blob: 88ae0a32b60555d8293da87b4ffe9fed3f6b1d7b [file] [log] [blame]
Dave Barach68b0fb02017-02-28 15:15:56 -05001/*
Florin Coras830fe732019-02-15 18:20:58 -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 <vppinfra/sparse_vec.h>
Simon Zhang1146ff42019-09-02 22:54:00 +080017#include <vnet/fib/ip4_fib.h>
18#include <vnet/fib/ip6_fib.h>
Dave Barach68b0fb02017-02-28 15:15:56 -050019#include <vnet/tcp/tcp.h>
Florin Coras999840c2020-03-18 20:31:34 +000020#include <vnet/tcp/tcp_inlines.h>
Dave Barach68b0fb02017-02-28 15:15:56 -050021#include <vnet/session/session.h>
22#include <math.h>
23
Filip Tehlar0c4931c2021-10-06 09:47:41 +000024static vlib_error_desc_t tcp_input_error_counters[] = {
25#define tcp_error(f, n, s, d) { #n, d, VL_COUNTER_SEVERITY_##s },
Dave Barach68b0fb02017-02-28 15:15:56 -050026#include <vnet/tcp/tcp_error.def>
27#undef tcp_error
28};
29
Filip Tehlarbc4dc162023-04-17 12:22:12 +020030typedef enum _tcp_input_next
31{
32 TCP_INPUT_NEXT_DROP,
33 TCP_INPUT_NEXT_LISTEN,
34 TCP_INPUT_NEXT_RCV_PROCESS,
35 TCP_INPUT_NEXT_SYN_SENT,
36 TCP_INPUT_NEXT_ESTABLISHED,
37 TCP_INPUT_NEXT_RESET,
38 TCP_INPUT_NEXT_PUNT,
39 TCP_INPUT_N_NEXT
40} tcp_input_next_t;
41
Dave Barach68b0fb02017-02-28 15:15:56 -050042/**
43 * Validate segment sequence number. As per RFC793:
44 *
45 * Segment Receive Test
46 * Length Window
47 * ------- ------- -------------------------------------------
48 * 0 0 SEG.SEQ = RCV.NXT
49 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
50 * >0 0 not acceptable
51 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
52 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
53 *
54 * This ultimately consists in checking if segment falls within the window.
55 * The one important difference compared to RFC793 is that we use rcv_las,
56 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
57 * peer's reference when computing our receive window.
58 *
Florin Coras6792ec02017-03-13 03:49:51 -070059 * This:
60 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
61 * however, is too strict when we have retransmits. Instead we just check that
62 * the seq is not beyond the right edge and that the end of the segment is not
63 * less than the left edge.
64 *
65 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
66 * use rcv_nxt in the right edge window test instead of rcv_las.
67 *
Dave Barach68b0fb02017-02-28 15:15:56 -050068 */
69always_inline u8
70tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
71{
Florin Coras6792ec02017-03-13 03:49:51 -070072 return (seq_geq (end_seq, tc->rcv_las)
73 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
Dave Barach68b0fb02017-02-28 15:15:56 -050074}
75
Florin Corasdb84e572017-05-09 18:54:52 -070076/**
Florin Corasc28764f2017-04-26 00:08:42 -070077 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
78 * timestamp to echo and it's less than tsval_recent, drop segment
79 * but still send an ACK in order to retain TCP's mechanism for detecting
80 * and recovering from half-open connections
81 *
82 * Or at least that's what the theory says. It seems that this might not work
83 * very well with packet reordering and fast retransmit. XXX
84 */
Dave Barach68b0fb02017-02-28 15:15:56 -050085always_inline int
86tcp_segment_check_paws (tcp_connection_t * tc)
87{
Florin Corasea41aac2018-12-06 17:24:59 -080088 return tcp_opts_tstamp (&tc->rcv_opts)
Florin Coras93992a92017-05-24 18:03:56 -070089 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
Dave Barach68b0fb02017-02-28 15:15:56 -050090}
91
92/**
Florin Corasc28764f2017-04-26 00:08:42 -070093 * Update tsval recent
94 */
95always_inline void
96tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
97{
98 /*
99 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
100 * of an incoming segment:
101 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
102 * then the TSval from the segment is copied to TS.Recent;
103 * otherwise, the TSval is ignored.
104 */
Florin Corasf1762d62017-09-24 19:43:08 -0400105 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
106 && seq_leq (tc->rcv_las, seq_end))
Florin Corasc28764f2017-04-26 00:08:42 -0700107 {
Dave Barach2c25a622017-06-26 11:35:07 -0400108 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
Florin Coras93992a92017-05-24 18:03:56 -0700109 tc->tsval_recent = tc->rcv_opts.tsval;
Florin Coras8f10b902021-04-02 18:32:00 -0700110 tc->tsval_recent_age = tcp_time_tstamp (tc->c_thread_index);
Florin Corasc28764f2017-04-26 00:08:42 -0700111 }
112}
113
Florin Coras6939d5e2020-02-10 23:22:34 +0000114static void
115tcp_handle_rst (tcp_connection_t * tc)
116{
117 switch (tc->rst_state)
118 {
119 case TCP_STATE_SYN_RCVD:
120 /* Cleanup everything. App wasn't notified yet */
121 session_transport_delete_notify (&tc->connection);
122 tcp_connection_cleanup (tc);
123 break;
124 case TCP_STATE_SYN_SENT:
Florin Coras67fe7782020-09-02 10:51:10 -0700125 session_stream_connect_notify (&tc->connection, SESSION_E_REFUSED);
Florin Coras6939d5e2020-02-10 23:22:34 +0000126 tcp_connection_cleanup (tc);
127 break;
128 case TCP_STATE_ESTABLISHED:
129 session_transport_reset_notify (&tc->connection);
130 session_transport_closed_notify (&tc->connection);
131 break;
132 case TCP_STATE_CLOSE_WAIT:
133 case TCP_STATE_FIN_WAIT_1:
134 case TCP_STATE_FIN_WAIT_2:
135 case TCP_STATE_CLOSING:
136 case TCP_STATE_LAST_ACK:
137 session_transport_closed_notify (&tc->connection);
138 break;
139 case TCP_STATE_CLOSED:
140 case TCP_STATE_TIME_WAIT:
141 break;
142 default:
143 TCP_DBG ("reset state: %u", tc->state);
144 }
145}
146
147static void
148tcp_program_reset_ntf (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
149{
150 if (!tcp_disconnect_pending (tc))
151 {
152 tc->rst_state = tc->state;
153 vec_add1 (wrk->pending_resets, tc->c_c_index);
154 tcp_disconnect_pending_on (tc);
155 }
156}
157
158/**
159 * Handle reset packet
160 *
161 * Programs disconnect/reset notification that should be sent
162 * later by calling @ref tcp_handle_disconnects
163 */
164static void
165tcp_rcv_rst (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
166{
167 TCP_EVT (TCP_EVT_RST_RCVD, tc);
168 switch (tc->state)
169 {
170 case TCP_STATE_SYN_RCVD:
171 tcp_program_reset_ntf (wrk, tc);
172 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
173 break;
174 case TCP_STATE_SYN_SENT:
Florin Coras96acc9b2020-02-18 22:51:26 +0000175 /* Do not program ntf because the connection is half-open */
Ivan Shvedunove52eafd2020-07-29 19:15:41 +0300176 tc->rst_state = tc->state;
Florin Coras96acc9b2020-02-18 22:51:26 +0000177 tcp_handle_rst (tc);
Florin Coras6939d5e2020-02-10 23:22:34 +0000178 break;
179 case TCP_STATE_ESTABLISHED:
180 tcp_connection_timers_reset (tc);
Florin Coras6939d5e2020-02-10 23:22:34 +0000181 tcp_cong_recovery_off (tc);
182 tcp_program_reset_ntf (wrk, tc);
183 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
Florin Coras7a3a8662020-02-22 02:27:21 +0000184 tcp_program_cleanup (wrk, tc);
Florin Coras6939d5e2020-02-10 23:22:34 +0000185 break;
186 case TCP_STATE_CLOSE_WAIT:
187 case TCP_STATE_FIN_WAIT_1:
188 case TCP_STATE_FIN_WAIT_2:
189 case TCP_STATE_CLOSING:
190 case TCP_STATE_LAST_ACK:
191 tcp_connection_timers_reset (tc);
Florin Coras6939d5e2020-02-10 23:22:34 +0000192 tcp_cong_recovery_off (tc);
193 tcp_program_reset_ntf (wrk, tc);
194 /* Make sure we mark the session as closed. In some states we may
195 * be still trying to send data */
196 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
Florin Coras7a3a8662020-02-22 02:27:21 +0000197 tcp_program_cleanup (wrk, tc);
Florin Coras6939d5e2020-02-10 23:22:34 +0000198 break;
199 case TCP_STATE_CLOSED:
200 case TCP_STATE_TIME_WAIT:
201 break;
202 default:
203 TCP_DBG ("reset state: %u", tc->state);
204 }
205}
206
Florin Corasc28764f2017-04-26 00:08:42 -0700207/**
Dave Barach68b0fb02017-02-28 15:15:56 -0500208 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
209 *
210 * It first verifies if segment has a wrapped sequence number (PAWS) and then
211 * does the processing associated to the first four steps (ignoring security
212 * and precedence): sequence number, rst bit and syn bit checks.
213 *
214 * @return 0 if segments passes validation.
215 */
216static int
Florin Coras7ac053b2018-11-05 15:57:21 -0800217tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
218 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
Dave Barach68b0fb02017-02-28 15:15:56 -0500219{
Florin Corasca1c8f32018-05-23 21:01:30 -0700220 /* We could get a burst of RSTs interleaved with acks */
221 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
222 {
223 tcp_send_reset (tc0);
224 *error0 = TCP_ERROR_CONNECTION_CLOSED;
Florin Coras7ac053b2018-11-05 15:57:21 -0800225 goto error;
Florin Corasca1c8f32018-05-23 21:01:30 -0700226 }
227
Dave Barach68b0fb02017-02-28 15:15:56 -0500228 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
Florin Coras00cd22d2018-04-18 13:20:18 -0700229 {
230 *error0 = TCP_ERROR_SEGMENT_INVALID;
Florin Coras7ac053b2018-11-05 15:57:21 -0800231 goto error;
Florin Coras00cd22d2018-04-18 13:20:18 -0700232 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500233
Florin Coras80231112018-12-05 15:59:31 -0800234 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
Florin Corasdb84e572017-05-09 18:54:52 -0700235 {
Florin Coras00cd22d2018-04-18 13:20:18 -0700236 *error0 = TCP_ERROR_OPTIONS;
Florin Coras7ac053b2018-11-05 15:57:21 -0800237 goto error;
Florin Corasdb84e572017-05-09 18:54:52 -0700238 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500239
Florin Coras00cd22d2018-04-18 13:20:18 -0700240 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500241 {
Florin Coras00cd22d2018-04-18 13:20:18 -0700242 *error0 = TCP_ERROR_PAWS;
Florin Corasa436a422019-08-20 07:09:31 -0700243 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
244 vnet_buffer (b0)->tcp.seq_end);
Dave Barach68b0fb02017-02-28 15:15:56 -0500245
246 /* If it just so happens that a segment updates tsval_recent for a
247 * segment over 24 days old, invalidate tsval_recent. */
248 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
Florin Coras8f10b902021-04-02 18:32:00 -0700249 tcp_time_tstamp (tc0->c_thread_index)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500250 {
Florin Corasea41aac2018-12-06 17:24:59 -0800251 tc0->tsval_recent = tc0->rcv_opts.tsval;
Florin Coras91236ce2018-12-16 11:41:45 -0800252 clib_warning ("paws failed: 24-day old segment");
Dave Barach68b0fb02017-02-28 15:15:56 -0500253 }
Florin Coras91236ce2018-12-16 11:41:45 -0800254 /* Drop after ack if not rst. Resets can fail paws check as per
255 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
256 * be subjected to the PAWS check by verifying an acceptable value in
257 * SEG.TSval */
258 else if (!tcp_rst (th0))
Dave Barach68b0fb02017-02-28 15:15:56 -0500259 {
Florin Coras26dd6de2019-07-23 23:54:47 -0700260 tcp_program_ack (tc0);
Florin Corasa436a422019-08-20 07:09:31 -0700261 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
Florin Coras91236ce2018-12-16 11:41:45 -0800262 goto error;
Dave Barach68b0fb02017-02-28 15:15:56 -0500263 }
264 }
265
266 /* 1st: check sequence number */
267 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
268 vnet_buffer (b0)->tcp.seq_end))
269 {
Florin Coras830fe732019-02-15 18:20:58 -0800270 /* SYN/SYN-ACK retransmit */
271 if (tcp_syn (th0)
272 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
273 {
274 tcp_options_parse (th0, &tc0->rcv_opts, 1);
275 if (tc0->state == TCP_STATE_SYN_RCVD)
276 {
277 tcp_send_synack (tc0);
Florin Corasa436a422019-08-20 07:09:31 -0700278 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
Florin Coras830fe732019-02-15 18:20:58 -0800279 *error0 = TCP_ERROR_SYNS_RCVD;
280 }
281 else
282 {
Florin Coras26dd6de2019-07-23 23:54:47 -0700283 tcp_program_ack (tc0);
Florin Corasa436a422019-08-20 07:09:31 -0700284 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
Florin Coras830fe732019-02-15 18:20:58 -0800285 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
286 }
287 goto error;
288 }
289
Florin Coras6792ec02017-03-13 03:49:51 -0700290 /* If our window is 0 and the packet is in sequence, let it pass
Florin Coras00cd22d2018-04-18 13:20:18 -0700291 * through for ack processing. It should be dropped later. */
Florin Coras7e74bf32019-03-06 16:51:58 -0800292 if (tc0->rcv_wnd < tc0->snd_mss
Florin Coras222e1f412019-02-16 20:47:32 -0800293 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
294 goto check_reset;
295
296 /* If we entered recovery and peer did so as well, there's a chance that
297 * dup acks won't be acceptable on either end because seq_end may be less
298 * than rcv_las. This can happen if acks are lost in both directions. */
299 if (tcp_in_recovery (tc0)
300 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
301 tc0->rcv_las - tc0->rcv_wnd)
302 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
303 tc0->rcv_nxt + tc0->rcv_wnd))
304 goto check_reset;
305
306 *error0 = TCP_ERROR_RCV_WND;
307
Florin Corasa495a3e2019-08-29 18:33:24 -0700308 /* If we advertised a zero rcv_wnd and the segment is in the past or the
309 * next one that we expect, it is probably a window probe */
310 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
311 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
312 tc0->rcv_las + tc0->rcv_opts.mss))
313 *error0 = TCP_ERROR_ZERO_RWND;
314
Florin Corasedfe0ee2019-07-29 18:13:25 -0700315 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
316 tc0->rcv_las);
317
Florin Coras222e1f412019-02-16 20:47:32 -0800318 /* If not RST, send dup ack */
319 if (!tcp_rst (th0))
Florin Coras6792ec02017-03-13 03:49:51 -0700320 {
Florin Coras26dd6de2019-07-23 23:54:47 -0700321 tcp_program_dupack (tc0);
Florin Corasa436a422019-08-20 07:09:31 -0700322 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
Florin Coras6792ec02017-03-13 03:49:51 -0700323 }
Florin Coras222e1f412019-02-16 20:47:32 -0800324 goto error;
325
326 check_reset:
327 ;
Dave Barach68b0fb02017-02-28 15:15:56 -0500328 }
329
330 /* 2nd: check the RST bit */
Florin Coras00cd22d2018-04-18 13:20:18 -0700331 if (PREDICT_FALSE (tcp_rst (th0)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500332 {
Florin Coras6939d5e2020-02-10 23:22:34 +0000333 tcp_rcv_rst (wrk, tc0);
Florin Coras00cd22d2018-04-18 13:20:18 -0700334 *error0 = TCP_ERROR_RST_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -0800335 goto error;
Dave Barach68b0fb02017-02-28 15:15:56 -0500336 }
337
338 /* 3rd: check security and precedence (skip) */
339
Florin Coras830fe732019-02-15 18:20:58 -0800340 /* 4th: check the SYN bit (in window) */
Florin Coras00cd22d2018-04-18 13:20:18 -0700341 if (PREDICT_FALSE (tcp_syn (th0)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500342 {
Florin Corasd567a8d2019-06-07 12:38:55 -0700343 /* As per RFC5961 send challenge ack instead of reset */
Florin Coras26dd6de2019-07-23 23:54:47 -0700344 tcp_program_ack (tc0);
Florin Coras830fe732019-02-15 18:20:58 -0800345 *error0 = TCP_ERROR_SPURIOUS_SYN;
Florin Coras00cd22d2018-04-18 13:20:18 -0700346 goto error;
Dave Barach68b0fb02017-02-28 15:15:56 -0500347 }
348
Florin Corasc28764f2017-04-26 00:08:42 -0700349 /* If segment in window, save timestamp */
350 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
351 vnet_buffer (b0)->tcp.seq_end);
Dave Barach68b0fb02017-02-28 15:15:56 -0500352 return 0;
Florin Coras00cd22d2018-04-18 13:20:18 -0700353
Florin Coras00cd22d2018-04-18 13:20:18 -0700354error:
Florin Coras00cd22d2018-04-18 13:20:18 -0700355 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500356}
357
358always_inline int
Florin Corasf65074e2019-03-31 17:17:11 -0700359tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
Dave Barach68b0fb02017-02-28 15:15:56 -0500360{
361 /* SND.UNA =< SEG.ACK =< SND.NXT */
Florin Corasf65074e2019-03-31 17:17:11 -0700362 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
363 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
364 {
Florin Corasf65074e2019-03-31 17:17:11 -0700365 *error = TCP_ERROR_ACK_INVALID;
366 return -1;
367 }
368
Florin Corasf65074e2019-03-31 17:17:11 -0700369 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
370 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
371 *error = TCP_ERROR_ACK_OK;
372 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500373}
374
375/**
376 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
377 *
Florin Coraseedc74b2020-07-31 12:32:40 -0700378 * Note that although in the original article srtt and rttvar are scaled
Dave Barach68b0fb02017-02-28 15:15:56 -0500379 * to minimize round-off errors, here we don't. Instead, we rely on
380 * better precision time measurements.
Florin Coraseedc74b2020-07-31 12:32:40 -0700381 *
382 * A known limitation of the algorithm is that a drop in rtt results in a
383 * rttvar increase and bigger RTO.
384 *
385 * mrtt must be provided in @ref TCP_TICK multiples, i.e., in us. Note that
386 * timestamps are measured as ms ticks so they must be converted before
387 * calling this function.
Dave Barach68b0fb02017-02-28 15:15:56 -0500388 */
389static void
390tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
391{
Florin Corasf03a59a2017-06-09 21:07:32 -0700392 int err, diff;
Dave Barach68b0fb02017-02-28 15:15:56 -0500393
Florin Coraseedc74b2020-07-31 12:32:40 -0700394 err = mrtt - tc->srtt;
395 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
396 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
397 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500398}
399
Florin Coras8ddd19b2020-06-07 20:06:56 +0000400static inline void
401tcp_estimate_rtt_us (tcp_connection_t * tc, f64 mrtt)
402{
403 tc->mrtt_us = tc->mrtt_us + (mrtt - tc->mrtt_us) * 0.125;
404}
405
Florin Corasf1762d62017-09-24 19:43:08 -0400406/**
Florin Coras8ddd19b2020-06-07 20:06:56 +0000407 * Update rtt estimate
Dave Barach68b0fb02017-02-28 15:15:56 -0500408 *
Florin Coras8ddd19b2020-06-07 20:06:56 +0000409 * We have potentially three sources of rtt measurements:
Dave Barach68b0fb02017-02-28 15:15:56 -0500410 *
Florin Coras8ddd19b2020-06-07 20:06:56 +0000411 * TSOPT difference between current and echoed timestamp. It has ms
412 * precision and can be computed per ack
413 * ACK timing one sequence number is tracked per rtt with us (micro second)
414 * precision.
415 * rate sample if enabled, all outstanding bytes are tracked with us
416 * precision. Every ack and sack are a rtt sample
Florin Corasf1762d62017-09-24 19:43:08 -0400417 *
Florin Coras8ddd19b2020-06-07 20:06:56 +0000418 * Middle boxes are known to fiddle with TCP options so we give higher
419 * priority to ACK timing.
420 *
421 * For now, rate sample rtts are only used under congestion.
