 .n_errors = TCP_N_ERROR,
2599 .error_strings = tcp_error_strings,
2600 .n_next_nodes = TCP_RESET_N_NEXT,
2601 .next_nodes = {
2602#define _(s,n) [TCP_RESET_NEXT_##s] = n,
2603 foreach_tcp4_reset_next
2604#undef _
2605 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002606 .format_trace = format_tcp_tx_trace,
Dave Barach68b0fb02017-02-28 15:15:56 -05002607};
2608/* *INDENT-ON* */
2609
2610/* *INDENT-OFF* */
2611VLIB_REGISTER_NODE (tcp6_reset_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002612 .name = "tcp6-reset",
2613 .vector_size = sizeof (u32),
2614 .n_errors = TCP_N_ERROR,
2615 .error_strings = tcp_error_strings,
2616 .n_next_nodes = TCP_RESET_N_NEXT,
2617 .next_nodes = {
2618#define _(s,n) [TCP_RESET_NEXT_##s] = n,
2619 foreach_tcp6_reset_next
2620#undef _
2621 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002622 .format_trace = format_tcp_tx_trace,
Dave Barach68b0fb02017-02-28 15:15:56 -05002623};
2624/* *INDENT-ON* */
2625
Dave Barach68b0fb02017-02-28 15:15:56 -05002626/*
2627 * fd.io coding-style-patch-verification: ON
2628 *
2629 * Local Variables:
2630 * eval: (c-set-style "gnu")
2631 * End:
2632 */