Dave Barach68b0fb02017-02-28 15:15:56 -0500422 */
423static int
Florin Coras1dbda642019-09-11 13:42:57 -0700424tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
Dave Barach68b0fb02017-02-28 15:15:56 -0500425{
426 u32 mrtt = 0;
427
428 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
429 * RTT because they're ambiguous. */
Florin Coras1dbda642019-09-11 13:42:57 -0700430 if (tcp_in_cong_recovery (tc))
Florin Coras3ec66b02018-08-23 16:27:05 -0700431 {
Florin Coras1dbda642019-09-11 13:42:57 -0700432 /* Accept rtt estimates for samples that have not been retransmitted */
Florin Coras8ddd19b2020-06-07 20:06:56 +0000433 if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
434 || (rs->flags & TCP_BTS_IS_RXT))
435 goto done;
436 if (rs->rtt_time)
437 tcp_estimate_rtt_us (tc, rs->rtt_time);
438 mrtt = rs->rtt_time * THZ;
439 goto estimate_rtt;
Florin Coras3ec66b02018-08-23 16:27:05 -0700440 }
Florin Corasf1762d62017-09-24 19:43:08 -0400441
442 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
Dave Barach68b0fb02017-02-28 15:15:56 -0500443 {
Florin Corasefefc6b2018-11-07 12:49:19 -0800444 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
Florin Coras8ddd19b2020-06-07 20:06:56 +0000445 tcp_estimate_rtt_us (tc, sample);
Florin Corasefefc6b2018-11-07 12:49:19 -0800446 mrtt = clib_max ((u32) (sample * THZ), 1);
447 /* Allow measuring of a new RTT */
448 tc->rtt_ts = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500449 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500450 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
451 * snd_una, i.e., the left side of the send window:
Florin Corasf1762d62017-09-24 19:43:08 -0400452 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
453 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
Dave Barach68b0fb02017-02-28 15:15:56 -0500454 {
Florin Coraseedc74b2020-07-31 12:32:40 -0700455 mrtt = clib_max (tcp_tstamp (tc) - tc->rcv_opts.tsecr, 1);
456 mrtt *= TCP_TSTP_TO_HZ;
Dave Barach68b0fb02017-02-28 15:15:56 -0500457 }
458
Florin Coras1dbda642019-09-11 13:42:57 -0700459estimate_rtt:
460
Florin Corasf1762d62017-09-24 19:43:08 -0400461 /* Ignore dubious measurements */
462 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
463 goto done;
464
465 tcp_estimate_rtt (tc, mrtt);
466
467done:
468
Florin Corasf1762d62017-09-24 19:43:08 -0400469 /* If we got here something must've been ACKed so make sure boff is 0,
Florin Coras3ec66b02018-08-23 16:27:05 -0700470 * even if mrtt is not valid since we update the rto lower */
Florin Corasf1762d62017-09-24 19:43:08 -0400471 tc->rto_boff = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700472 tcp_update_rto (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500473
Florin Coras3af90fc2017-05-03 21:09:42 -0700474 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500475}
476
Florin Corasefefc6b2018-11-07 12:49:19 -0800477static void
478tcp_estimate_initial_rtt (tcp_connection_t * tc)
479{
480 u8 thread_index = vlib_num_workers ()? 1 : 0;
481 int mrtt;
482
483 if (tc->rtt_ts)
484 {
485 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
Florin Coras222e1f412019-02-16 20:47:32 -0800486 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
Florin Corasefefc6b2018-11-07 12:49:19 -0800487 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
488 tc->rtt_ts = 0;
489 }
490 else
491 {
Florin Coraseedc74b2020-07-31 12:32:40 -0700492 mrtt = tcp_tstamp (tc) - tc->rcv_opts.tsecr;
493 mrtt = clib_max (mrtt, 1) * TCP_TSTP_TO_HZ;
Florin Coras222e1f412019-02-16 20:47:32 -0800494 /* Due to retransmits we don't know the initial mrtt */
495 if (tc->rto_boff && mrtt > 1 * THZ)
496 mrtt = 1 * THZ;
Florin Corasefefc6b2018-11-07 12:49:19 -0800497 tc->mrtt_us = (f64) mrtt *TCP_TICK;
Florin Corasefefc6b2018-11-07 12:49:19 -0800498 }
499
500 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
Florin Coraseedc74b2020-07-31 12:32:40 -0700501 {
502 /* First measurement as per RFC 6298 */
503 tc->srtt = mrtt;
504 tc->rttvar = mrtt >> 1;
505 }
Florin Coras54ddf432018-12-21 13:54:09 -0800506 tcp_update_rto (tc);
Florin Corasefefc6b2018-11-07 12:49:19 -0800507}
508
Dave Barach68b0fb02017-02-28 15:15:56 -0500509/**
Florin Coras9ece3c02018-11-05 11:06:53 -0800510 * Dequeue bytes for connections that have received acks in last burst
Dave Barach68b0fb02017-02-28 15:15:56 -0500511 */
512static void
Florin Coras9ece3c02018-11-05 11:06:53 -0800513tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
Dave Barach68b0fb02017-02-28 15:15:56 -0500514{
Florin Coras9ece3c02018-11-05 11:06:53 -0800515 u32 thread_index = wrk->vm->thread_index;
516 u32 *pending_deq_acked;
517 tcp_connection_t *tc;
518 int i;
Florin Coras93992a92017-05-24 18:03:56 -0700519
Florin Coras9ece3c02018-11-05 11:06:53 -0800520 if (!vec_len (wrk->pending_deq_acked))
521 return;
Dave Barach68b0fb02017-02-28 15:15:56 -0500522
Florin Coras9ece3c02018-11-05 11:06:53 -0800523 pending_deq_acked = wrk->pending_deq_acked;
524 for (i = 0; i < vec_len (pending_deq_acked); i++)
525 {
526 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
527 tc->flags &= ~TCP_CONN_DEQ_PENDING;
Florin Coras93992a92017-05-24 18:03:56 -0700528
Florin Coras11e9e352019-11-13 19:09:47 -0800529 if (PREDICT_FALSE (!tc->burst_acked))
530 continue;
531
532 /* Dequeue the newly ACKed bytes */
533 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
Florin Coras55e556c2020-10-23 10:45:48 -0700534 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
Florin Coras11e9e352019-11-13 19:09:47 -0800535
Florin Coras6080e0d2020-03-13 20:39:43 +0000536 if (tcp_is_descheduled (tc))
537 tcp_reschedule (tc);
538
Florin Coras11e9e352019-11-13 19:09:47 -0800539 /* If everything has been acked, stop retransmit timer
540 * otherwise update. */
Florin Coras0765d972020-03-18 21:26:41 +0000541 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
Florin Corasb3dce892019-10-30 09:22:14 -0700542
Florin Coras11e9e352019-11-13 19:09:47 -0800543 /* Update pacer based on our new cwnd estimate */
544 tcp_connection_tx_pacer_update (tc);
545
Florin Corasb3dce892019-10-30 09:22:14 -0700546 tc->burst_acked = 0;
Florin Coras9ece3c02018-11-05 11:06:53 -0800547 }
Damjan Marion8bea5892022-04-04 22:40:45 +0200548 vec_set_len (wrk->pending_deq_acked, 0);
Florin Coras9ece3c02018-11-05 11:06:53 -0800549}
550
551static void
552tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
553{
554 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
555 {
556 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
557 tc->flags |= TCP_CONN_DEQ_PENDING;
558 }
Florin Coras558e3e02019-09-06 12:56:58 -0700559 tc->burst_acked += tc->bytes_acked;
Dave Barach68b0fb02017-02-28 15:15:56 -0500560}
561
Florin Coras93992a92017-05-24 18:03:56 -0700562/**
563 * Try to update snd_wnd based on feedback received from peer.
Dave Barach68b0fb02017-02-28 15:15:56 -0500564 *
Florin Coras93992a92017-05-24 18:03:56 -0700565 * If successful, and new window is 'effectively' 0, activate persist
566 * timer.
567 */
Dave Barach68b0fb02017-02-28 15:15:56 -0500568static void
569tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
570{
Florin Coras93992a92017-05-24 18:03:56 -0700571 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
572 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
Florin Coras6792ec02017-03-13 03:49:51 -0700573 if (seq_lt (tc->snd_wl1, seq)
574 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500575 {
576 tc->snd_wnd = snd_wnd;
577 tc->snd_wl1 = seq;
578 tc->snd_wl2 = ack;
Florin Corasa436a422019-08-20 07:09:31 -0700579 TCP_EVT (TCP_EVT_SND_WND, tc);
Florin Coras3e350af2017-03-30 02:54:28 -0700580
Florin Coras9ece3c02018-11-05 11:06:53 -0800581 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
Florin Corasbb292f42017-05-19 09:49:19 -0700582 {
Florin Corasc6a2f1f2022-03-14 14:23:39 -0700583 if (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
Florin Coras0765d972020-03-18 21:26:41 +0000584 {
585 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
Florin Corasc6a2f1f2022-03-14 14:23:39 -0700586
587 /* Set persist timer if we just got 0 wnd. If already set,
588 * update it because some data sent with snd_wnd < snd_mss was
589 * acked. */
590 if (tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
591 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
Florin Coras0765d972020-03-18 21:26:41 +0000592 tcp_persist_timer_set (&wrk->timer_wheel, tc);
593 }
Florin Corasbb292f42017-05-19 09:49:19 -0700594 }
Florin Coras3e350af2017-03-30 02:54:28 -0700595 else
Florin Coras93992a92017-05-24 18:03:56 -0700596 {
Florin Coras70f879d2020-03-13 17:54:42 +0000597 if (PREDICT_FALSE (tcp_timer_is_active (tc, TCP_TIMER_PERSIST)))
Florin Coras0765d972020-03-18 21:26:41 +0000598 {
599 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
600 tcp_persist_timer_reset (&wrk->timer_wheel, tc);
601 }
Florin Coras70f879d2020-03-13 17:54:42 +0000602
Florin Coras6080e0d2020-03-13 20:39:43 +0000603 if (PREDICT_FALSE (tcp_is_descheduled (tc)))
604 tcp_reschedule (tc);
605
Florin Coras9ece3c02018-11-05 11:06:53 -0800606 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
Florin Coras93992a92017-05-24 18:03:56 -0700607 {
608 tc->rto_boff = 0;
609 tcp_update_rto (tc);
610 }
611 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500612 }
613}
614
Florin Corasd2aab832018-05-22 11:39:59 -0700615/**
616 * Init loss recovery/fast recovery.
617 *
618 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
619 * updated in @ref tcp_cc_handle_event after fast retransmit
620 */
Florin Coras36ebcff2019-09-12 18:36:44 -0700621static void
Florin Coras93992a92017-05-24 18:03:56 -0700622tcp_cc_init_congestion (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -0500623{
Florin Coras93992a92017-05-24 18:03:56 -0700624 tcp_fastrecovery_on (tc);
Florin Coras47596832019-03-12 18:58:54 -0700625 tc->snd_congestion = tc->snd_nxt;
Florin Coras62166002018-04-18 16:40:55 -0700626 tc->cwnd_acc_bytes = 0;
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700627 tc->snd_rxt_bytes = 0;
Florin Coras36ebcff2019-09-12 18:36:44 -0700628 tc->rxt_delivered = 0;
629 tc->prr_delivered = 0;
Florin Corasbe237bf2019-09-27 08:16:40 -0700630 tc->prr_start = tc->snd_una;
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700631 tc->prev_ssthresh = tc->ssthresh;
632 tc->prev_cwnd = tc->cwnd;
Florin Coras36ebcff2019-09-12 18:36:44 -0700633
Florin Corasbe237bf2019-09-27 08:16:40 -0700634 tc->snd_rxt_ts = tcp_tstamp (tc);
Florin Coras36ebcff2019-09-12 18:36:44 -0700635 tcp_cc_congestion (tc);
636
637 /* Post retransmit update cwnd to ssthresh and account for the
638 * three segments that have left the network and should've been
639 * buffered at the receiver XXX */
640 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Corascc4d6d02020-07-29 23:03:39 -0700641 tc->cwnd += TCP_DUPACK_THRESHOLD * tc->snd_mss;
Florin Coras36ebcff2019-09-12 18:36:44 -0700642
Florin Corasedfe0ee2019-07-29 18:13:25 -0700643 tc->fr_occurences += 1;
Florin Corasa436a422019-08-20 07:09:31 -0700644 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
Dave Barach68b0fb02017-02-28 15:15:56 -0500645}
Dave Barach68b0fb02017-02-28 15:15:56 -0500646
647static void
Florin Coras93992a92017-05-24 18:03:56 -0700648tcp_cc_congestion_undo (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -0500649{
Florin Coras93992a92017-05-24 18:03:56 -0700650 tc->cwnd = tc->prev_cwnd;
651 tc->ssthresh = tc->prev_ssthresh;
Florin Coraseff6b822019-07-03 19:51:02 -0700652 tcp_cc_undo_recovery (tc);
Florin Coras93992a92017-05-24 18:03:56 -0700653 ASSERT (tc->rto_boff == 0);
Florin Corasa436a422019-08-20 07:09:31 -0700654 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
Florin Coras93992a92017-05-24 18:03:56 -0700655}
Dave Barach68b0fb02017-02-28 15:15:56 -0500656
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700657static inline u8
658tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
Florin Coras93992a92017-05-24 18:03:56 -0700659{
Florin Corasf1762d62017-09-24 19:43:08 -0400660 return (tcp_in_recovery (tc) && tc->rto_boff == 1
Dave Barach2c25a622017-06-26 11:35:07 -0400661 && tc->snd_rxt_ts
Florin Coras93992a92017-05-24 18:03:56 -0700662 && tcp_opts_tstamp (&tc->rcv_opts)
663 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
664}
665
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700666static inline u8
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700667tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
668{
Florin Coras36ebcff2019-09-12 18:36:44 -0700669 return (tcp_cc_is_spurious_timeout_rxt (tc));
670}
671
672static inline u8
Florin Corasbe237bf2019-09-27 08:16:40 -0700673tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
Florin Coras36ebcff2019-09-12 18:36:44 -0700674{
Florin Corasbe237bf2019-09-27 08:16:40 -0700675 if (!has_sack)
676 {
677 /* If of of the two conditions lower hold, reset dupacks because
678 * we're probably after timeout (RFC6582 heuristics).
679 * If Cumulative ack does not cover more than congestion threshold,
680 * and:
681 * 1) The following doesn't hold: The congestion window is greater
682 * than SMSS bytes and the difference between highest_ack
683 * and prev_highest_ack is at most 4*SMSS bytes
684 * 2) Echoed timestamp in the last non-dup ack does not equal the
685 * stored timestamp
686 */
687 if (seq_leq (tc->snd_una, tc->snd_congestion)
688 && ((!(tc->cwnd > tc->snd_mss
689 && tc->bytes_acked <= 4 * tc->snd_mss))
690 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
691 {
692 tc->rcv_dupacks = 0;
693 return 0;
694 }
695 }
Florin Corascc4d6d02020-07-29 23:03:39 -0700696 return tc->sack_sb.lost_bytes || tc->rcv_dupacks >= tc->sack_sb.reorder;
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700697}
698
Florin Coras0dbd5172018-06-25 16:19:34 -0700699static int
Florin Corasb56f24b2022-01-05 12:55:35 -0800700tcp_cc_try_recover (tcp_connection_t *tc)
Florin Coras93992a92017-05-24 18:03:56 -0700701{
Florin Coras321cfa52019-09-12 18:49:44 -0700702 sack_scoreboard_hole_t *hole;
Florin Coras36ebcff2019-09-12 18:36:44 -0700703 u8 is_spurious = 0;
Florin Coras321cfa52019-09-12 18:49:44 -0700704
Florin Coras93992a92017-05-24 18:03:56 -0700705 ASSERT (tcp_in_cong_recovery (tc));
Florin Coras321cfa52019-09-12 18:49:44 -0700706
Florin Coras36ebcff2019-09-12 18:36:44 -0700707 if (tcp_cc_is_spurious_retransmit (tc))
708 {
709 tcp_cc_congestion_undo (tc);
710 is_spurious = 1;
711 }
712
Florin Corasc31dc312019-10-06 14:06:14 -0700713 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
Florin Corasb3dce892019-10-30 09:22:14 -0700714 tc->rcv_dupacks = 0;
Florin Coras8e76dfa2022-01-05 19:54:45 -0800715 tcp_recovery_off (tc);
Florin Corasc31dc312019-10-06 14:06:14 -0700716
Florin Coras36ebcff2019-09-12 18:36:44 -0700717 /* Previous recovery left us congested. Continue sending as part
718 * of the current recovery event with an updated snd_congestion */
Florin Coras8e76dfa2022-01-05 19:54:45 -0800719 if (tc->sack_sb.sacked_bytes && tcp_in_fastrecovery (tc))
Florin Coras36ebcff2019-09-12 18:36:44 -0700720 {
721 tc->snd_congestion = tc->snd_nxt;
Florin Corasb56f24b2022-01-05 12:55:35 -0800722 return -1;
Florin Coras36ebcff2019-09-12 18:36:44 -0700723 }
724
Florin Corasb3dce892019-10-30 09:22:14 -0700725 tc->rxt_delivered = 0;
726 tc->snd_rxt_bytes = 0;
727 tc->snd_rxt_ts = 0;
728 tc->prr_delivered = 0;
729 tc->rtt_ts = 0;
730 tc->flags &= ~TCP_CONN_RXT_PENDING;
731
Florin Coras321cfa52019-09-12 18:49:44 -0700732 hole = scoreboard_first_hole (&tc->sack_sb);
733 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
734 scoreboard_clear (&tc->sack_sb);
735
Florin Coras8e76dfa2022-01-05 19:54:45 -0800736 if (tcp_in_fastrecovery (tc) && !is_spurious)
Florin Coras36ebcff2019-09-12 18:36:44 -0700737 tcp_cc_recovered (tc);
Florin Coras93992a92017-05-24 18:03:56 -0700738
Florin Coras36ebcff2019-09-12 18:36:44 -0700739 tcp_fastrecovery_off (tc);
740 tcp_fastrecovery_first_off (tc);
Florin Coras36ebcff2019-09-12 18:36:44 -0700741 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
Florin Coras93992a92017-05-24 18:03:56 -0700742
743 ASSERT (tc->rto_boff == 0);
744 ASSERT (!tcp_in_cong_recovery (tc));
Florin Coras3eb50622017-07-13 01:24:57 -0400745 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
Florin Coras6080e0d2020-03-13 20:39:43 +0000746
Florin Corasb56f24b2022-01-05 12:55:35 -0800747 return 0;
Florin Coras93992a92017-05-24 18:03:56 -0700748}
749
750static void
Florin Coras52814732019-06-12 15:38:19 -0700751tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
Florin Coras93992a92017-05-24 18:03:56 -0700752{
Florin Coras3eb50622017-07-13 01:24:57 -0400753 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
Florin Coras93992a92017-05-24 18:03:56 -0700754
755 /* Congestion avoidance */
Florin Coras52814732019-06-12 15:38:19 -0700756 tcp_cc_rcv_ack (tc, rs);
Florin Coras93992a92017-05-24 18:03:56 -0700757
758 /* If a cumulative ack, make sure dupacks is 0 */
759 tc->rcv_dupacks = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700760}
761
Florin Corasf03a59a2017-06-09 21:07:32 -0700762/**
763 * One function to rule them all ... and in the darkness bind them
764 */
Florin Coras93992a92017-05-24 18:03:56 -0700765static void
Florin Coras52814732019-06-12 15:38:19 -0700766tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
767 u32 is_dack)
Florin Coras93992a92017-05-24 18:03:56 -0700768{
Florin Corasafef8bf2019-09-11 23:22:29 -0700769 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
Florin Corasf03a59a2017-06-09 21:07:32 -0700770
Florin Coras1de71672019-12-22 09:20:26 -0800771 /* If reneging, wait for timer based retransmits */
772 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
773 return;
774
Florin Corasafef8bf2019-09-11 23:22:29 -0700775 /*
Florin Corasbe237bf2019-09-27 08:16:40 -0700776 * If not in recovery, figure out if we should enter
Florin Corasafef8bf2019-09-11 23:22:29 -0700777 */
Florin Corasbe237bf2019-09-27 08:16:40 -0700778 if (!tcp_in_cong_recovery (tc))
Florin Corasca1c8f32018-05-23 21:01:30 -0700779 {
Florin Corasbe237bf2019-09-27 08:16:40 -0700780 ASSERT (is_dack);
Florin Coras36ebcff2019-09-12 18:36:44 -0700781
Florin Coras93992a92017-05-24 18:03:56 -0700782 tc->rcv_dupacks++;
Florin Corasbe237bf2019-09-27 08:16:40 -0700783 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
784 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
Florin Coras93992a92017-05-24 18:03:56 -0700785
Florin Corasbe237bf2019-09-27 08:16:40 -0700786 if (tcp_should_fastrecover (tc, has_sack))
Dave Barach68b0fb02017-02-28 15:15:56 -0500787 {
Florin Coras93992a92017-05-24 18:03:56 -0700788 tcp_cc_init_congestion (tc);
Florin Coras93992a92017-05-24 18:03:56 -0700789
Florin Corasafef8bf2019-09-11 23:22:29 -0700790 if (has_sack)
Florin Corasbe237bf2019-09-27 08:16:40 -0700791 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700792
Florin Coras36ebcff2019-09-12 18:36:44 -0700793 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
794 tcp_program_retransmit (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500795 }
Florin Coras93992a92017-05-24 18:03:56 -0700796
Florin Corasbe237bf2019-09-27 08:16:40 -0700797 return;
798 }
Florin Corasd2aab832018-05-22 11:39:59 -0700799
Florin Coras93992a92017-05-24 18:03:56 -0700800 /*
Florin Corasb3dce892019-10-30 09:22:14 -0700801 * Already in recovery
Florin Coras93992a92017-05-24 18:03:56 -0700802 */
Florin Coras93992a92017-05-24 18:03:56 -0700803
Florin Coras93992a92017-05-24 18:03:56 -0700804 /*
Florin Corasb56f24b2022-01-05 12:55:35 -0800805 * See if we can exit and stop retransmitting
806 */
807 if (seq_geq (tc->snd_una, tc->snd_congestion))
808 {
809 /* If successfully recovered, treat ack as congestion avoidance ack
810 * and return. Otherwise, we're still congested so process feedback */
811 if (!tcp_cc_try_recover (tc))
812 {
813 tcp_cc_rcv_ack (tc, rs);
814 return;
815 }
816 }
817
818 /*
Florin Corasbe237bf2019-09-27 08:16:40 -0700819 * Process (re)transmit feedback. Output path uses this to decide how much
820 * more data to release into the network
821 */
822 if (has_sack)
823 {
Florin Corasb3dce892019-10-30 09:22:14 -0700824 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
825 tcp_fastrecovery_first_on (tc);
826
Florin Corasbe237bf2019-09-27 08:16:40 -0700827 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
Florin Coras0f8b91f2022-01-05 08:47:11 -0800828 tc->prr_delivered += rs->delivered;
Florin Corasbe237bf2019-09-27 08:16:40 -0700829 }
830 else
831 {
832 if (is_dack)
833 {
834 tc->rcv_dupacks += 1;
835 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
836 }
Florin Coras56cef052020-01-15 20:18:35 +0000837 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
Florin Corasbe237bf2019-09-27 08:16:40 -0700838 tc->snd_rxt_bytes);
839 if (is_dack)
Florin Corasbf1f8b72019-11-04 14:39:33 -0800840 tc->prr_delivered += clib_min (tc->snd_mss,
841 tc->snd_nxt - tc->snd_una);
Florin Corasbe237bf2019-09-27 08:16:40 -0700842 else
Florin Corasbf1f8b72019-11-04 14:39:33 -0800843 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
844 tc->snd_mss *
845 tc->rcv_dupacks);
Florin Corasbe237bf2019-09-27 08:16:40 -0700846
847 /* If partial ack, assume that the first un-acked segment was lost */
848 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
849 tcp_fastrecovery_first_on (tc);
Florin Corasbe237bf2019-09-27 08:16:40 -0700850 }
851
Florin Coras34177e82020-03-20 20:25:37 +0000852 tcp_program_retransmit (tc);
853
Florin Corasb3dce892019-10-30 09:22:14 -0700854 /*
Florin Corasbe237bf2019-09-27 08:16:40 -0700855 * Notify cc of the event
Florin Coras93992a92017-05-24 18:03:56 -0700856 */
Florin Coras93992a92017-05-24 18:03:56 -0700857
Florin Corasbe237bf2019-09-27 08:16:40 -0700858 if (!tc->bytes_acked)
859 {
860 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
861 return;
862 }
863
864 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
865 * reset dupacks to 0. Also needed if in congestion recovery */
866 tc->rcv_dupacks = 0;
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700867
Florin Coras36ebcff2019-09-12 18:36:44 -0700868 if (tcp_in_recovery (tc))
869 tcp_cc_rcv_ack (tc, rs);
Dave Barach68b0fb02017-02-28 15:15:56 -0500870 else
Florin Coras36ebcff2019-09-12 18:36:44 -0700871 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
Florin Corasbe237bf2019-09-27 08:16:40 -0700872}
Dave Barach68b0fb02017-02-28 15:15:56 -0500873
Florin Coras2f04cb92019-12-23 10:03:27 -0800874static void
Florin Coras067f8f92020-01-04 00:53:04 +0000875tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
Florin Coras2f04cb92019-12-23 10:03:27 -0800876{
877 if (!tcp_in_cong_recovery (tc))
878 return;
879
880 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Coras067f8f92020-01-04 00:53:04 +0000881 tcp_rcv_sacks (tc, tc->snd_una);
Florin Coras2f04cb92019-12-23 10:03:27 -0800882
883 tc->bytes_acked = 0;
884
885 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
886 tcp_bt_sample_delivery_rate (tc, rs);
887
888 tcp_cc_handle_event (tc, rs, 1);
889}
890
Florin Corasbe237bf2019-09-27 08:16:40 -0700891/**
892 * Check if duplicate ack as per RFC5681 Sec. 2
893 */
894always_inline u8
895tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
896 u32 prev_snd_una)
897{
898 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
899 && seq_gt (tc->snd_nxt, tc->snd_una)
900 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
901 && (prev_snd_wnd == tc->snd_wnd));
902}
903
904/**
905 * Checks if ack is a congestion control event.
906 */
907static u8
908tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
909 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
910{
911 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
912 * defined to be 'duplicate' as well */
913 *is_dack = tc->sack_sb.last_sacked_bytes
914 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
915
Florin Corasbe237bf2019-09-27 08:16:40 -0700916 return (*is_dack || tcp_in_cong_recovery (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500917}
918
Florin Coras93992a92017-05-24 18:03:56 -0700919/**
920 * Process incoming ACK
921 */
Dave Barach68b0fb02017-02-28 15:15:56 -0500922static int
Florin Coras9ece3c02018-11-05 11:06:53 -0800923tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
Florin Coras7ac053b2018-11-05 15:57:21 -0800924 tcp_header_t * th, u32 * error)
Dave Barach68b0fb02017-02-28 15:15:56 -0500925{
Florin Coras93992a92017-05-24 18:03:56 -0700926 u32 prev_snd_wnd, prev_snd_una;
Florin Coras52814732019-06-12 15:38:19 -0700927 tcp_rate_sample_t rs = { 0 };
Florin Coras93992a92017-05-24 18:03:56 -0700928 u8 is_dack;
Dave Barach68b0fb02017-02-28 15:15:56 -0500929
Florin Corasa436a422019-08-20 07:09:31 -0700930 TCP_EVT (TCP_EVT_CC_STAT, tc);
Florin Corasf03a59a2017-06-09 21:07:32 -0700931
Florin Coras6792ec02017-03-13 03:49:51 -0700932 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
Florin Coras93992a92017-05-24 18:03:56 -0700933 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500934 {
Florin Corasedfe0ee2019-07-29 18:13:25 -0700935 tc->errors.above_ack_wnd += 1;
Florin Coras47596832019-03-12 18:58:54 -0700936 *error = TCP_ERROR_ACK_FUTURE;
Florin Corasa436a422019-08-20 07:09:31 -0700937 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
Florin Coras47596832019-03-12 18:58:54 -0700938 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500939 }
940
Florin Coras6792ec02017-03-13 03:49:51 -0700941 /* If old ACK, probably it's an old dupack */
Florin Coras93992a92017-05-24 18:03:56 -0700942 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500943 {
Florin Corasedfe0ee2019-07-29 18:13:25 -0700944 tc->errors.below_ack_wnd += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500945 *error = TCP_ERROR_ACK_OLD;
Florin Corasa436a422019-08-20 07:09:31 -0700946 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
Florin Coras2f04cb92019-12-23 10:03:27 -0800947
948 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
949 return -1;
950
Florin Coras067f8f92020-01-04 00:53:04 +0000951 tcp_handle_old_ack (tc, &rs);
Florin Coras2f04cb92019-12-23 10:03:27 -0800952
Florin Corasc28764f2017-04-26 00:08:42 -0700953 /* Don't drop yet */
954 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500955 }
956
Florin Coras93992a92017-05-24 18:03:56 -0700957 /*
958 * Looks okay, process feedback
959 */
Florin Corasedfe0ee2019-07-29 18:13:25 -0700960
Florin Coras93992a92017-05-24 18:03:56 -0700961 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500962 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
963
Florin Coras93992a92017-05-24 18:03:56 -0700964 prev_snd_wnd = tc->snd_wnd;
965 prev_snd_una = tc->snd_una;
966 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
967 vnet_buffer (b)->tcp.ack_number,
968 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
969 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
Florin Coras558e3e02019-09-06 12:56:58 -0700970 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
Florin Coras93992a92017-05-24 18:03:56 -0700971 tcp_validate_txf_size (tc, tc->bytes_acked);
Dave Barach68b0fb02017-02-28 15:15:56 -0500972
Florin Corasbbcfaac2019-10-10 13:52:04 -0700973 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Coras1dbda642019-09-11 13:42:57 -0700974 tcp_bt_sample_delivery_rate (tc, &rs);
Florin Coras0f8b91f2022-01-05 08:47:11 -0800975 else
976 rs.delivered = tc->bytes_acked + tc->sack_sb.last_sacked_bytes -
977 tc->sack_sb.last_bytes_delivered;
Florin Coras1dbda642019-09-11 13:42:57 -0700978
Florin Coras8ddd19b2020-06-07 20:06:56 +0000979 if (tc->bytes_acked + tc->sack_sb.last_sacked_bytes)
Florin Coras11e9e352019-11-13 19:09:47 -0800980 {
Florin Coras11e9e352019-11-13 19:09:47 -0800981 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
Florin Coras8ddd19b2020-06-07 20:06:56 +0000982 if (tc->bytes_acked)
983 tcp_program_dequeue (wrk, tc);
Florin Coras11e9e352019-11-13 19:09:47 -0800984 }
Florin Coras93992a92017-05-24 18:03:56 -0700985
Florin Corasa436a422019-08-20 07:09:31 -0700986 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
Florin Coras6534b7a2017-07-18 05:38:03 -0400987
Florin Coras93992a92017-05-24 18:03:56 -0700988 /*
989 * Check if we have congestion event
990 */
991
992 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
Dave Barach68b0fb02017-02-28 15:15:56 -0500993 {
Florin Coras52814732019-06-12 15:38:19 -0700994 tcp_cc_handle_event (tc, &rs, is_dack);
Florin Corasedfe0ee2019-07-29 18:13:25 -0700995 tc->dupacks_in += is_dack;
Florin Corasb2215d62017-08-01 16:56:58 -0700996 if (!tcp_in_cong_recovery (tc))
Florin Corasa9d5bea2018-12-17 08:24:19 -0800997 {
998 *error = TCP_ERROR_ACK_OK;
999 return 0;
1000 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001001 *error = TCP_ERROR_ACK_DUP;
Florin Corasca09d072018-10-01 18:31:02 -07001002 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1003 return 0;
1004 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001005 }
1006
Florin Coras6792ec02017-03-13 03:49:51 -07001007 /*
Florin Coras93992a92017-05-24 18:03:56 -07001008 * Update congestion control (slow start/congestion avoidance)
Florin Coras6792ec02017-03-13 03:49:51 -07001009 */
Florin Coras52814732019-06-12 15:38:19 -07001010 tcp_cc_update (tc, &rs);
Florin Coras00cd22d2018-04-18 13:20:18 -07001011 *error = TCP_ERROR_ACK_OK;
Dave Barach68b0fb02017-02-28 15:15:56 -05001012 return 0;
1013}
1014
Florin Corasb11175d2018-11-09 14:34:08 -08001015static void
1016tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1017{
1018 if (!tcp_disconnect_pending (tc))
1019 {
1020 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1021 tcp_disconnect_pending_on (tc);
1022 }
1023}
1024
1025static void
1026tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1027{
Florin Coras6939d5e2020-02-10 23:22:34 +00001028 u32 thread_index, *pending_disconnects, *pending_resets;
Florin Corasb11175d2018-11-09 14:34:08 -08001029 tcp_connection_t *tc;
1030 int i;
1031
Florin Coras6939d5e2020-02-10 23:22:34 +00001032 if (vec_len (wrk->pending_disconnects))
Florin Corasb11175d2018-11-09 14:34:08 -08001033 {
Florin Coras6939d5e2020-02-10 23:22:34 +00001034 thread_index = wrk->vm->thread_index;
1035 pending_disconnects = wrk->pending_disconnects;
1036 for (i = 0; i < vec_len (pending_disconnects); i++)
1037 {
1038 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1039 tcp_disconnect_pending_off (tc);
1040 session_transport_closing_notify (&tc->connection);
1041 }
Damjan Marion8bea5892022-04-04 22:40:45 +02001042 vec_set_len (wrk->pending_disconnects, 0);
Florin Corasb11175d2018-11-09 14:34:08 -08001043 }
Florin Coras6939d5e2020-02-10 23:22:34 +00001044
1045 if (vec_len (wrk->pending_resets))
1046 {
1047 thread_index = wrk->vm->thread_index;
1048 pending_resets = wrk->pending_resets;
1049 for (i = 0; i < vec_len (pending_resets); i++)
1050 {
1051 tc = tcp_connection_get (pending_resets[i], thread_index);
1052 tcp_disconnect_pending_off (tc);
1053 tcp_handle_rst (tc);
1054 }
Damjan Marion8bea5892022-04-04 22:40:45 +02001055 vec_set_len (wrk->pending_resets, 0);
Florin Coras6939d5e2020-02-10 23:22:34 +00001056 }
Florin Corasb11175d2018-11-09 14:34:08 -08001057}
1058
1059static void
1060tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1061 u32 * error)
1062{
Florin Corasf73d4c22019-06-28 09:18:48 -07001063 /* Reject out-of-order fins */
1064 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1065 return;
1066
Florin Coras3c514d52018-12-22 11:39:33 -08001067 /* Account for the FIN and send ack */
1068 tc->rcv_nxt += 1;
Florin Corascb711a42019-10-16 19:28:17 -07001069 tc->flags |= TCP_CONN_FINRCVD;
Florin Coras26dd6de2019-07-23 23:54:47 -07001070 tcp_program_ack (tc);
Florin Corasb11175d2018-11-09 14:34:08 -08001071 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1072 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
Florin Coras3c514d52018-12-22 11:39:33 -08001073 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
Florin Corasb11175d2018-11-09 14:34:08 -08001074 tcp_program_disconnect (wrk, tc);
Florin Coras0765d972020-03-18 21:26:41 +00001075 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
1076 tcp_cfg.closewait_time);
Florin Corasa436a422019-08-20 07:09:31 -07001077 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
Florin Corasb11175d2018-11-09 14:34:08 -08001078 *error = TCP_ERROR_FIN_RCVD;
1079}
1080
Dave Barach68b0fb02017-02-28 15:15:56 -05001081/** Enqueue data for delivery to application */
Florin Coras0dbd5172018-06-25 16:19:34 -07001082static int
Dave Barach68b0fb02017-02-28 15:15:56 -05001083tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1084 u16 data_len)
1085{
Florin Coras1f152cd2017-08-18 19:28:03 -07001086 int written, error = TCP_ERROR_ENQUEUED;
Dave Barach68b0fb02017-02-28 15:15:56 -05001087
Dave Barach2c25a622017-06-26 11:35:07 -04001088 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
Florin Coras00cd22d2018-04-18 13:20:18 -07001089 ASSERT (data_len);
Florin Coras3cbc04b2017-10-02 00:18:51 -07001090 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1091 1 /* queue event */ , 1);
Dave Barach68b0fb02017-02-28 15:15:56 -05001092
Florin Corasa436a422019-08-20 07:09:31 -07001093 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
Florin Coras6792ec02017-03-13 03:49:51 -07001094
Dave Barach68b0fb02017-02-28 15:15:56 -05001095 /* Update rcv_nxt */
1096 if (PREDICT_TRUE (written == data_len))
1097 {
Florin Coras1f152cd2017-08-18 19:28:03 -07001098 tc->rcv_nxt += written;
Florin Corasc37ce792022-08-29 11:35:53 -07001099 tc->bytes_in += written;
Dave Barach68b0fb02017-02-28 15:15:56 -05001100 }
1101 /* If more data written than expected, account for out-of-order bytes. */
1102 else if (written > data_len)
1103 {
Florin Coras1f152cd2017-08-18 19:28:03 -07001104 tc->rcv_nxt += written;
Florin Corasc37ce792022-08-29 11:35:53 -07001105 tc->bytes_in += data_len;
Florin Corasa436a422019-08-20 07:09:31 -07001106 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
Florin Coras6792ec02017-03-13 03:49:51 -07001107 }
1108 else if (written > 0)
1109 {
1110 /* We've written something but FIFO is probably full now */
1111 tc->rcv_nxt += written;
Florin Corasc37ce792022-08-29 11:35:53 -07001112 tc->bytes_in += written;
Florin Coras1f152cd2017-08-18 19:28:03 -07001113 error = TCP_ERROR_PARTIALLY_ENQUEUED;
Dave Barach68b0fb02017-02-28 15:15:56 -05001114 }
1115 else
1116 {
Florin Corasdfd980f2020-03-26 02:45:39 +00001117 /* Packet made it through for ack processing */
1118 if (tc->rcv_wnd < tc->snd_mss)
1119 return TCP_ERROR_ZERO_RWND;
1120
Dave Barach68b0fb02017-02-28 15:15:56 -05001121 return TCP_ERROR_FIFO_FULL;
1122 }
1123
Florin Coras6792ec02017-03-13 03:49:51 -07001124 /* Update SACK list if need be */
Florin Coras607ece32021-04-22 21:10:02 -07001125 if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
Florin Coras6792ec02017-03-13 03:49:51 -07001126 {
1127 /* Remove SACK blocks that have been delivered */
1128 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1129 }
1130
Florin Coras1f152cd2017-08-18 19:28:03 -07001131 return error;
Dave Barach68b0fb02017-02-28 15:15:56 -05001132}
1133
1134/** Enqueue out-of-order data */
Florin Coras0dbd5172018-06-25 16:19:34 -07001135static int
Dave Barach68b0fb02017-02-28 15:15:56 -05001136tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1137 u16 data_len)
1138{
Florin Coras288eaab2019-02-03 15:26:14 -08001139 session_t *s0;
Florin Coras3eb50622017-07-13 01:24:57 -04001140 int rv, offset;
Florin Coras6792ec02017-03-13 03:49:51 -07001141
Florin Corasf03a59a2017-06-09 21:07:32 -07001142 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
Florin Coras00cd22d2018-04-18 13:20:18 -07001143 ASSERT (data_len);
Dave Barach68b0fb02017-02-28 15:15:56 -05001144
Florin Corasf03a59a2017-06-09 21:07:32 -07001145 /* Enqueue out-of-order data with relative offset */
Florin Coras3cbc04b2017-10-02 00:18:51 -07001146 rv = session_enqueue_stream_connection (&tc->connection, b,
1147 vnet_buffer (b)->tcp.seq_number -
1148 tc->rcv_nxt, 0 /* queue event */ ,
1149 0);
Florin Coras6792ec02017-03-13 03:49:51 -07001150
1151 /* Nothing written */
1152 if (rv)
1153 {
Florin Corasa436a422019-08-20 07:09:31 -07001154 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
Florin Coras6792ec02017-03-13 03:49:51 -07001155 return TCP_ERROR_FIFO_FULL;
1156 }
1157
Florin Corasa436a422019-08-20 07:09:31 -07001158 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
Florin Corasedfe0ee2019-07-29 18:13:25 -07001159 tc->bytes_in += data_len;
Dave Barach68b0fb02017-02-28 15:15:56 -05001160
1161 /* Update SACK list if in use */
Florin Coras93992a92017-05-24 18:03:56 -07001162 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05001163 {
1164 ooo_segment_t *newest;
1165 u32 start, end;
1166
Florin Corascea194d2017-10-02 00:18:51 -07001167 s0 = session_get (tc->c_s_index, tc->c_thread_index);
Florin Corasf6d68ed2017-05-07 19:12:02 -07001168
Dave Barach68b0fb02017-02-28 15:15:56 -05001169 /* Get the newest segment from the fifo */
Florin Coras288eaab2019-02-03 15:26:14 -08001170 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
Florin Corasf03a59a2017-06-09 21:07:32 -07001171 if (newest)
1172 {
Sirshak Das28aa5392019-02-05 01:33:33 -06001173 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
Florin Coras3eb50622017-07-13 01:24:57 -04001174 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1175 start = tc->rcv_nxt + offset;
Florin Coras288eaab2019-02-03 15:26:14 -08001176 end = start + ooo_segment_length (s0->rx_fifo, newest);
Florin Corasf03a59a2017-06-09 21:07:32 -07001177 tcp_update_sack_list (tc, start, end);
Florin Coras288eaab2019-02-03 15:26:14 -08001178 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
Florin Corasa436a422019-08-20 07:09:31 -07001179 TCP_EVT (TCP_EVT_CC_SACKS, tc);
Florin Corasf03a59a2017-06-09 21:07:32 -07001180 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001181 }
1182
Florin Coras00cd22d2018-04-18 13:20:18 -07001183 return TCP_ERROR_ENQUEUED_OOO;
Dave Barach68b0fb02017-02-28 15:15:56 -05001184}
1185
Dave Barach68b0fb02017-02-28 15:15:56 -05001186static int
Florin Corasb2215d62017-08-01 16:56:58 -07001187tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1188{
Florin Coras1f152cd2017-08-18 19:28:03 -07001189 u32 discard, first = b->current_length;
Florin Corasb2215d62017-08-01 16:56:58 -07001190 vlib_main_t *vm = vlib_get_main ();
1191
Florin Coras1f152cd2017-08-18 19:28:03 -07001192 /* Handle multi-buffer segments */
Florin Corasb2215d62017-08-01 16:56:58 -07001193 if (n_bytes_to_drop > b->current_length)
1194 {
1195 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1196 return -1;
1197 do
1198 {
1199 discard = clib_min (n_bytes_to_drop, b->current_length);
1200 vlib_buffer_advance (b, discard);
1201 b = vlib_get_buffer (vm, b->next_buffer);
1202 n_bytes_to_drop -= discard;
1203 }
1204 while (n_bytes_to_drop);
Florin Coras1f152cd2017-08-18 19:28:03 -07001205 if (n_bytes_to_drop > first)
1206 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
Florin Corasb2215d62017-08-01 16:56:58 -07001207 }
Florin Coras1f152cd2017-08-18 19:28:03 -07001208 else
1209 vlib_buffer_advance (b, n_bytes_to_drop);
1210 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
Florin Corasb2215d62017-08-01 16:56:58 -07001211 return 0;
1212}
1213
Florin Coras00cd22d2018-04-18 13:20:18 -07001214/**
1215 * Receive buffer for connection and handle acks
1216 *
1217 * It handles both in order or out-of-order data.
1218 */
Florin Corasb2215d62017-08-01 16:56:58 -07001219static int
Florin Coras7ac053b2018-11-05 15:57:21 -08001220tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1221 vlib_buffer_t * b)
Dave Barach68b0fb02017-02-28 15:15:56 -05001222{
Florin Coras00cd22d2018-04-18 13:20:18 -07001223 u32 error, n_bytes_to_drop, n_data_bytes;
Florin Coras6534b7a2017-07-18 05:38:03 -04001224
1225 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1226 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1227 ASSERT (n_data_bytes);
Florin Corasedfe0ee2019-07-29 18:13:25 -07001228 tc->data_segs_in += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001229
Florin Coras1f85dad2020-11-05 13:39:48 -08001230 /* Make sure we don't consume trailing bytes */
Florin Corasab0a87f2020-11-09 19:03:09 -08001231 if (PREDICT_FALSE (b->current_length > n_data_bytes))
Florin Coras1f85dad2020-11-05 13:39:48 -08001232 b->current_length = n_data_bytes;
1233
Dave Barach68b0fb02017-02-28 15:15:56 -05001234 /* Handle out-of-order data */
1235 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1236 {
Florin Coras6792ec02017-03-13 03:49:51 -07001237 /* Old sequence numbers allowed through because they overlapped
1238 * the rx window */
1239 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
Dave Barach68b0fb02017-02-28 15:15:56 -05001240 {
Florin Coras00cd22d2018-04-18 13:20:18 -07001241 /* Completely in the past (possible retransmit). Ack
1242 * retransmissions since we may not have any data to send */
Florin Corasf03a59a2017-06-09 21:07:32 -07001243 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
Florin Coras6534b7a2017-07-18 05:38:03 -04001244 {
Florin Coras7fd59cc2020-03-12 15:50:57 +00001245 tcp_program_dupack (tc);
1246 tc->errors.below_data_wnd++;
Florin Coras00cd22d2018-04-18 13:20:18 -07001247 error = TCP_ERROR_SEGMENT_OLD;
Florin Coras6534b7a2017-07-18 05:38:03 -04001248 goto done;
1249 }
Dave Barach259cdae2017-05-15 16:27:05 -04001250
Florin Coras00cd22d2018-04-18 13:20:18 -07001251 /* Chop off the bytes in the past and see if what is left
1252 * can be enqueued in order */
Florin Corasdb84e572017-05-09 18:54:52 -07001253 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1254 n_data_bytes -= n_bytes_to_drop;
Dave Barach2c25a622017-06-26 11:35:07 -04001255 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
Florin Corasb2215d62017-08-01 16:56:58 -07001256 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
Florin Coras00cd22d2018-04-18 13:20:18 -07001257 {
1258 error = TCP_ERROR_SEGMENT_OLD;
Florin Coras00cd22d2018-04-18 13:20:18 -07001259 goto done;
1260 }
Florin Corasdb84e572017-05-09 18:54:52 -07001261 goto in_order;
Dave Barach68b0fb02017-02-28 15:15:56 -05001262 }
1263
Florin Coras00cd22d2018-04-18 13:20:18 -07001264 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
Florin Coras6792ec02017-03-13 03:49:51 -07001265 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
Florin Coras26dd6de2019-07-23 23:54:47 -07001266 tcp_program_dupack (tc);
Florin Corasa436a422019-08-20 07:09:31 -07001267 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
Florin Corasedfe0ee2019-07-29 18:13:25 -07001268 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1269 tc->rcv_las + tc->rcv_wnd);
Dave Barach68b0fb02017-02-28 15:15:56 -05001270 goto done;
1271 }
1272
Florin Corasdb84e572017-05-09 18:54:52 -07001273in_order:
1274
Dave Barach68b0fb02017-02-28 15:15:56 -05001275 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1276 * segments can be enqueued after fifo tail offset changes. */
1277 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
Florin Coras26dd6de2019-07-23 23:54:47 -07001278 tcp_program_ack (tc);
Florin Coras3e350af2017-03-30 02:54:28 -07001279
Dave Barach68b0fb02017-02-28 15:15:56 -05001280done:
1281 return error;
1282}
1283
Clement Durand6cf260c2017-04-13 13:27:04 +02001284typedef struct
1285{
1286 tcp_header_t tcp_header;
1287 tcp_connection_t tcp_connection;
1288} tcp_rx_trace_t;
1289
Florin Coras0dbd5172018-06-25 16:19:34 -07001290static u8 *
Clement Durand6cf260c2017-04-13 13:27:04 +02001291format_tcp_rx_trace (u8 * s, va_list * args)
1292{
1293 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1294 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1295 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
Florin Coras30928f82020-01-27 19:21:28 -08001296 tcp_connection_t *tc = &t->tcp_connection;
Christophe Fontained3c008d2017-10-02 18:10:54 +02001297 u32 indent = format_get_indent (s);
Clement Durand6cf260c2017-04-13 13:27:04 +02001298
Filip Tehlarbc4dc162023-04-17 12:22:12 +02001299 if (!tc->c_lcl_port)
1300 s = format (s, "no tcp connection\n%U%U", format_white_space, indent,
1301 format_tcp_header, &t->tcp_header, 128);
1302 else
1303 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
1304 format_tcp_state, tc->state, format_white_space, indent,
1305 format_tcp_header, &t->tcp_header, 128);
Clement Durand6cf260c2017-04-13 13:27:04 +02001306
1307 return s;
1308}
1309
Florin Coras0dbd5172018-06-25 16:19:34 -07001310static u8 *
Clement Durand6cf260c2017-04-13 13:27:04 +02001311format_tcp_rx_trace_short (u8 * s, va_list * args)
1312{
1313 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1314 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1315 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1316
1317 s = format (s, "%d -> %d (%U)",
Florin Coras4df38712018-06-20 12:44:16 -07001318 clib_net_to_host_u16 (t->tcp_header.dst_port),
1319 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
Florin Corasbb292f42017-05-19 09:49:19 -07001320 t->tcp_connection.state);
Clement Durand6cf260c2017-04-13 13:27:04 +02001321
1322 return s;
1323}
1324
Florin Coras4df38712018-06-20 12:44:16 -07001325static void
Florin Coras82b13a82017-04-25 11:58:06 -07001326tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1327 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1328{
1329 if (tc0)
1330 {
Dave Barach178cf492018-11-13 16:34:13 -05001331 clib_memcpy_fast (&t0->tcp_connection, tc0,
1332 sizeof (t0->tcp_connection));
Florin Coras82b13a82017-04-25 11:58:06 -07001333 }
1334 else
1335 {
1336 th0 = tcp_buffer_hdr (b0);
1337 }
Dave Barach178cf492018-11-13 16:34:13 -05001338 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
Florin Coras82b13a82017-04-25 11:58:06 -07001339}
1340
Florin Coras4df38712018-06-20 12:44:16 -07001341static void
1342tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
1343 vlib_frame_t * frame, u8 is_ip4)
1344{
1345 u32 *from, n_left;
1346
1347 n_left = frame->n_vectors;
1348 from = vlib_frame_vector_args (frame);
1349
1350 while (n_left >= 1)
1351 {
1352 tcp_connection_t *tc0;
1353 tcp_rx_trace_t *t0;
1354 tcp_header_t *th0;
1355 vlib_buffer_t *b0;
1356 u32 bi0;
1357
1358 bi0 = from[0];
1359 b0 = vlib_get_buffer (vm, bi0);
1360
1361 if (b0->flags & VLIB_BUFFER_IS_TRACED)
1362 {
1363 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
1364 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1365 vm->thread_index);
1366 th0 = tcp_buffer_hdr (b0);
1367 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
1368 }
1369
1370 from += 1;
1371 n_left -= 1;
1372 }
1373}
1374
Dave Barach68b0fb02017-02-28 15:15:56 -05001375always_inline uword
1376tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
Florin Coras4df38712018-06-20 12:44:16 -07001377 vlib_frame_t * frame, int is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05001378{
Florin Coras0242d302022-12-22 15:03:44 -08001379 u32 thread_index = vm->thread_index, n_left_from, *from;
Florin Coras9ece3c02018-11-05 11:06:53 -08001380 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
Florin Coras974b4682021-04-22 18:53:30 -07001381 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
Florin Coras00cd22d2018-04-18 13:20:18 -07001382 u16 err_counters[TCP_N_ERROR] = { 0 };
Dave Barach68b0fb02017-02-28 15:15:56 -05001383
Florin Coras4df38712018-06-20 12:44:16 -07001384 if (node->flags & VLIB_NODE_FLAG_TRACE)
1385 tcp_established_trace_frame (vm, node, frame, is_ip4);
1386
Florin Coras974b4682021-04-22 18:53:30 -07001387 from = vlib_frame_vector_args (frame);
Florin Coras4df38712018-06-20 12:44:16 -07001388 n_left_from = frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05001389
Florin Coras974b4682021-04-22 18:53:30 -07001390 vlib_get_buffers (vm, from, bufs, n_left_from);
1391 b = bufs;
1392
Dave Barach68b0fb02017-02-28 15:15:56 -05001393 while (n_left_from > 0)
1394 {
Florin Coras974b4682021-04-22 18:53:30 -07001395 u32 error = TCP_ERROR_ACK_OK;
1396 tcp_connection_t *tc;
1397 tcp_header_t *th;
Dave Barach68b0fb02017-02-28 15:15:56 -05001398
Florin Coras7ac053b2018-11-05 15:57:21 -08001399 if (n_left_from > 1)
Dave Barach68b0fb02017-02-28 15:15:56 -05001400 {
Florin Coras974b4682021-04-22 18:53:30 -07001401 vlib_prefetch_buffer_header (b[1], LOAD);
1402 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
Dave Barach68b0fb02017-02-28 15:15:56 -05001403 }
1404
Florin Coras974b4682021-04-22 18:53:30 -07001405 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
1406 thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -08001407
Florin Coras974b4682021-04-22 18:53:30 -07001408 if (PREDICT_FALSE (tc == 0))
Florin Coras7ac053b2018-11-05 15:57:21 -08001409 {
Florin Coras974b4682021-04-22 18:53:30 -07001410 error = TCP_ERROR_INVALID_CONNECTION;
Florin Coras7ac053b2018-11-05 15:57:21 -08001411 goto done;
1412 }
1413
Florin Coras974b4682021-04-22 18:53:30 -07001414 th = tcp_buffer_hdr (b[0]);
Florin Coras7ac053b2018-11-05 15:57:21 -08001415
1416 /* TODO header prediction fast path */
1417
1418 /* 1-4: check SEQ, RST, SYN */
Florin Coras974b4682021-04-22 18:53:30 -07001419 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], th, &error)))
Florin Coras7ac053b2018-11-05 15:57:21 -08001420 {
Florin Coras974b4682021-04-22 18:53:30 -07001421 TCP_EVT (TCP_EVT_SEG_INVALID, tc, vnet_buffer (b[0])->tcp);
Florin Coras7ac053b2018-11-05 15:57:21 -08001422 goto done;
1423 }
1424
1425 /* 5: check the ACK field */
Florin Coras974b4682021-04-22 18:53:30 -07001426 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc, b[0], th, &error)))
Florin Coras7ac053b2018-11-05 15:57:21 -08001427 goto done;
1428
1429 /* 6: check the URG bit TODO */
1430
1431 /* 7: process the segment text */
Florin Coras974b4682021-04-22 18:53:30 -07001432 if (vnet_buffer (b[0])->tcp.data_len)
1433 error = tcp_segment_rcv (wrk, tc, b[0]);
Florin Coras7ac053b2018-11-05 15:57:21 -08001434
1435 /* 8: check the FIN bit */
Florin Coras974b4682021-04-22 18:53:30 -07001436 if (PREDICT_FALSE (tcp_is_fin (th)))
1437 tcp_rcv_fin (wrk, tc, b[0], &error);
Florin Coras7ac053b2018-11-05 15:57:21 -08001438
1439 done:
Florin Coras974b4682021-04-22 18:53:30 -07001440 tcp_inc_err_counter (err_counters, error, 1);
1441
1442 n_left_from -= 1;
1443 b += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001444 }
1445
Florin Coras0242d302022-12-22 15:03:44 -08001446 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
Florin Coras00cd22d2018-04-18 13:20:18 -07001447 tcp_store_err_counters (established, err_counters);
Florin Coras9ece3c02018-11-05 11:06:53 -08001448 tcp_handle_postponed_dequeues (wrk);
Florin Corasb11175d2018-11-09 14:34:08 -08001449 tcp_handle_disconnects (wrk);
Florin Coras974b4682021-04-22 18:53:30 -07001450 vlib_buffer_free (vm, from, frame->n_vectors);
Florin Coras4df38712018-06-20 12:44:16 -07001451
1452 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05001453}
1454
Filip Tehlare275bed2019-03-06 00:06:56 -08001455VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
1456 vlib_node_runtime_t * node,
1457 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05001458{
1459 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1460}
1461
Filip Tehlare275bed2019-03-06 00:06:56 -08001462VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
1463 vlib_node_runtime_t * node,
1464 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05001465{
1466 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1467}
1468
1469/* *INDENT-OFF* */
Florin Coras9a1fbb52023-06-08 20:47:11 -07001470VLIB_REGISTER_NODE (tcp4_established_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05001471 .name = "tcp4-established",
1472 /* Takes a vector of packets. */
1473 .vector_size = sizeof (u32),
Florin Corase69f4952017-03-07 10:06:24 -08001474 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00001475 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02001476 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05001477};
1478/* *INDENT-ON* */
1479
Dave Barach68b0fb02017-02-28 15:15:56 -05001480/* *INDENT-OFF* */
Florin Coras9a1fbb52023-06-08 20:47:11 -07001481VLIB_REGISTER_NODE (tcp6_established_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05001482 .name = "tcp6-established",
1483 /* Takes a vector of packets. */
1484 .vector_size = sizeof (u32),
1485 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00001486 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02001487 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05001488};
1489/* *INDENT-ON* */
1490
1491
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001492static u8
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001493tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
1494 tcp_header_t * hdr)
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001495{
Florin Corascea194d2017-10-02 00:18:51 -07001496 transport_connection_t *tmp = 0;
1497 u64 handle;
1498
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001499 if (!tc)
1500 return 1;
1501
Florin Coras70131132017-11-27 02:43:30 -08001502 /* Proxy case */
1503 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
1504 return 1;
1505
Florin Coras07df7912019-11-07 08:26:06 -08001506 u8 is_ip_valid = 0, val_l, val_r;
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001507
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001508 if (tc->connection.is_ip4)
1509 {
1510 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
Florin Coras07df7912019-11-07 08:26:06 -08001511
1512 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
1513 &tc->connection.lcl_ip.ip4);
1514 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
1515 val_r = !ip4_address_compare (&ip4_hdr->src_address,
1516 &tc->connection.rmt_ip.ip4);
1517 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1518 is_ip_valid = val_l && val_r;
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001519 }
1520 else
1521 {
1522 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
Florin Coras07df7912019-11-07 08:26:06 -08001523
1524 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
1525 &tc->connection.lcl_ip.ip6);
1526 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
1527 val_r = !ip6_address_compare (&ip6_hdr->src_address,
1528 &tc->connection.rmt_ip.ip6);
1529 val_r = val_r || tc->state == TCP_STATE_LISTEN;
1530 is_ip_valid = val_l && val_r;
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001531 }
1532
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001533 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1534 && (tc->state == TCP_STATE_LISTEN
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001535 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001536
1537 if (!is_valid)
1538 {
Florin Corascea194d2017-10-02 00:18:51 -07001539 handle = session_lookup_half_open_handle (&tc->connection);
1540 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
Florin Coras3cbc04b2017-10-02 00:18:51 -07001541 tc->c_proto, tc->c_is_ip4);
Florin Corascea194d2017-10-02 00:18:51 -07001542
1543 if (tmp)
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001544 {
1545 if (tmp->lcl_port == hdr->dst_port
1546 && tmp->rmt_port == hdr->src_port)
1547 {
Florin Corascea194d2017-10-02 00:18:51 -07001548 TCP_DBG ("half-open is valid!");
Ryujiro Shibuya3ea17d52019-11-05 07:24:32 +00001549 is_valid = 1;
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001550 }
1551 }
1552 }
1553 return is_valid;
1554}
1555
1556/**
1557 * Lookup transport connection
1558 */
1559static tcp_connection_t *
Florin Corascea194d2017-10-02 00:18:51 -07001560tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
1561 u8 is_ip4)
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001562{
1563 tcp_header_t *tcp;
1564 transport_connection_t *tconn;
1565 tcp_connection_t *tc;
Florin Corasdff48db2017-11-19 18:06:58 -08001566 u8 is_filtered = 0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001567 if (is_ip4)
1568 {
1569 ip4_header_t *ip4;
1570 ip4 = vlib_buffer_get_current (b);
1571 tcp = ip4_next_header (ip4);
Florin Corascea194d2017-10-02 00:18:51 -07001572 tconn = session_lookup_connection_wt4 (fib_index,
1573 &ip4->dst_address,
1574 &ip4->src_address,
1575 tcp->dst_port,
1576 tcp->src_port,
1577 TRANSPORT_PROTO_TCP,
Florin Corasdff48db2017-11-19 18:06:58 -08001578 thread_index, &is_filtered);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001579 tc = tcp_get_connection_from_transport (tconn);
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001580 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001581 }
1582 else
1583 {
1584 ip6_header_t *ip6;
1585 ip6 = vlib_buffer_get_current (b);
1586 tcp = ip6_next_header (ip6);
Florin Corascea194d2017-10-02 00:18:51 -07001587 tconn = session_lookup_connection_wt6 (fib_index,
1588 &ip6->dst_address,
1589 &ip6->src_address,
1590 tcp->dst_port,
1591 tcp->src_port,
1592 TRANSPORT_PROTO_TCP,
Florin Corasdff48db2017-11-19 18:06:58 -08001593 thread_index, &is_filtered);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001594 tc = tcp_get_connection_from_transport (tconn);
Srikanth Akulacf4c2102019-11-06 18:53:13 -08001595 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001596 }
1597 return tc;
1598}
1599
Yu Pingb092b772019-12-27 04:04:33 +08001600static tcp_connection_t *
1601tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
1602{
1603 session_t *s;
1604
1605 if (is_ip4)
1606 {
1607 ip4_header_t *ip4 = vlib_buffer_get_current (b);
1608 tcp_header_t *tcp = tcp_buffer_hdr (b);
1609 s = session_lookup_listener4 (fib_index,
1610 &ip4->dst_address,
1611 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1612 }
1613 else
1614 {
1615 ip6_header_t *ip6 = vlib_buffer_get_current (b);
1616 tcp_header_t *tcp = tcp_buffer_hdr (b);
1617 s = session_lookup_listener6 (fib_index,
1618 &ip6->dst_address,
1619 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
1620
1621 }
1622 if (PREDICT_TRUE (s != 0))
1623 return tcp_get_connection_from_transport (transport_get_listener
1624 (TRANSPORT_PROTO_TCP,
1625 s->connection_index));
1626 else
1627 return 0;
1628}
1629
Florin Corasb636abe2021-05-04 17:08:49 -07001630static void
1631tcp46_syn_sent_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1632 u32 *from, u32 n_bufs)
1633{
1634 tcp_connection_t *tc = 0;
1635 tcp_rx_trace_t *t;
1636 vlib_buffer_t *b;
1637 int i;
1638
1639 for (i = 0; i < n_bufs; i++)
1640 {
1641 b = vlib_get_buffer (vm, from[i]);
1642 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
1643 continue;
1644 tc =
1645 tcp_half_open_connection_get (vnet_buffer (b)->tcp.connection_index);
1646 t = vlib_add_trace (vm, node, b, sizeof (*t));
1647 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
1648 }
1649}
1650
Simon Zhang1146ff42019-09-02 22:54:00 +08001651always_inline void
1652tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
1653{
1654 vnet_main_t *vnm = vnet_get_main ();
1655 const dpo_id_t *dpo;
1656 const load_balance_t *lb;
1657 vnet_hw_interface_t *hw_if;
1658 u32 sw_if_idx, lb_idx;
1659
1660 if (is_ipv4)
1661 {
1662 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
1663 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
1664 }
1665 else
1666 {
1667 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
1668 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
1669 }
1670
1671 lb = load_balance_get (lb_idx);
Simon Zhang79bfb9e2019-12-24 20:02:20 +08001672 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
1673 return;
Simon Zhang1146ff42019-09-02 22:54:00 +08001674 dpo = load_balance_get_bucket_i (lb, 0);
1675
Simon Zhang79bfb9e2019-12-24 20:02:20 +08001676 sw_if_idx = dpo_get_urpf (dpo);
1677 if (PREDICT_FALSE (sw_if_idx == ~0))
1678 return;
Simon Zhang1146ff42019-09-02 22:54:00 +08001679
Simon Zhang79bfb9e2019-12-24 20:02:20 +08001680 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
Damjan Mariond4f88cc2022-01-05 01:52:38 +01001681 if (hw_if->caps & VNET_HW_IF_CAP_TCP_GSO)
Florin Corasbbcfaac2019-10-10 13:52:04 -07001682 tc->cfg_flags |= TCP_CFG_F_TSO;
Simon Zhang1146ff42019-09-02 22:54:00 +08001683}
1684
Filip Tehlarbc4dc162023-04-17 12:22:12 +02001685static void
1686tcp_input_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
1687 vlib_buffer_t **bs, u16 *nexts, u32 n_bufs, u8 is_ip4)
1688{
1689 tcp_connection_t *tc;
1690 tcp_header_t *tcp;
1691 tcp_rx_trace_t *t;
1692 u8 flags;
1693 int i;
1694
1695 for (i = 0; i < n_bufs; i++)
1696 {
1697 if (!(bs[i]->flags & VLIB_BUFFER_IS_TRACED))
1698 continue;
1699
1700 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
1701 if (nexts[i] == TCP_INPUT_NEXT_DROP || nexts[i] == TCP_INPUT_NEXT_PUNT ||
1702 nexts[i] == TCP_INPUT_NEXT_RESET)
1703 {
1704 tc = 0;
1705 }
1706 else
1707 {
1708 flags = vnet_buffer (bs[i])->tcp.flags;
1709
1710 if (flags == TCP_STATE_LISTEN)
1711 tc = tcp_listener_get (vnet_buffer (bs[i])->tcp.connection_index);
1712 else if (flags == TCP_STATE_SYN_SENT)
1713 tc = tcp_half_open_connection_get (
1714 vnet_buffer (bs[i])->tcp.connection_index);
1715 else
1716 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
1717 vm->thread_index);
1718 }
1719 tcp = tcp_buffer_hdr (bs[i]);
1720 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
1721 }
1722}
1723
Dave Barach68b0fb02017-02-28 15:15:56 -05001724always_inline uword
Florin Corasb636abe2021-05-04 17:08:49 -07001725tcp46_syn_sent_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1726 vlib_frame_t *frame, int is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05001727{
Florin Coras0242d302022-12-22 15:03:44 -08001728 u32 n_left_from, *from, thread_index = vm->thread_index;
Florin Corasb636abe2021-05-04 17:08:49 -07001729 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1730 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
Dave Barach68b0fb02017-02-28 15:15:56 -05001731
Florin Corasb636abe2021-05-04 17:08:49 -07001732 from = vlib_frame_vector_args (frame);
1733 n_left_from = frame->n_vectors;
1734
1735 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
1736 tcp46_syn_sent_trace_frame (vm, node, from, n_left_from);
1737
1738 vlib_get_buffers (vm, from, bufs, n_left_from);
1739 b = bufs;
Dave Barach68b0fb02017-02-28 15:15:56 -05001740
Dave Barach68b0fb02017-02-28 15:15:56 -05001741 while (n_left_from > 0)
1742 {
Florin Corasb636abe2021-05-04 17:08:49 -07001743 u32 ack, seq, error = TCP_ERROR_NONE;
1744 tcp_connection_t *tc, *new_tc;
1745 tcp_header_t *tcp;
Dave Barach68b0fb02017-02-28 15:15:56 -05001746
Florin Corasb636abe2021-05-04 17:08:49 -07001747 tc = tcp_half_open_connection_get (
1748 vnet_buffer (b[0])->tcp.connection_index);
1749 if (PREDICT_FALSE (tc == 0))
Dave Barach68b0fb02017-02-28 15:15:56 -05001750 {
Florin Corasb636abe2021-05-04 17:08:49 -07001751 error = TCP_ERROR_INVALID_CONNECTION;
Florin Coras7ac053b2018-11-05 15:57:21 -08001752 goto drop;
Dave Barach68b0fb02017-02-28 15:15:56 -05001753 }
1754
Ivan Shvedunov4beb1c62021-01-16 03:43:01 +03001755 /* Half-open completed or cancelled recently but the connection
1756 * was't removed yet by the owning thread */
Florin Corasb636abe2021-05-04 17:08:49 -07001757 if (PREDICT_FALSE (tc->flags & TCP_CONN_HALF_OPEN_DONE))
Florin Coras7ac053b2018-11-05 15:57:21 -08001758 {
Florin Corasb636abe2021-05-04 17:08:49 -07001759 error = TCP_ERROR_SPURIOUS_SYN_ACK;
Florin Coras7ac053b2018-11-05 15:57:21 -08001760 goto drop;
1761 }
1762
Florin Corasb636abe2021-05-04 17:08:49 -07001763 ack = vnet_buffer (b[0])->tcp.ack_number;
1764 seq = vnet_buffer (b[0])->tcp.seq_number;
1765 tcp = tcp_buffer_hdr (b[0]);
Florin Coras7ac053b2018-11-05 15:57:21 -08001766
1767 /* Crude check to see if the connection handle does not match
1768 * the packet. Probably connection just switched to established */
Florin Corasb636abe2021-05-04 17:08:49 -07001769 if (PREDICT_FALSE (tcp->dst_port != tc->c_lcl_port ||
1770 tcp->src_port != tc->c_rmt_port))
Florin Coras7ac053b2018-11-05 15:57:21 -08001771 {
Florin Corasb636abe2021-05-04 17:08:49 -07001772 error = TCP_ERROR_INVALID_CONNECTION;
Florin Coras7ac053b2018-11-05 15:57:21 -08001773 goto drop;
1774 }
1775
Florin Corasb636abe2021-05-04 17:08:49 -07001776 if (PREDICT_FALSE (!tcp_ack (tcp) && !tcp_rst (tcp) && !tcp_syn (tcp)))
Florin Coras7ac053b2018-11-05 15:57:21 -08001777 {
Florin Corasb636abe2021-05-04 17:08:49 -07001778 error = TCP_ERROR_SEGMENT_INVALID;
Florin Coras7ac053b2018-11-05 15:57:21 -08001779 goto drop;
1780 }
1781
Florin Coras3c514d52018-12-22 11:39:33 -08001782 /* SYNs consume sequence numbers */
Florin Corasb636abe2021-05-04 17:08:49 -07001783 vnet_buffer (b[0])->tcp.seq_end += tcp_is_syn (tcp);
Florin Coras7ac053b2018-11-05 15:57:21 -08001784
1785 /*
1786 * 1. check the ACK bit
1787 */
1788
1789 /*
1790 * If the ACK bit is set
1791 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
1792 * the RST bit is set, if so drop the segment and return)
1793 * <SEQ=SEG.ACK><CTL=RST>
1794 * and discard the segment. Return.
1795 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
1796 */
Florin Corasb636abe2021-05-04 17:08:49 -07001797 if (tcp_ack (tcp))
Florin Coras7ac053b2018-11-05 15:57:21 -08001798 {
Florin Corasb636abe2021-05-04 17:08:49 -07001799 if (seq_leq (ack, tc->iss) || seq_gt (ack, tc->snd_nxt))
Florin Coras7ac053b2018-11-05 15:57:21 -08001800 {
Florin Corasb636abe2021-05-04 17:08:49 -07001801 if (!tcp_rst (tcp))
1802 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
1803 error = TCP_ERROR_RCV_WND;
Florin Coras7ac053b2018-11-05 15:57:21 -08001804 goto drop;
1805 }
1806
1807 /* Make sure ACK is valid */
Florin Corasb636abe2021-05-04 17:08:49 -07001808 if (seq_gt (tc->snd_una, ack))
Florin Coras7ac053b2018-11-05 15:57:21 -08001809 {
Florin Corasb636abe2021-05-04 17:08:49 -07001810 error = TCP_ERROR_ACK_INVALID;
Florin Coras7ac053b2018-11-05 15:57:21 -08001811 goto drop;
1812 }
1813 }
1814
1815 /*
1816 * 2. check the RST bit
1817 */
1818
Florin Corasb636abe2021-05-04 17:08:49 -07001819 if (tcp_rst (tcp))
Florin Coras7ac053b2018-11-05 15:57:21 -08001820 {
1821 /* If ACK is acceptable, signal client that peer is not
1822 * willing to accept connection and drop connection*/
Florin Corasb636abe2021-05-04 17:08:49 -07001823 if (tcp_ack (tcp))
1824 tcp_rcv_rst (wrk, tc);
1825 error = TCP_ERROR_RST_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -08001826 goto drop;
1827 }
1828
1829 /*
1830 * 3. check the security and precedence (skipped)
1831 */
1832
1833 /*
1834 * 4. check the SYN bit
1835 */
1836
1837 /* No SYN flag. Drop. */
Florin Corasb636abe2021-05-04 17:08:49 -07001838 if (!tcp_syn (tcp))
Florin Coras7ac053b2018-11-05 15:57:21 -08001839 {
Florin Corasb636abe2021-05-04 17:08:49 -07001840 error = TCP_ERROR_SEGMENT_INVALID;
Florin Coras7ac053b2018-11-05 15:57:21 -08001841 goto drop;
1842 }
1843
1844 /* Parse options */
Florin Corasb636abe2021-05-04 17:08:49 -07001845 if (tcp_options_parse (tcp, &tc->rcv_opts, 1))
Florin Coras7ac053b2018-11-05 15:57:21 -08001846 {
Florin Corasb636abe2021-05-04 17:08:49 -07001847 error = TCP_ERROR_OPTIONS;
Florin Coras7ac053b2018-11-05 15:57:21 -08001848 goto drop;
1849 }
1850
1851 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
1852 * current thread pool. */
Florin Coras57b2e4a2021-07-06 08:25:36 -07001853 new_tc = tcp_connection_alloc_w_base (thread_index, &tc);
Florin Corasb636abe2021-05-04 17:08:49 -07001854 new_tc->rcv_nxt = vnet_buffer (b[0])->tcp.seq_end;
1855 new_tc->irs = seq;
1856 new_tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
Florin Coras7ac053b2018-11-05 15:57:21 -08001857
Florin Corasb636abe2021-05-04 17:08:49 -07001858 if (tcp_opts_tstamp (&new_tc->rcv_opts))
Florin Coras7ac053b2018-11-05 15:57:21 -08001859 {
Florin Corasb636abe2021-05-04 17:08:49 -07001860 new_tc->tsval_recent = new_tc->rcv_opts.tsval;
1861 new_tc->tsval_recent_age = tcp_time_tstamp (thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -08001862 }
1863
Florin Corasb636abe2021-05-04 17:08:49 -07001864 if (tcp_opts_wscale (&new_tc->rcv_opts))
1865 new_tc->snd_wscale = new_tc->rcv_opts.wscale;
Florin Corase80b5912018-12-12 19:25:43 -08001866 else
Florin Corasb636abe2021-05-04 17:08:49 -07001867 new_tc->rcv_wscale = 0;
Florin Coras7ac053b2018-11-05 15:57:21 -08001868
Florin Corasb636abe2021-05-04 17:08:49 -07001869 new_tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
1870 << new_tc->snd_wscale;
1871 new_tc->snd_wl1 = seq;
1872 new_tc->snd_wl2 = ack;
Florin Coras7ac053b2018-11-05 15:57:21 -08001873
Florin Corasb636abe2021-05-04 17:08:49 -07001874 tcp_connection_init_vars (new_tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08001875
1876 /* SYN-ACK: See if we can switch to ESTABLISHED state */
Florin Corasb636abe2021-05-04 17:08:49 -07001877 if (PREDICT_TRUE (tcp_ack (tcp)))
Florin Coras7ac053b2018-11-05 15:57:21 -08001878 {
1879 /* Our SYN is ACKed: we have iss < ack = snd_una */
1880
1881 /* TODO Dequeue acknowledged segments if we support Fast Open */
Florin Corasb636abe2021-05-04 17:08:49 -07001882 new_tc->snd_una = ack;
1883 new_tc->state = TCP_STATE_ESTABLISHED;
Florin Coras7ac053b2018-11-05 15:57:21 -08001884
1885 /* Make sure las is initialized for the wnd computation */
Florin Corasb636abe2021-05-04 17:08:49 -07001886 new_tc->rcv_las = new_tc->rcv_nxt;
Florin Coras7ac053b2018-11-05 15:57:21 -08001887
1888 /* Notify app that we have connection. If session layer can't
1889 * allocate session send reset */
Florin Corasb636abe2021-05-04 17:08:49 -07001890 if (session_stream_connect_notify (&new_tc->connection,
Florin Coras00e01d32019-10-21 16:07:46 -07001891 SESSION_E_NONE))
Florin Coras7ac053b2018-11-05 15:57:21 -08001892 {
Florin Corasb636abe2021-05-04 17:08:49 -07001893 tcp_send_reset_w_pkt (new_tc, b[0], thread_index, is_ip4);
Florin Corasea309c42023-10-26 08:46:46 -07001894 tcp_program_cleanup (wrk, new_tc);
1895 new_tc->state = TCP_STATE_CLOSED;
1896 new_tc->c_s_index = ~0;
Florin Corasb636abe2021-05-04 17:08:49 -07001897 error = TCP_ERROR_CREATE_SESSION_FAIL;
Florin Corasd50ff7f2020-04-16 04:30:22 +00001898 goto cleanup_ho;
Florin Coras7ac053b2018-11-05 15:57:21 -08001899 }
1900
Florin Corasb636abe2021-05-04 17:08:49 -07001901 transport_fifos_init_ooo (&new_tc->connection);
1902 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08001903 /* Update rtt with the syn-ack sample */
Florin Corasb636abe2021-05-04 17:08:49 -07001904 tcp_estimate_initial_rtt (new_tc);
1905 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc);
1906 error = TCP_ERROR_SYN_ACKS_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -08001907 }
1908 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
1909 else
1910 {
Florin Corasb636abe2021-05-04 17:08:49 -07001911 new_tc->state = TCP_STATE_SYN_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -08001912
1913 /* Notify app that we have connection */
Florin Corasb636abe2021-05-04 17:08:49 -07001914 if (session_stream_connect_notify (&new_tc->connection,
Florin Coras00e01d32019-10-21 16:07:46 -07001915 SESSION_E_NONE))
Florin Coras7ac053b2018-11-05 15:57:21 -08001916 {
Florin Corasb636abe2021-05-04 17:08:49 -07001917 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
Florin Corasea309c42023-10-26 08:46:46 -07001918 tcp_program_cleanup (wrk, new_tc);
1919 new_tc->state = TCP_STATE_CLOSED;
1920 new_tc->c_s_index = ~0;
Florin Corasb636abe2021-05-04 17:08:49 -07001921 TCP_EVT (TCP_EVT_RST_SENT, tc);
1922 error = TCP_ERROR_CREATE_SESSION_FAIL;
Florin Corasd50ff7f2020-04-16 04:30:22 +00001923 goto cleanup_ho;
Florin Coras7ac053b2018-11-05 15:57:21 -08001924 }
1925
Florin Corasb636abe2021-05-04 17:08:49 -07001926 transport_fifos_init_ooo (&new_tc->connection);
1927 new_tc->tx_fifo_size = transport_tx_fifo_size (&new_tc->connection);
1928 new_tc->rtt_ts = 0;
1929 tcp_init_snd_vars (new_tc);
1930 tcp_send_synack (new_tc);
1931 error = TCP_ERROR_SYNS_RCVD;
Florin Corasd50ff7f2020-04-16 04:30:22 +00001932 goto cleanup_ho;
Florin Coras7ac053b2018-11-05 15:57:21 -08001933 }
1934
Florin Corasb636abe2021-05-04 17:08:49 -07001935 if (!(new_tc->cfg_flags & TCP_CFG_F_NO_TSO))
1936 tcp_check_tx_offload (new_tc, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08001937
Florin Coras7ac053b2018-11-05 15:57:21 -08001938 /* Read data, if any */
Florin Corasb636abe2021-05-04 17:08:49 -07001939 if (PREDICT_FALSE (vnet_buffer (b[0])->tcp.data_len))
Florin Coras7ac053b2018-11-05 15:57:21 -08001940 {
1941 clib_warning ("rcvd data in syn-sent");
Florin Corasb636abe2021-05-04 17:08:49 -07001942 error = tcp_segment_rcv (wrk, new_tc, b[0]);
1943 if (error == TCP_ERROR_ACK_OK)
1944 error = TCP_ERROR_SYN_ACKS_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -08001945 }
1946 else
1947 {
Florin Corascb711a42019-10-16 19:28:17 -07001948 /* Send ack now instead of programming it because connection was
1949 * just established and it's not optional. */
Florin Corasb636abe2021-05-04 17:08:49 -07001950 tcp_send_ack (new_tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08001951 }
1952
Florin Corasd50ff7f2020-04-16 04:30:22 +00001953 cleanup_ho:
1954
1955 /* If this is not the owning thread, wait for syn retransmit to
1956 * expire and cleanup then */
Florin Corasb636abe2021-05-04 17:08:49 -07001957 if (tcp_half_open_connection_cleanup (tc))
1958 tc->flags |= TCP_CONN_HALF_OPEN_DONE;
Florin Corasd50ff7f2020-04-16 04:30:22 +00001959
Florin Coras7ac053b2018-11-05 15:57:21 -08001960 drop:
1961
Florin Corasb636abe2021-05-04 17:08:49 -07001962 b += 1;
1963 n_left_from -= 1;
1964 tcp_inc_counter (syn_sent, error, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -05001965 }
1966
Florin Coras0242d302022-12-22 15:03:44 -08001967 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
Florin Corasb636abe2021-05-04 17:08:49 -07001968 vlib_buffer_free (vm, from, frame->n_vectors);
Florin Coras6939d5e2020-02-10 23:22:34 +00001969 tcp_handle_disconnects (wrk);
Florin Coras7ac053b2018-11-05 15:57:21 -08001970
Florin Corasb636abe2021-05-04 17:08:49 -07001971 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05001972}
1973
Filip Tehlare275bed2019-03-06 00:06:56 -08001974VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
1975 vlib_node_runtime_t * node,
1976 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05001977{
1978 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1979}
1980
Filip Tehlare275bed2019-03-06 00:06:56 -08001981VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
1982 vlib_node_runtime_t * node,
1983 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05001984{
1985 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1986}
1987
1988/* *INDENT-OFF* */
1989VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
1990{
Dave Barach68b0fb02017-02-28 15:15:56 -05001991 .name = "tcp4-syn-sent",
1992 /* Takes a vector of packets. */
1993 .vector_size = sizeof (u32),
1994 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00001995 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02001996 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05001997};
1998/* *INDENT-ON* */
1999
Dave Barach68b0fb02017-02-28 15:15:56 -05002000/* *INDENT-OFF* */
2001VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2002{
Dave Barach68b0fb02017-02-28 15:15:56 -05002003 .name = "tcp6-syn-sent",
2004 /* Takes a vector of packets. */
2005 .vector_size = sizeof (u32),
2006 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002007 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02002008 .format_trace = format_tcp_rx_trace_short,
2009};
Dave Barach68b0fb02017-02-28 15:15:56 -05002010/* *INDENT-ON* */
2011
Florin Coras95929092021-05-04 19:30:58 -07002012static void
2013tcp46_rcv_process_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2014 u32 *from, u32 n_bufs)
2015{
2016 u32 thread_index = vm->thread_index;
2017 tcp_connection_t *tc = 0;
2018 tcp_rx_trace_t *t;
2019 vlib_buffer_t *b;
2020 int i;
2021
2022 for (i = 0; i < n_bufs; i++)
2023 {
2024 b = vlib_get_buffer (vm, from[i]);
2025 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2026 continue;
2027 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2028 thread_index);
2029 t = vlib_add_trace (vm, node, b, sizeof (*t));
2030 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2031 }
2032}
2033
Dave Barach68b0fb02017-02-28 15:15:56 -05002034/**
Florin Corasd79b41e2017-03-04 05:37:52 -08002035 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
Dave Barach68b0fb02017-02-28 15:15:56 -05002036 * as per RFC793 p. 64
2037 */
2038always_inline uword
Florin Coras95929092021-05-04 19:30:58 -07002039tcp46_rcv_process_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2040 vlib_frame_t *frame, int is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05002041{
Florin Coras0242d302022-12-22 15:03:44 -08002042 u32 thread_index = vm->thread_index, n_left_from, *from, max_deq;
Florin Coras7ac053b2018-11-05 15:57:21 -08002043 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
Florin Coras95929092021-05-04 19:30:58 -07002044 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
Dave Barach68b0fb02017-02-28 15:15:56 -05002045
Florin Coras95929092021-05-04 19:30:58 -07002046 from = vlib_frame_vector_args (frame);
2047 n_left_from = frame->n_vectors;
2048
2049 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2050 tcp46_rcv_process_trace_frame (vm, node, from, n_left_from);
2051
2052 vlib_get_buffers (vm, from, bufs, n_left_from);
2053 b = bufs;
Dave Barach68b0fb02017-02-28 15:15:56 -05002054
2055 while (n_left_from > 0)
2056 {
Florin Coras95929092021-05-04 19:30:58 -07002057 u32 error = TCP_ERROR_NONE;
2058 tcp_header_t *tcp = 0;
2059 tcp_connection_t *tc;
2060 u8 is_fin;
Dave Barach68b0fb02017-02-28 15:15:56 -05002061
Florin Coras95929092021-05-04 19:30:58 -07002062 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2063 thread_index);
2064 if (PREDICT_FALSE (tc == 0))
Dave Barach68b0fb02017-02-28 15:15:56 -05002065 {
Florin Coras95929092021-05-04 19:30:58 -07002066 error = TCP_ERROR_INVALID_CONNECTION;
Florin Coras7ac053b2018-11-05 15:57:21 -08002067 goto drop;
Dave Barach68b0fb02017-02-28 15:15:56 -05002068 }
2069
Florin Coras95929092021-05-04 19:30:58 -07002070 tcp = tcp_buffer_hdr (b[0]);
2071 is_fin = tcp_is_fin (tcp);
Florin Coras7ac053b2018-11-05 15:57:21 -08002072
Florin Coras7ac053b2018-11-05 15:57:21 -08002073 if (CLIB_DEBUG)
2074 {
Florin Coras95929092021-05-04 19:30:58 -07002075 if (!(tc->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
Florin Coras7ac053b2018-11-05 15:57:21 -08002076 {
Ryujiro Shibuyac8be8512019-10-28 00:32:12 +00002077 tcp_connection_t *tmp;
Florin Coras95929092021-05-04 19:30:58 -07002078 tmp = tcp_lookup_connection (tc->c_fib_index, b[0], thread_index,
Ryujiro Shibuyac8be8512019-10-28 00:32:12 +00002079 is_ip4);
Florin Coras95929092021-05-04 19:30:58 -07002080 if (tmp->state != tc->state)
Ryujiro Shibuyac8be8512019-10-28 00:32:12 +00002081 {
Florin Coras95929092021-05-04 19:30:58 -07002082 if (tc->state != TCP_STATE_CLOSED)
Ryujiro Shibuyac8be8512019-10-28 00:32:12 +00002083 clib_warning ("state changed");
2084 goto drop;
2085 }
Florin Coras7ac053b2018-11-05 15:57:21 -08002086 }
2087 }
2088
2089 /*
2090 * Special treatment for CLOSED
2091 */
Florin Coras95929092021-05-04 19:30:58 -07002092 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
Florin Coras7ac053b2018-11-05 15:57:21 -08002093 {
Florin Coras95929092021-05-04 19:30:58 -07002094 error = TCP_ERROR_CONNECTION_CLOSED;
Florin Coras7ac053b2018-11-05 15:57:21 -08002095 goto drop;
2096 }
2097
2098 /*
2099 * For all other states (except LISTEN)
2100 */
2101
2102 /* 1-4: check SEQ, RST, SYN */
Florin Coras95929092021-05-04 19:30:58 -07002103 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc, b[0], tcp, &error)))
Florin Coras7ac053b2018-11-05 15:57:21 -08002104 goto drop;
2105
2106 /* 5: check the ACK field */
Florin Coras95929092021-05-04 19:30:58 -07002107 switch (tc->state)
Florin Coras7ac053b2018-11-05 15:57:21 -08002108 {
2109 case TCP_STATE_SYN_RCVD:
2110 /*
2111 * If the segment acknowledgment is not acceptable, form a
2112 * reset segment,
2113 * <SEQ=SEG.ACK><CTL=RST>
2114 * and send it.
2115 */
Florin Coras95929092021-05-04 19:30:58 -07002116 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
Florin Coras7ac053b2018-11-05 15:57:21 -08002117 {
Florin Coras95929092021-05-04 19:30:58 -07002118 tcp_send_reset_w_pkt (tc, b[0], thread_index, is_ip4);
2119 error = TCP_ERROR_SEGMENT_INVALID;
Florin Coras4850e3e2018-12-12 14:34:38 -08002120 goto drop;
2121 }
2122
Florin Corasda2ae9a2023-10-14 15:16:18 -07002123 /* Avoid notifying app if connection is about to be closed */
2124 if (PREDICT_FALSE (is_fin))
2125 break;
2126
Florin Coras7ac053b2018-11-05 15:57:21 -08002127 /* Update rtt and rto */
Florin Coras95929092021-05-04 19:30:58 -07002128 tcp_estimate_initial_rtt (tc);
2129 tcp_connection_tx_pacer_update (tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08002130
2131 /* Switch state to ESTABLISHED */
Florin Coras95929092021-05-04 19:30:58 -07002132 tc->state = TCP_STATE_ESTABLISHED;
2133 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08002134
Florin Coras95929092021-05-04 19:30:58 -07002135 if (!(tc->cfg_flags & TCP_CFG_F_NO_TSO))
2136 tcp_check_tx_offload (tc, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002137
Florin Coras7ac053b2018-11-05 15:57:21 -08002138 /* Initialize session variables */
Florin Coras95929092021-05-04 19:30:58 -07002139 tc->snd_una = vnet_buffer (b[0])->tcp.ack_number;
2140 tc->snd_wnd = clib_net_to_host_u16 (tcp->window)
2141 << tc->rcv_opts.wscale;
2142 tc->snd_wl1 = vnet_buffer (b[0])->tcp.seq_number;
2143 tc->snd_wl2 = vnet_buffer (b[0])->tcp.ack_number;
Florin Coras7ac053b2018-11-05 15:57:21 -08002144
2145 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
Florin Coras95929092021-05-04 19:30:58 -07002146 tcp_retransmit_timer_reset (&wrk->timer_wheel, tc);
2147 if (session_stream_accept_notify (&tc->connection))
Florin Corasa9d5bea2018-12-17 08:24:19 -08002148 {
Florin Coras95929092021-05-04 19:30:58 -07002149 error = TCP_ERROR_MSG_QUEUE_FULL;
2150 tcp_send_reset (tc);
2151 session_transport_delete_notify (&tc->connection);
2152 tcp_connection_cleanup (tc);
Florin Corasa9d5bea2018-12-17 08:24:19 -08002153 goto drop;
2154 }
Florin Coras95929092021-05-04 19:30:58 -07002155 error = TCP_ERROR_ACK_OK;
Florin Coras7ac053b2018-11-05 15:57:21 -08002156 break;
2157 case TCP_STATE_ESTABLISHED:
2158 /* We can get packets in established state here because they
2159 * were enqueued before state change */
Florin Coras95929092021-05-04 19:30:58 -07002160 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
Florin Coras7ac053b2018-11-05 15:57:21 -08002161 goto drop;
2162
2163 break;
2164 case TCP_STATE_FIN_WAIT_1:
2165 /* In addition to the processing for the ESTABLISHED state, if
2166 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2167 * continue processing in that state. */
Florin Coras95929092021-05-04 19:30:58 -07002168 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
Florin Coras7ac053b2018-11-05 15:57:21 -08002169 goto drop;
2170
2171 /* Still have to send the FIN */
Florin Coras95929092021-05-04 19:30:58 -07002172 if (tc->flags & TCP_CONN_FINPNDG)
Florin Coras7ac053b2018-11-05 15:57:21 -08002173 {
2174 /* TX fifo finally drained */
Florin Coras95929092021-05-04 19:30:58 -07002175 max_deq = transport_max_tx_dequeue (&tc->connection);
2176 if (max_deq <= tc->burst_acked)
2177 tcp_send_fin (tc);
Florin Coras070fd4b2019-04-02 19:03:23 -07002178 /* If a fin was received and data was acked extend wait */
Florin Coras95929092021-05-04 19:30:58 -07002179 else if ((tc->flags & TCP_CONN_FINRCVD) && tc->bytes_acked)
2180 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras9094b5c2019-08-12 14:17:47 -07002181 tcp_cfg.closewait_time);
Florin Coras7ac053b2018-11-05 15:57:21 -08002182 }
2183 /* If FIN is ACKed */
Florin Coras95929092021-05-04 19:30:58 -07002184 else if (tc->snd_una == tc->snd_nxt)
Florin Coras7ac053b2018-11-05 15:57:21 -08002185 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002186 /* Stop all retransmit timers because we have nothing more
Florin Corasf65074e2019-03-31 17:17:11 -07002187 * to send. */
Florin Coras95929092021-05-04 19:30:58 -07002188 tcp_connection_timers_reset (tc);
Florin Corasf65074e2019-03-31 17:17:11 -07002189
2190 /* We already have a FIN but didn't transition to CLOSING
2191 * because of outstanding tx data. Close the connection. */
Florin Coras95929092021-05-04 19:30:58 -07002192 if (tc->flags & TCP_CONN_FINRCVD)
Florin Corasf65074e2019-03-31 17:17:11 -07002193 {
Florin Coras95929092021-05-04 19:30:58 -07002194 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2195 session_transport_closed_notify (&tc->connection);
2196 tcp_program_cleanup (wrk, tc);
Florin Corasf65074e2019-03-31 17:17:11 -07002197 goto drop;
2198 }
2199
Florin Coras95929092021-05-04 19:30:58 -07002200 tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_2);
Florin Corasf65074e2019-03-31 17:17:11 -07002201 /* Enable waitclose because we're willing to wait for peer's
2202 * FIN but not indefinitely. */
Florin Coras95929092021-05-04 19:30:58 -07002203 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002204 tcp_cfg.finwait2_time);
Florin Corasefefc6b2018-11-07 12:49:19 -08002205
2206 /* Don't try to deq the FIN acked */
Florin Coras95929092021-05-04 19:30:58 -07002207 if (tc->burst_acked > 1)
2208 session_tx_fifo_dequeue_drop (&tc->connection,
2209 tc->burst_acked - 1);
2210 tc->burst_acked = 0;
Florin Coras7ac053b2018-11-05 15:57:21 -08002211 }
2212 break;
2213 case TCP_STATE_FIN_WAIT_2:
2214 /* In addition to the processing for the ESTABLISHED state, if
2215 * the retransmission queue is empty, the user's CLOSE can be
2216 * acknowledged ("ok") but do not delete the TCB. */
Florin Coras95929092021-05-04 19:30:58 -07002217 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
Florin Coras7ac053b2018-11-05 15:57:21 -08002218 goto drop;
Florin Coras95929092021-05-04 19:30:58 -07002219 tc->burst_acked = 0;
Florin Coras7ac053b2018-11-05 15:57:21 -08002220 break;
2221 case TCP_STATE_CLOSE_WAIT:
2222 /* Do the same processing as for the ESTABLISHED state. */
Florin Coras95929092021-05-04 19:30:58 -07002223 if (tcp_rcv_ack (wrk, tc, b[0], tcp, &error))
Florin Coras7ac053b2018-11-05 15:57:21 -08002224 goto drop;
2225
Florin Coras95929092021-05-04 19:30:58 -07002226 if (!(tc->flags & TCP_CONN_FINPNDG))
Florin Corasf65074e2019-03-31 17:17:11 -07002227 break;
2228
2229 /* Still have outstanding tx data */
Florin Coras95929092021-05-04 19:30:58 -07002230 max_deq = transport_max_tx_dequeue (&tc->connection);
2231 if (max_deq > tc->burst_acked)
Florin Corasf65074e2019-03-31 17:17:11 -07002232 break;
2233
Florin Coras95929092021-05-04 19:30:58 -07002234 tcp_send_fin (tc);
2235 tcp_connection_timers_reset (tc);
2236 tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
2237 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002238 tcp_cfg.lastack_time);
Florin Coras7ac053b2018-11-05 15:57:21 -08002239 break;
2240 case TCP_STATE_CLOSING:
2241 /* In addition to the processing for the ESTABLISHED state, if
2242 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2243 * otherwise ignore the segment. */
Florin Coras95929092021-05-04 19:30:58 -07002244 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
Florin Corasf65074e2019-03-31 17:17:11 -07002245 goto drop;
Florin Coras47596832019-03-12 18:58:54 -07002246
Florin Coras95929092021-05-04 19:30:58 -07002247 if (tc->snd_una != tc->snd_nxt)
Florin Corasf65074e2019-03-31 17:17:11 -07002248 goto drop;
Florin Coras7ac053b2018-11-05 15:57:21 -08002249
Florin Coras95929092021-05-04 19:30:58 -07002250 tcp_connection_timers_reset (tc);
2251 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2252 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002253 tcp_cfg.timewait_time);
Florin Coras95929092021-05-04 19:30:58 -07002254 session_transport_closed_notify (&tc->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08002255 goto drop;
2256
2257 break;
2258 case TCP_STATE_LAST_ACK:
2259 /* The only thing that [should] arrive in this state is an
2260 * acknowledgment of our FIN. If our FIN is now acknowledged,
2261 * delete the TCB, enter the CLOSED state, and return. */
2262
Florin Coras95929092021-05-04 19:30:58 -07002263 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
Florin Corasf65074e2019-03-31 17:17:11 -07002264 goto drop;
2265
Florin Coras7ac053b2018-11-05 15:57:21 -08002266 /* Apparently our ACK for the peer's FIN was lost */
Florin Coras95929092021-05-04 19:30:58 -07002267 if (is_fin && tc->snd_una != tc->snd_nxt)
Florin Coras7ac053b2018-11-05 15:57:21 -08002268 {
Florin Coras95929092021-05-04 19:30:58 -07002269 tcp_send_fin (tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08002270 goto drop;
2271 }
2272
Florin Coras95929092021-05-04 19:30:58 -07002273 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
2274 session_transport_closed_notify (&tc->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08002275
2276 /* Don't free the connection from the data path since
2277 * we can't ensure that we have no packets already enqueued
2278 * to output. Rely instead on the waitclose timer */
Florin Coras95929092021-05-04 19:30:58 -07002279 tcp_connection_timers_reset (tc);
2280 tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08002281
2282 goto drop;
2283
2284 break;
2285 case TCP_STATE_TIME_WAIT:
2286 /* The only thing that can arrive in this state is a
2287 * retransmission of the remote FIN. Acknowledge it, and restart
2288 * the 2 MSL timeout. */
2289
Florin Coras95929092021-05-04 19:30:58 -07002290 if (tcp_rcv_ack_no_cc (tc, b[0], &error))
Florin Coras7ac053b2018-11-05 15:57:21 -08002291 goto drop;
2292
Florin Coras95929092021-05-04 19:30:58 -07002293 if (!is_fin)
Florin Coras37db4302019-03-13 13:25:57 -07002294 goto drop;
2295
Florin Coras95929092021-05-04 19:30:58 -07002296 tcp_program_ack (tc);
2297 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002298 tcp_cfg.timewait_time);
Florin Coras7ac053b2018-11-05 15:57:21 -08002299 goto drop;
2300
2301 break;
2302 default:
2303 ASSERT (0);
2304 }
2305
2306 /* 6: check the URG bit TODO */
2307
2308 /* 7: process the segment text */
Florin Coras95929092021-05-04 19:30:58 -07002309 switch (tc->state)
Florin Coras7ac053b2018-11-05 15:57:21 -08002310 {
2311 case TCP_STATE_ESTABLISHED:
2312 case TCP_STATE_FIN_WAIT_1:
2313 case TCP_STATE_FIN_WAIT_2:
Florin Coras95929092021-05-04 19:30:58 -07002314 if (vnet_buffer (b[0])->tcp.data_len)
2315 error = tcp_segment_rcv (wrk, tc, b[0]);
Florin Corasc67724a2020-11-06 14:21:26 -08002316 /* Don't accept out of order fins lower */
Florin Coras95929092021-05-04 19:30:58 -07002317 if (vnet_buffer (b[0])->tcp.seq_end != tc->rcv_nxt)
Florin Corasc67724a2020-11-06 14:21:26 -08002318 goto drop;
Florin Coras7ac053b2018-11-05 15:57:21 -08002319 break;
2320 case TCP_STATE_CLOSE_WAIT:
2321 case TCP_STATE_CLOSING:
2322 case TCP_STATE_LAST_ACK:
2323 case TCP_STATE_TIME_WAIT:
2324 /* This should not occur, since a FIN has been received from the
2325 * remote side. Ignore the segment text. */
2326 break;
2327 }
2328
2329 /* 8: check the FIN bit */
Florin Coras95929092021-05-04 19:30:58 -07002330 if (!is_fin)
Florin Coras7ac053b2018-11-05 15:57:21 -08002331 goto drop;
2332
Florin Coras95929092021-05-04 19:30:58 -07002333 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
Florin Coras3c514d52018-12-22 11:39:33 -08002334
Florin Coras95929092021-05-04 19:30:58 -07002335 switch (tc->state)
Florin Coras7ac053b2018-11-05 15:57:21 -08002336 {
2337 case TCP_STATE_ESTABLISHED:
Florin Coras3c514d52018-12-22 11:39:33 -08002338 /* Account for the FIN and send ack */
Florin Coras95929092021-05-04 19:30:58 -07002339 tc->rcv_nxt += 1;
2340 tcp_program_ack (tc);
2341 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
2342 tcp_program_disconnect (wrk, tc);
2343 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002344 tcp_cfg.closewait_time);
Florin Coras5c0f1662018-12-19 01:38:57 -08002345 break;
Florin Coras7ac053b2018-11-05 15:57:21 -08002346 case TCP_STATE_SYN_RCVD:
Florin Corasda2ae9a2023-10-14 15:16:18 -07002347 /* Send FIN-ACK and enter TIME-WAIT, as opposed to LAST-ACK,
2348 * because the app was not notified yet and we want to avoid
2349 * session state transitions to ensure cleanup does not
2350 * propagate to app. */
Florin Coras95929092021-05-04 19:30:58 -07002351 tcp_connection_timers_reset (tc);
2352 tc->rcv_nxt += 1;
2353 tcp_send_fin (tc);
Florin Corasda2ae9a2023-10-14 15:16:18 -07002354 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2355 tcp_program_cleanup (wrk, tc);
Florin Coras7ac053b2018-11-05 15:57:21 -08002356 break;
2357 case TCP_STATE_CLOSE_WAIT:
2358 case TCP_STATE_CLOSING:
2359 case TCP_STATE_LAST_ACK:
2360 /* move along .. */
2361 break;
2362 case TCP_STATE_FIN_WAIT_1:
Florin Coras95929092021-05-04 19:30:58 -07002363 tc->rcv_nxt += 1;
Florin Coras070fd4b2019-04-02 19:03:23 -07002364
Florin Coras95929092021-05-04 19:30:58 -07002365 if (tc->flags & TCP_CONN_FINPNDG)
Florin Coras565115e2019-02-20 19:48:31 -08002366 {
Florin Coras070fd4b2019-04-02 19:03:23 -07002367 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2368 * sending it. Since we already received a fin, do not wait
2369 * for too long. */
Florin Coras95929092021-05-04 19:30:58 -07002370 tc->flags |= TCP_CONN_FINRCVD;
2371 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras9094b5c2019-08-12 14:17:47 -07002372 tcp_cfg.closewait_time);
Florin Coras565115e2019-02-20 19:48:31 -08002373 }
2374 else
Florin Corasf65074e2019-03-31 17:17:11 -07002375 {
Florin Coras95929092021-05-04 19:30:58 -07002376 tcp_connection_set_state (tc, TCP_STATE_CLOSING);
2377 tcp_program_ack (tc);
Florin Coras070fd4b2019-04-02 19:03:23 -07002378 /* Wait for ACK for our FIN but not forever */
Florin Coras95929092021-05-04 19:30:58 -07002379 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras9094b5c2019-08-12 14:17:47 -07002380 tcp_cfg.closing_time);
Florin Corasf65074e2019-03-31 17:17:11 -07002381 }
Florin Coras7ac053b2018-11-05 15:57:21 -08002382 break;
2383 case TCP_STATE_FIN_WAIT_2:
2384 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
Florin Coras95929092021-05-04 19:30:58 -07002385 tc->rcv_nxt += 1;
2386 tcp_connection_set_state (tc, TCP_STATE_TIME_WAIT);
2387 tcp_connection_timers_reset (tc);
2388 tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002389 tcp_cfg.timewait_time);
Florin Coras95929092021-05-04 19:30:58 -07002390 tcp_program_ack (tc);
2391 session_transport_closed_notify (&tc->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08002392 break;
2393 case TCP_STATE_TIME_WAIT:
2394 /* Remain in the TIME-WAIT state. Restart the time-wait
2395 * timeout.
2396 */
Florin Coras95929092021-05-04 19:30:58 -07002397 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
Florin Coras0765d972020-03-18 21:26:41 +00002398 tcp_cfg.timewait_time);
Florin Coras7ac053b2018-11-05 15:57:21 -08002399 break;
2400 }
Florin Coras95929092021-05-04 19:30:58 -07002401 error = TCP_ERROR_FIN_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -08002402
2403 drop:
2404
Florin Coras95929092021-05-04 19:30:58 -07002405 b += 1;
2406 n_left_from -= 1;
2407 tcp_inc_counter (rcv_process, error, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -05002408 }
2409
Florin Coras0242d302022-12-22 15:03:44 -08002410 session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP, thread_index);
Florin Coras9ece3c02018-11-05 11:06:53 -08002411 tcp_handle_postponed_dequeues (wrk);
Florin Coras79fdfd62019-05-23 06:19:09 -07002412 tcp_handle_disconnects (wrk);
Florin Coras95929092021-05-04 19:30:58 -07002413 vlib_buffer_free (vm, from, frame->n_vectors);
Florin Coras7ac053b2018-11-05 15:57:21 -08002414
Florin Coras95929092021-05-04 19:30:58 -07002415 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002416}
2417
Filip Tehlare275bed2019-03-06 00:06:56 -08002418VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2419 vlib_node_runtime_t * node,
2420 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002421{
2422 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2423}
2424
Filip Tehlare275bed2019-03-06 00:06:56 -08002425VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2426 vlib_node_runtime_t * node,
2427 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002428{
2429 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2430}
2431
2432/* *INDENT-OFF* */
Florin Coras9a1fbb52023-06-08 20:47:11 -07002433VLIB_REGISTER_NODE (tcp4_rcv_process_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002434 .name = "tcp4-rcv-process",
2435 /* Takes a vector of packets. */
2436 .vector_size = sizeof (u32),
2437 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002438 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02002439 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002440};
2441/* *INDENT-ON* */
2442
Dave Barach68b0fb02017-02-28 15:15:56 -05002443/* *INDENT-OFF* */
Florin Coras9a1fbb52023-06-08 20:47:11 -07002444VLIB_REGISTER_NODE (tcp6_rcv_process_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002445 .name = "tcp6-rcv-process",
2446 /* Takes a vector of packets. */
2447 .vector_size = sizeof (u32),
2448 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002449 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02002450 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002451};
2452/* *INDENT-ON* */
2453
Florin Coras7f969c72021-05-04 14:53:25 -07002454static void
2455tcp46_listen_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2456 u32 *to_next, u32 n_bufs)
2457{
2458 tcp_connection_t *tc = 0;
2459 tcp_rx_trace_t *t;
2460 vlib_buffer_t *b;
2461 int i;
2462
2463 for (i = 0; i < n_bufs; i++)
2464 {
2465 b = vlib_get_buffer (vm, to_next[i]);
2466 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2467 continue;
2468 if (vnet_buffer (b)->tcp.flags == TCP_STATE_LISTEN)
2469 tc = tcp_listener_get (vnet_buffer (b)->tcp.connection_index);
2470 t = vlib_add_trace (vm, node, b, sizeof (*t));
2471 tcp_set_rx_trace_data (t, tc, tcp_buffer_hdr (b), b, 1);
2472 }
2473}
2474
Dave Barach68b0fb02017-02-28 15:15:56 -05002475/**
Michal Kalderon3effadc2021-08-08 04:30:39 -07002476 * SYN received in TIME-WAIT state.
2477 *
2478 * RFC 1122:
2479 * "When a connection is [...] on TIME-WAIT state [...]
2480 * [a TCP] MAY accept a new SYN from the remote TCP to
2481 * reopen the connection directly, if it:
2482 *
2483 * (1) assigns its initial sequence number for the new
2484 * connection to be larger than the largest sequence
2485 * number it used on the previous connection incarnation,
2486 * and
2487 *
2488 * (2) returns to TIME-WAIT state if the SYN turns out
2489 * to be an old duplicate".
2490 *
2491 * The function returns true if the syn can be accepted during
2492 * connection time-wait (port reuse). In this case the function
2493 * also calculates what the iss should be for the new connection.
2494 */
2495always_inline int
2496syn_during_timewait (tcp_connection_t *tc, vlib_buffer_t *b, u32 *iss)
2497{
2498 int paws_reject = tcp_segment_check_paws (tc);
2499 u32 tw_iss;
2500
2501 *iss = 0;
2502 /* Check that the SYN arrived out of window. We accept it */
2503 if (!paws_reject &&
2504 (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt) ||
2505 (tcp_opts_tstamp (&tc->rcv_opts) &&
2506 timestamp_lt (tc->tsval_recent, tc->rcv_opts.tsval))))
2507 {
2508 /* Set the iss of the new connection to be the largest sequence number
2509 * the old peer would have accepted and add some random number
2510 */
2511 tw_iss = tc->snd_nxt + tcp_available_snd_wnd (tc) +
2512 (uword) (tcp_time_now_us (tc->c_thread_index) * 1e6) % 65535;
2513 if (tw_iss == 0)
2514 tw_iss++;
2515 *iss = tw_iss;
2516
2517 return 1;
2518 }
2519 else
2520 {
2521 TCP_DBG (
2522 "ERROR not accepting SYN in timewait,paws_reject=%d, seq_num =%ld, "
2523 "rcv_nxt=%ld, tstamp_present=%d, tsval_recent = %d, tsval = %d\n",
2524 paws_reject, vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt,
2525 tcp_opts_tstamp (&tc->rcv_opts), tc->tsval_recent, tc->rcv_opts.tsval);
2526 return 0;
2527 }
2528}
2529
2530/**
Dave Barach68b0fb02017-02-28 15:15:56 -05002531 * LISTEN state processing as per RFC 793 p. 65
2532 */
2533always_inline uword
Florin Coras7f969c72021-05-04 14:53:25 -07002534tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2535 vlib_frame_t *frame, int is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05002536{
Florin Coras7f969c72021-05-04 14:53:25 -07002537 u32 n_left_from, *from, n_syns = 0;
2538 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
Florin Coras27bb99e2020-03-17 17:09:12 +00002539 u32 thread_index = vm->thread_index;
Michal Kalderon3effadc2021-08-08 04:30:39 -07002540 u32 tw_iss = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002541
Florin Coras7f969c72021-05-04 14:53:25 -07002542 from = vlib_frame_vector_args (frame);
2543 n_left_from = frame->n_vectors;
2544
2545 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2546 tcp46_listen_trace_frame (vm, node, from, n_left_from);
2547
2548 vlib_get_buffers (vm, from, bufs, n_left_from);
2549 b = bufs;
Dave Barach68b0fb02017-02-28 15:15:56 -05002550
Dave Barach68b0fb02017-02-28 15:15:56 -05002551 while (n_left_from > 0)
2552 {
Florin Coras27bb99e2020-03-17 17:09:12 +00002553 tcp_connection_t *lc, *child;
Florin Corasde7fcac2020-01-16 04:04:54 +00002554
Florin Corasee1cb462020-12-29 09:42:58 -08002555 /* Flags initialized with connection state after lookup */
Florin Coras7f969c72021-05-04 14:53:25 -07002556 if (vnet_buffer (b[0])->tcp.flags == TCP_STATE_LISTEN)
Florin Corasee1cb462020-12-29 09:42:58 -08002557 {
Florin Coras7f969c72021-05-04 14:53:25 -07002558 lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
Florin Corasee1cb462020-12-29 09:42:58 -08002559 }
Florin Coras3ffc77d2023-02-16 18:59:38 -08002560 /* Probably we are in time-wait or closed state */
2561 else
Florin Corasde7fcac2020-01-16 04:04:54 +00002562 {
Florin Coras27bb99e2020-03-17 17:09:12 +00002563 tcp_connection_t *tc;
Florin Coras7f969c72021-05-04 14:53:25 -07002564 tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
Florin Coras27bb99e2020-03-17 17:09:12 +00002565 thread_index);
2566 if (tc->state != TCP_STATE_TIME_WAIT)
Florin Corasb7f035f2019-12-27 09:27:52 -08002567 {
Florin Corase8d67712022-03-15 21:46:34 -07002568 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
Florin Coras27bb99e2020-03-17 17:09:12 +00002569 goto done;
Florin Corasb7f035f2019-12-27 09:27:52 -08002570 }
Michal Kalderon3effadc2021-08-08 04:30:39 -07002571
2572 if (PREDICT_FALSE (!syn_during_timewait (tc, b[0], &tw_iss)))
2573 {
2574 /* This SYN can't be accepted */
Florin Corase8d67712022-03-15 21:46:34 -07002575 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
Michal Kalderon3effadc2021-08-08 04:30:39 -07002576 goto done;
2577 }
2578
Florin Coras7f969c72021-05-04 14:53:25 -07002579 lc = tcp_lookup_listener (b[0], tc->c_fib_index, is_ip4);
Florin Corasb7f035f2019-12-27 09:27:52 -08002580 /* clean up the old session */
Florin Coras27bb99e2020-03-17 17:09:12 +00002581 tcp_connection_del (tc);
Florin Coras355791c2020-10-11 11:20:56 -07002582 /* listener was cleaned up */
2583 if (!lc)
2584 {
Florin Corase8d67712022-03-15 21:46:34 -07002585 tcp_inc_counter (listen, TCP_ERROR_NO_LISTENER, 1);
Florin Coras355791c2020-10-11 11:20:56 -07002586 goto done;
2587 }
Florin Coras27bb99e2020-03-17 17:09:12 +00002588 }
2589
2590 /* Make sure connection wasn't just created */
Florin Coras7f969c72021-05-04 14:53:25 -07002591 child =
2592 tcp_lookup_connection (lc->c_fib_index, b[0], thread_index, is_ip4);
Florin Coras27bb99e2020-03-17 17:09:12 +00002593 if (PREDICT_FALSE (child->state != TCP_STATE_LISTEN))
2594 {
Florin Corase8d67712022-03-15 21:46:34 -07002595 tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
Florin Coras27bb99e2020-03-17 17:09:12 +00002596 goto done;
Yu Pingb092b772019-12-27 04:04:33 +08002597 }
Florin Coras7ac053b2018-11-05 15:57:21 -08002598
Florin Coras7ac053b2018-11-05 15:57:21 -08002599 /* Create child session. For syn-flood protection use filter */
2600
Florin Coras7f969c72021-05-04 14:53:25 -07002601 /* 1. first check for an RST: handled by input dispatch */
Florin Coras7ac053b2018-11-05 15:57:21 -08002602
Florin Coras7f969c72021-05-04 14:53:25 -07002603 /* 2. second check for an ACK: handled by input dispatch */
Florin Coras7ac053b2018-11-05 15:57:21 -08002604
2605 /* 3. check for a SYN (did that already) */
2606
Florin Coras7ac053b2018-11-05 15:57:21 -08002607 /* Create child session and send SYN-ACK */
Florin Coras27bb99e2020-03-17 17:09:12 +00002608 child = tcp_connection_alloc (thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -08002609
Florin Coras7f969c72021-05-04 14:53:25 -07002610 if (tcp_options_parse (tcp_buffer_hdr (b[0]), &child->rcv_opts, 1))
Florin Coras7ac053b2018-11-05 15:57:21 -08002611 {
Florin Corase8d67712022-03-15 21:46:34 -07002612 tcp_inc_counter (listen, TCP_ERROR_OPTIONS, 1);
Florin Coras27bb99e2020-03-17 17:09:12 +00002613 tcp_connection_free (child);
2614 goto done;
Florin Coras7ac053b2018-11-05 15:57:21 -08002615 }
2616
Florin Coras7f969c72021-05-04 14:53:25 -07002617 tcp_init_w_buffer (child, b[0], is_ip4);
Florin Coras27bb99e2020-03-17 17:09:12 +00002618
2619 child->state = TCP_STATE_SYN_RCVD;
2620 child->c_fib_index = lc->c_fib_index;
2621 child->cc_algo = lc->cc_algo;
Michal Kalderon3effadc2021-08-08 04:30:39 -07002622
2623 /* In the regular case, the tw_iss will be zero, but
2624 * in the special case of syn arriving in time_wait state, the value
2625 * will be set according to rfc 1122
2626 */
2627 child->iss = tw_iss;
Florin Coras27bb99e2020-03-17 17:09:12 +00002628 tcp_connection_init_vars (child);
2629 child->rto = TCP_RTO_MIN;
2630
Ivan Shvedunov9fefa892020-07-27 19:59:38 +03002631 /*
2632 * This initializes elog track, must be done before synack.
2633 * We also do it before possible tcp_connection_cleanup() as it
2634 * generates TCP_EVT_DELETE event.
2635 */
2636 TCP_EVT (TCP_EVT_SYN_RCVD, child, 1);
2637
Florin Coras27bb99e2020-03-17 17:09:12 +00002638 if (session_stream_accept (&child->connection, lc->c_s_index,
2639 lc->c_thread_index, 0 /* notify */ ))
Florin Coras7ac053b2018-11-05 15:57:21 -08002640 {
Florin Coras27bb99e2020-03-17 17:09:12 +00002641 tcp_connection_cleanup (child);
Florin Corase8d67712022-03-15 21:46:34 -07002642 tcp_inc_counter (listen, TCP_ERROR_CREATE_SESSION_FAIL, 1);
Florin Coras27bb99e2020-03-17 17:09:12 +00002643 goto done;
Florin Coras7ac053b2018-11-05 15:57:21 -08002644 }
2645
Florin Coras8c4fa012020-11-06 16:59:08 -08002646 transport_fifos_init_ooo (&child->connection);
Florin Coras27bb99e2020-03-17 17:09:12 +00002647 child->tx_fifo_size = transport_tx_fifo_size (&child->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08002648
Florin Corasd2f51742020-07-24 09:49:46 -07002649 tcp_send_synack (child);
Florin Corase8d67712022-03-15 21:46:34 -07002650 n_syns += 1;
Florin Corasd2f51742020-07-24 09:49:46 -07002651
Florin Coras27bb99e2020-03-17 17:09:12 +00002652 done:
Florin Coras7f969c72021-05-04 14:53:25 -07002653 b += 1;
2654 n_left_from -= 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05002655 }
Florin Coras00cd22d2018-04-18 13:20:18 -07002656
2657 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
Florin Coras7f969c72021-05-04 14:53:25 -07002658 vlib_buffer_free (vm, from, frame->n_vectors);
Florin Coras7ac053b2018-11-05 15:57:21 -08002659
Florin Coras7f969c72021-05-04 14:53:25 -07002660 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002661}
2662
Filip Tehlare275bed2019-03-06 00:06:56 -08002663VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2664 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002665{
2666 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2667}
2668
Filip Tehlare275bed2019-03-06 00:06:56 -08002669VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2670 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002671{
2672 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2673}
2674
2675/* *INDENT-OFF* */
Florin Coras9a1fbb52023-06-08 20:47:11 -07002676VLIB_REGISTER_NODE (tcp4_listen_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002677 .name = "tcp4-listen",
2678 /* Takes a vector of packets. */
2679 .vector_size = sizeof (u32),
2680 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002681 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02002682 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002683};
2684/* *INDENT-ON* */
2685
Dave Barach68b0fb02017-02-28 15:15:56 -05002686/* *INDENT-OFF* */
Florin Coras9a1fbb52023-06-08 20:47:11 -07002687VLIB_REGISTER_NODE (tcp6_listen_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002688 .name = "tcp6-listen",
2689 /* Takes a vector of packets. */
2690 .vector_size = sizeof (u32),
2691 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002692 .error_counters = tcp_input_error_counters,
Clement Durand6cf260c2017-04-13 13:27:04 +02002693 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002694};
2695/* *INDENT-ON* */
2696
Florin Coras9a1fbb52023-06-08 20:47:11 -07002697always_inline uword
2698tcp46_drop_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2699 vlib_frame_t *frame, int is_ip4)
2700{
2701 u32 *from = vlib_frame_vector_args (frame);
2702
2703 /* Error counters must be incremented by previous nodes */
2704 vlib_buffer_free (vm, from, frame->n_vectors);
2705
2706 return frame->n_vectors;
2707}
2708
2709VLIB_NODE_FN (tcp4_drop_node)
2710(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2711{
2712 return tcp46_drop_inline (vm, node, from_frame, 1 /* is_ip4 */);
2713}
2714
2715VLIB_NODE_FN (tcp6_drop_node)
2716(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
2717{
2718 return tcp46_drop_inline (vm, node, from_frame, 0 /* is_ip4 */);
2719}
2720
2721VLIB_REGISTER_NODE (tcp4_drop_node) = {
2722 .name = "tcp4-drop",
2723 .vector_size = sizeof (u32),
2724 .n_errors = TCP_N_ERROR,
2725 .error_counters = tcp_input_error_counters,
2726};
2727
2728VLIB_REGISTER_NODE (tcp6_drop_node) = {
2729 .name = "tcp6-drop",
2730 .vector_size = sizeof (u32),
2731 .n_errors = TCP_N_ERROR,
2732 .error_counters = tcp_input_error_counters,
2733};
2734
2735#define foreach_tcp4_input_next \
2736 _ (DROP, "tcp4-drop") \
2737 _ (LISTEN, "tcp4-listen") \
2738 _ (RCV_PROCESS, "tcp4-rcv-process") \
2739 _ (SYN_SENT, "tcp4-syn-sent") \
2740 _ (ESTABLISHED, "tcp4-established") \
2741 _ (RESET, "tcp4-reset") \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -08002742 _ (PUNT, "ip4-punt")
Dave Barach68b0fb02017-02-28 15:15:56 -05002743
Florin Coras9a1fbb52023-06-08 20:47:11 -07002744#define foreach_tcp6_input_next \
2745 _ (DROP, "tcp6-drop") \
2746 _ (LISTEN, "tcp6-listen") \
2747 _ (RCV_PROCESS, "tcp6-rcv-process") \
2748 _ (SYN_SENT, "tcp6-syn-sent") \
2749 _ (ESTABLISHED, "tcp6-established") \
2750 _ (RESET, "tcp6-reset") \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -08002751 _ (PUNT, "ip6-punt")
Dave Barach68b0fb02017-02-28 15:15:56 -05002752
Dave Barach68b0fb02017-02-28 15:15:56 -05002753#define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2754
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002755static void
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002756tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
2757{
Florin Corasb5e55a22019-01-10 12:42:47 -08002758 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002759 {
2760 *next = TCP_INPUT_NEXT_DROP;
2761 }
2762 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
2763 {
2764 *next = TCP_INPUT_NEXT_PUNT;
2765 *error = TCP_ERROR_PUNT;
2766 }
2767 else
2768 {
2769 *next = TCP_INPUT_NEXT_RESET;
2770 *error = TCP_ERROR_NO_LISTENER;
2771 }
2772}
Dave Barach68b0fb02017-02-28 15:15:56 -05002773
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002774static inline void
Florin Coras045a6ae2023-02-28 12:43:39 -08002775tcp_input_dispatch_buffer (tcp_main_t *tm, tcp_connection_t *tc,
2776 vlib_buffer_t *b, u16 *next, u16 *err_counters)
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002777{
2778 tcp_header_t *tcp;
Florin Corasdeb6f782020-02-11 02:42:36 +00002779 u32 error;
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002780 u8 flags;
2781
2782 tcp = tcp_buffer_hdr (b);
2783 flags = tcp->flags & filter_flags;
2784 *next = tm->dispatch_table[tc->state][flags].next;
Florin Corasdeb6f782020-02-11 02:42:36 +00002785 error = tm->dispatch_table[tc->state][flags].error;
Florin Corasedfe0ee2019-07-29 18:13:25 -07002786 tc->segs_in += 1;
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002787
Michal Kalderon3effadc2021-08-08 04:30:39 -07002788 /* Track connection state when packet was received. It is required
2789 * for @ref tcp46_listen_inline to detect whether we reached
2790 * the node as a result of a SYN packet received while in time-wait
2791 * state. In this case the connection_index in vnet buffer will point
2792 * to the existing tcp connection and not the listener
2793 */
Florin Corasee1cb462020-12-29 09:42:58 -08002794 vnet_buffer (b)->tcp.flags = tc->state;
2795
Florin Corasdeb6f782020-02-11 02:42:36 +00002796 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002797 {
Florin Coras045a6ae2023-02-28 12:43:39 -08002798 tcp_inc_err_counter (err_counters, error, 1);
Florin Corasdeb6f782020-02-11 02:42:36 +00002799 if (error == TCP_ERROR_DISPATCH)
Florin Corasa9d5bea2018-12-17 08:24:19 -08002800 clib_warning ("tcp conn %u disp error state %U flags %U",
Florin Coras360336f2020-02-13 18:46:18 +00002801 tc->c_c_index, format_tcp_state, tc->state,
Florin Corasa9d5bea2018-12-17 08:24:19 -08002802 format_tcp_flags, (int) flags);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002803 }
2804}
2805
2806always_inline uword
2807tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002808 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002809{
2810 u32 n_left_from, *from, thread_index = vm->thread_index;
2811 tcp_main_t *tm = vnet_get_tcp_main ();
2812 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2813 u16 nexts[VLIB_FRAME_SIZE], *next;
Filip Tehlar5035bf02023-02-20 13:46:32 +01002814 u16 err_counters[TCP_N_ERROR] = { 0 };
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002815
Florin Coras8f10b902021-04-02 18:32:00 -07002816 tcp_update_time_now (tcp_get_worker (thread_index));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002817
2818 from = vlib_frame_vector_args (frame);
2819 n_left_from = frame->n_vectors;
2820 vlib_get_buffers (vm, from, bufs, n_left_from);
2821
2822 b = bufs;
2823 next = nexts;
2824
2825 while (n_left_from >= 4)
2826 {
2827 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
2828 tcp_connection_t *tc0, *tc1;
2829
2830 {
2831 vlib_prefetch_buffer_header (b[2], STORE);
2832 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2833
2834 vlib_prefetch_buffer_header (b[3], STORE);
2835 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2836 }
2837
2838 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
2839
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002840 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2841 is_nolookup);
2842 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
2843 is_nolookup);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002844
2845 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2846 {
Srikanth Akulacf4c2102019-11-06 18:53:13 -08002847 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
2848 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002849
2850 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
2851 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
2852
Florin Coras045a6ae2023-02-28 12:43:39 -08002853 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
2854 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], err_counters);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002855 }
2856 else
2857 {
2858 if (PREDICT_TRUE (tc0 != 0))
2859 {
Srikanth Akulacf4c2102019-11-06 18:53:13 -08002860 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002861 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
Florin Coras045a6ae2023-02-28 12:43:39 -08002862 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0],
2863 err_counters);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002864 }
2865 else
Florin Corasdeb6f782020-02-11 02:42:36 +00002866 {
2867 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
Filip Tehlar5035bf02023-02-20 13:46:32 +01002868 tcp_inc_err_counter (err_counters, error0, 1);
Florin Corasdeb6f782020-02-11 02:42:36 +00002869 }
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002870
2871 if (PREDICT_TRUE (tc1 != 0))
2872 {
Srikanth Akulacf4c2102019-11-06 18:53:13 -08002873 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002874 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
Florin Coras045a6ae2023-02-28 12:43:39 -08002875 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1],
2876 err_counters);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002877 }
2878 else
Florin Corasdeb6f782020-02-11 02:42:36 +00002879 {
2880 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
Filip Tehlar5035bf02023-02-20 13:46:32 +01002881 tcp_inc_err_counter (err_counters, error1, 1);
Florin Corasdeb6f782020-02-11 02:42:36 +00002882 }
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002883 }
2884
2885 b += 2;
2886 next += 2;
2887 n_left_from -= 2;
2888 }
2889 while (n_left_from > 0)
2890 {
2891 tcp_connection_t *tc0;
2892 u32 error0 = TCP_ERROR_NO_LISTENER;
2893
2894 if (n_left_from > 1)
2895 {
2896 vlib_prefetch_buffer_header (b[1], STORE);
2897 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2898 }
2899
2900 next[0] = TCP_INPUT_NEXT_DROP;
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002901 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
2902 is_nolookup);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002903 if (PREDICT_TRUE (tc0 != 0))
2904 {
Srikanth Akulacf4c2102019-11-06 18:53:13 -08002905 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002906 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
Florin Coras045a6ae2023-02-28 12:43:39 -08002907 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], err_counters);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002908 }
2909 else
Florin Corasdeb6f782020-02-11 02:42:36 +00002910 {
2911 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
Filip Tehlar5035bf02023-02-20 13:46:32 +01002912 tcp_inc_err_counter (err_counters, error0, 1);
Florin Corasdeb6f782020-02-11 02:42:36 +00002913 }
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002914
2915 b += 1;
2916 next += 1;
2917 n_left_from -= 1;
2918 }
2919
2920 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
Filip Tehlarbc4dc162023-04-17 12:22:12 +02002921 tcp_input_trace_frame (vm, node, bufs, nexts, frame->n_vectors, is_ip4);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002922
Filip Tehlar5035bf02023-02-20 13:46:32 +01002923 tcp_store_err_counters (input, err_counters);
Florin Coras0c8a3bc2018-06-14 17:11:56 -07002924 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2925 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002926}
2927
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002928VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
2929 vlib_node_runtime_t * node,
2930 vlib_frame_t * from_frame)
2931{
2932 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2933 1 /* is_nolookup */ );
2934}
2935
2936VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
2937 vlib_node_runtime_t * node,
2938 vlib_frame_t * from_frame)
2939{
2940 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2941 1 /* is_nolookup */ );
2942}
2943
2944/* *INDENT-OFF* */
2945VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
2946{
2947 .name = "tcp4-input-nolookup",
2948 /* Takes a vector of packets. */
2949 .vector_size = sizeof (u32),
2950 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002951 .error_counters = tcp_input_error_counters,
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002952 .n_next_nodes = TCP_INPUT_N_NEXT,
2953 .next_nodes =
2954 {
2955#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2956 foreach_tcp4_input_next
2957#undef _
2958 },
2959 .format_buffer = format_tcp_header,
2960 .format_trace = format_tcp_rx_trace,
2961};
2962/* *INDENT-ON* */
2963
2964/* *INDENT-OFF* */
2965VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
2966{
2967 .name = "tcp6-input-nolookup",
2968 /* Takes a vector of packets. */
2969 .vector_size = sizeof (u32),
2970 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00002971 .error_counters = tcp_input_error_counters,
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002972 .n_next_nodes = TCP_INPUT_N_NEXT,
2973 .next_nodes =
2974 {
2975#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
2976 foreach_tcp6_input_next
2977#undef _
2978 },
2979 .format_buffer = format_tcp_header,
2980 .format_trace = format_tcp_rx_trace,
2981};
2982/* *INDENT-ON* */
2983
Filip Tehlare275bed2019-03-06 00:06:56 -08002984VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2985 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002986{
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002987 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
2988 0 /* is_nolookup */ );
Dave Barach68b0fb02017-02-28 15:15:56 -05002989}
2990
Filip Tehlare275bed2019-03-06 00:06:56 -08002991VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2992 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002993{
Vladimir Kropylev456d2f92019-07-16 21:22:29 +03002994 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
2995 0 /* is_nolookup */ );
Dave Barach68b0fb02017-02-28 15:15:56 -05002996}
2997
2998/* *INDENT-OFF* */
2999VLIB_REGISTER_NODE (tcp4_input_node) =
3000{
Dave Barach68b0fb02017-02-28 15:15:56 -05003001 .name = "tcp4-input",
3002 /* Takes a vector of packets. */
3003 .vector_size = sizeof (u32),
3004 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00003005 .error_counters = tcp_input_error_counters,
Dave Barach68b0fb02017-02-28 15:15:56 -05003006 .n_next_nodes = TCP_INPUT_N_NEXT,
3007 .next_nodes =
3008 {
3009#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3010 foreach_tcp4_input_next
3011#undef _
3012 },
3013 .format_buffer = format_tcp_header,
3014 .format_trace = format_tcp_rx_trace,
3015};
3016/* *INDENT-ON* */
3017
Dave Barach68b0fb02017-02-28 15:15:56 -05003018/* *INDENT-OFF* */
3019VLIB_REGISTER_NODE (tcp6_input_node) =
3020{
Dave Barach68b0fb02017-02-28 15:15:56 -05003021 .name = "tcp6-input",
3022 /* Takes a vector of packets. */
3023 .vector_size = sizeof (u32),
3024 .n_errors = TCP_N_ERROR,
Filip Tehlar0c4931c2021-10-06 09:47:41 +00003025 .error_counters = tcp_input_error_counters,
Dave Barach68b0fb02017-02-28 15:15:56 -05003026 .n_next_nodes = TCP_INPUT_N_NEXT,
3027 .next_nodes =
3028 {
3029#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3030 foreach_tcp6_input_next
3031#undef _
3032 },
3033 .format_buffer = format_tcp_header,
3034 .format_trace = format_tcp_rx_trace,
3035};
3036/* *INDENT-ON* */
3037
Filip Tehlare275bed2019-03-06 00:06:56 -08003038#ifndef CLIB_MARCH_VARIANT
Florin Coras04ae8272021-04-12 19:55:37 -07003039void
3040tcp_check_gso (tcp_connection_t *tc)
3041{
3042 tcp_check_tx_offload (tc, tc->c_is_ip4);
3043}
3044
Dave Barach68b0fb02017-02-28 15:15:56 -05003045static void
3046tcp_dispatch_table_init (tcp_main_t * tm)
3047{
3048 int i, j;
3049 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3050 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3051 {
3052 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3053 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3054 }
3055
3056#define _(t,f,n,e) \
3057do { \
3058 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3059 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3060} while (0)
3061
Florin Coras678a6572018-12-17 21:31:25 -08003062 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
Florin Coras5c0f1662018-12-19 01:38:57 -08003063 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Florin Coras678a6572018-12-17 21:31:25 -08003064 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3065 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
Dave Barach68b0fb02017-02-28 15:15:56 -05003066 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003067 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3068 TCP_ERROR_ACK_INVALID);
3069 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3070 TCP_ERROR_SEGMENT_INVALID);
3071 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3072 TCP_ERROR_SEGMENT_INVALID);
3073 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3074 TCP_ERROR_INVALID_CONNECTION);
3075 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
Dave Barach2c25a622017-06-26 11:35:07 -04003076 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
Florin Coras678a6572018-12-17 21:31:25 -08003077 TCP_ERROR_SEGMENT_INVALID);
3078 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3079 TCP_ERROR_SEGMENT_INVALID);
3080 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
Florin Corasdeb6f782020-02-11 02:42:36 +00003081 TCP_ERROR_SEGMENT_INVALID);
Florin Coras678a6572018-12-17 21:31:25 -08003082 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3083 TCP_ERROR_SEGMENT_INVALID);
3084 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3085 TCP_ERROR_SEGMENT_INVALID);
3086 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3087 TCP_ERROR_SEGMENT_INVALID);
3088 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3089 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Dave Barach68b0fb02017-02-28 15:15:56 -05003090 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3091 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasc28764f2017-04-26 00:08:42 -07003092 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corase8460c72018-09-24 14:40:40 -07003093 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3094 TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003095 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003096 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3097 TCP_ERROR_NONE);
3098 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3099 TCP_ERROR_NONE);
3100 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3101 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3102 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasc01c4452018-09-20 18:36:54 -07003103 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3104 TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003105 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3106 TCP_ERROR_NONE);
3107 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3108 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3109 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3110 TCP_ERROR_NONE);
3111 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3112 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3113 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3114 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3115 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3116 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3117 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Dave Barach68b0fb02017-02-28 15:15:56 -05003118 /* SYN-ACK for a SYN */
3119 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3120 TCP_ERROR_NONE);
3121 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3122 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3123 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3124 TCP_ERROR_NONE);
Florin Coras222e1f412019-02-16 20:47:32 -08003125 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3126 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3127 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003128 /* ACK for for established connection -> tcp-established. */
3129 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3130 /* FIN for for established connection -> tcp-established. */
3131 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3132 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3133 TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003134 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3135 TCP_ERROR_NONE);
3136 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3137 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3138 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3139 TCP_ERROR_NONE);
3140 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3141 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3142 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3143 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3144 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3145 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Corasd79b41e2017-03-04 05:37:52 -08003146 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Corasdc629cd2017-05-09 00:52:37 -07003147 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3148 TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003149 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Coras3eb50622017-07-13 01:24:57 -04003150 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3151 TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003152 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3153 TCP_ERROR_NONE);
3154 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3155 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3156 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Dave Barach68b0fb02017-02-28 15:15:56 -05003157 /* ACK or FIN-ACK to our FIN */
3158 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3159 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3160 TCP_ERROR_NONE);
3161 /* FIN in reply to our FIN from the other side */
Florin Coras76bc1302018-12-23 23:36:36 -08003162 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Dave Barach68b0fb02017-02-28 15:15:56 -05003163 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras76bc1302018-12-23 23:36:36 -08003164 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3165 TCP_ERROR_NONE);
3166 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3167 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3168 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3169 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3170 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3171 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3172 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3173 TCP_ERROR_NONE);
3174 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3175 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras5c0f1662018-12-19 01:38:57 -08003176 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras76bc1302018-12-23 23:36:36 -08003177 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3178 TCP_ERROR_NONE);
3179 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3180 TCP_ERROR_NONE);
3181 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3182 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003183 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corase96bf632018-12-18 22:44:27 -08003184 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3185 TCP_ERROR_NONE);
Florin Corasb56fcf12019-01-02 10:10:08 -08003186 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Florin Coras56318932018-05-23 20:44:12 -07003187 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras54ddf432018-12-21 13:54:09 -08003188 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasb56fcf12019-01-02 10:10:08 -08003189 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3190 TCP_ERROR_NONE);
3191 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3192 TCP_ERROR_NONE);
3193 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3194 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras54ddf432018-12-21 13:54:09 -08003195 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3196 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3197 TCP_ERROR_NONE);
Florin Corasb56fcf12019-01-02 10:10:08 -08003198 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras3c514d52018-12-22 11:39:33 -08003199 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3200 TCP_ERROR_NONE);
Florin Corasb56fcf12019-01-02 10:10:08 -08003201 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3202 TCP_ERROR_NONE);
3203 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3204 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3205 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3206 TCP_ERROR_NONE);
3207 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3208 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras79c04d62019-08-11 19:49:05 -07003209 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3210 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasb56fcf12019-01-02 10:10:08 -08003211 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3212 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003213 /* FIN confirming that the peer (app) has closed */
3214 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasf6d68ed2017-05-07 19:12:02 -07003215 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003216 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3217 TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003218 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3219 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3220 TCP_ERROR_NONE);
Florin Corasf9512bf2020-07-29 10:13:07 -07003221 _(FIN_WAIT_2, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras61d63e82023-10-14 15:22:04 -07003222 _ (FIN_WAIT_2, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3223 TCP_ERROR_NONE);
Florin Corasf03a59a2017-06-09 21:07:32 -07003224 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3225 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3226 TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003227 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3228 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3229 TCP_ERROR_NONE);
Florin Corasd75213f2020-07-28 10:57:09 -07003230 _(CLOSE_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasd12ff502018-12-25 10:55:01 -08003231 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
Dave Barach68b0fb02017-02-28 15:15:56 -05003232 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras93992a92017-05-24 18:03:56 -07003233 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3234 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3235 TCP_ERROR_NONE);
Florin Corasd12ff502018-12-25 10:55:01 -08003236 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3237 TCP_ERROR_NONE);
3238 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3239 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3240 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3241 TCP_ERROR_NONE);
3242 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3243 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3244 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3245 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3246 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3247 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasdb84e572017-05-09 18:54:52 -07003248 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003249 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3250 TCP_ERROR_NONE);
Florin Corasc01d5782018-10-17 14:53:11 -07003251 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasd12ff502018-12-25 10:55:01 -08003252 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3253 TCP_ERROR_NONE);
3254 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3255 TCP_ERROR_NONE);
3256 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3257 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Yu Pingb092b772019-12-27 04:04:33 +08003258 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
Florin Coras93992a92017-05-24 18:03:56 -07003259 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3260 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3261 TCP_ERROR_NONE);
Florin Coras3eb50622017-07-13 01:24:57 -04003262 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003263 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3264 TCP_ERROR_NONE);
Florin Coras50958952017-08-29 14:50:13 -07003265 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003266 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3267 * incoming segment not containing a RST causes a RST to be sent in
3268 * response.*/
Florin Corasdc629cd2017-05-09 00:52:37 -07003269 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
Florin Coras678a6572018-12-17 21:31:25 -08003270 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
Dave Barach2c25a622017-06-26 11:35:07 -04003271 TCP_ERROR_CONNECTION_CLOSED);
Florin Corasdeb6f782020-02-11 02:42:36 +00003272 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
Florin Coras3ffc77d2023-02-16 18:59:38 -08003273 _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
Florin Coras678a6572018-12-17 21:31:25 -08003274 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
Florin Corasdeb6f782020-02-11 02:42:36 +00003275 TCP_ERROR_CONNECTION_CLOSED);
Dave Barach68b0fb02017-02-28 15:15:56 -05003276#undef _
3277}
3278
Florin Coras0dbd5172018-06-25 16:19:34 -07003279static clib_error_t *
Dave Barach68b0fb02017-02-28 15:15:56 -05003280tcp_input_init (vlib_main_t * vm)
3281{
3282 clib_error_t *error = 0;
3283 tcp_main_t *tm = vnet_get_tcp_main ();
3284
3285 if ((error = vlib_call_init_function (vm, tcp_init)))
3286 return error;
3287
3288 /* Initialize dispatch table. */
3289 tcp_dispatch_table_init (tm);
3290
3291 return error;
3292}
3293
3294VLIB_INIT_FUNCTION (tcp_input_init);
3295
Filip Tehlare275bed2019-03-06 00:06:56 -08003296#endif /* CLIB_MARCH_VARIANT */
3297
Dave Barach68b0fb02017-02-28 15:15:56 -05003298/*
3299 * fd.io coding-style-patch-verification: ON
3300 *
3301 * Local Variables:
3302 * eval: (c-set-style "gnu")
3303 * End:
3304 */