blob: 252b0014c8c8e65702e600643e1148c29e4a860a [file] [log] [blame]
Dave Barach68b0fb02017-02-28 15:15:56 -05001/*
2 * Copyright (c) 2016 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
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>
17#include <vnet/tcp/tcp_packet.h>
18#include <vnet/tcp/tcp.h>
19#include <vnet/session/session.h>
20#include <math.h>
21
22static char *tcp_error_strings[] = {
23#define tcp_error(n,s) s,
24#include <vnet/tcp/tcp_error.def>
25#undef tcp_error
26};
27
28/* All TCP nodes have the same outgoing arcs */
29#define foreach_tcp_state_next \
30 _ (DROP, "error-drop") \
31 _ (TCP4_OUTPUT, "tcp4-output") \
32 _ (TCP6_OUTPUT, "tcp6-output")
33
34typedef enum _tcp_established_next
35{
36#define _(s,n) TCP_ESTABLISHED_NEXT_##s,
37 foreach_tcp_state_next
38#undef _
39 TCP_ESTABLISHED_N_NEXT,
40} tcp_established_next_t;
41
42typedef enum _tcp_rcv_process_next
43{
44#define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
45 foreach_tcp_state_next
46#undef _
47 TCP_RCV_PROCESS_N_NEXT,
48} tcp_rcv_process_next_t;
49
50typedef enum _tcp_syn_sent_next
51{
52#define _(s,n) TCP_SYN_SENT_NEXT_##s,
53 foreach_tcp_state_next
54#undef _
55 TCP_SYN_SENT_N_NEXT,
56} tcp_syn_sent_next_t;
57
58typedef enum _tcp_listen_next
59{
60#define _(s,n) TCP_LISTEN_NEXT_##s,
61 foreach_tcp_state_next
62#undef _
63 TCP_LISTEN_N_NEXT,
64} tcp_listen_next_t;
65
66/* Generic, state independent indices */
67typedef enum _tcp_state_next
68{
69#define _(s,n) TCP_NEXT_##s,
70 foreach_tcp_state_next
71#undef _
72 TCP_STATE_N_NEXT,
73} tcp_state_next_t;
74
75#define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
76 : TCP_NEXT_TCP6_OUTPUT)
77
78vlib_node_registration_t tcp4_established_node;
79vlib_node_registration_t tcp6_established_node;
80
81/**
82 * Validate segment sequence number. As per RFC793:
83 *
84 * Segment Receive Test
85 * Length Window
86 * ------- ------- -------------------------------------------
87 * 0 0 SEG.SEQ = RCV.NXT
88 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
89 * >0 0 not acceptable
90 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
91 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
92 *
93 * This ultimately consists in checking if segment falls within the window.
94 * The one important difference compared to RFC793 is that we use rcv_las,
95 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
96 * peer's reference when computing our receive window.
97 *
Florin Coras6792ec02017-03-13 03:49:51 -070098 * This:
99 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
100 * however, is too strict when we have retransmits. Instead we just check that
101 * the seq is not beyond the right edge and that the end of the segment is not
102 * less than the left edge.
103 *
104 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
105 * use rcv_nxt in the right edge window test instead of rcv_las.
106 *
Dave Barach68b0fb02017-02-28 15:15:56 -0500107 */
108always_inline u8
109tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
110{
Florin Coras6792ec02017-03-13 03:49:51 -0700111 return (seq_geq (end_seq, tc->rcv_las)
112 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
Dave Barach68b0fb02017-02-28 15:15:56 -0500113}
114
Florin Corasdb84e572017-05-09 18:54:52 -0700115/**
116 * Parse TCP header options.
117 *
118 * @param th TCP header
119 * @param to TCP options data structure to be populated
120 * @return -1 if parsing failed
121 */
122int
Dave Barach68b0fb02017-02-28 15:15:56 -0500123tcp_options_parse (tcp_header_t * th, tcp_options_t * to)
124{
125 const u8 *data;
126 u8 opt_len, opts_len, kind;
127 int j;
128 sack_block_t b;
129
130 opts_len = (tcp_doff (th) << 2) - sizeof (tcp_header_t);
131 data = (const u8 *) (th + 1);
132
133 /* Zero out all flags but those set in SYN */
134 to->flags &= (TCP_OPTS_FLAG_SACK_PERMITTED | TCP_OPTS_FLAG_WSCALE);
135
136 for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
137 {
138 kind = data[0];
139
140 /* Get options length */
141 if (kind == TCP_OPTION_EOL)
142 break;
143 else if (kind == TCP_OPTION_NOOP)
Florin Corasdb84e572017-05-09 18:54:52 -0700144 {
145 opt_len = 1;
146 continue;
147 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500148 else
149 {
150 /* broken options */
151 if (opts_len < 2)
Florin Corasdb84e572017-05-09 18:54:52 -0700152 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500153 opt_len = data[1];
154
155 /* weird option length */
156 if (opt_len < 2 || opt_len > opts_len)
Florin Corasdb84e572017-05-09 18:54:52 -0700157 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500158 }
159
160 /* Parse options */
161 switch (kind)
162 {
163 case TCP_OPTION_MSS:
164 if ((opt_len == TCP_OPTION_LEN_MSS) && tcp_syn (th))
165 {
166 to->flags |= TCP_OPTS_FLAG_MSS;
167 to->mss = clib_net_to_host_u16 (*(u16 *) (data + 2));
168 }
169 break;
170 case TCP_OPTION_WINDOW_SCALE:
171 if ((opt_len == TCP_OPTION_LEN_WINDOW_SCALE) && tcp_syn (th))
172 {
173 to->flags |= TCP_OPTS_FLAG_WSCALE;
174 to->wscale = data[2];
175 if (to->wscale > TCP_MAX_WND_SCALE)
176 {
177 clib_warning ("Illegal window scaling value: %d",
178 to->wscale);
179 to->wscale = TCP_MAX_WND_SCALE;
180 }
181 }
182 break;
183 case TCP_OPTION_TIMESTAMP:
184 if (opt_len == TCP_OPTION_LEN_TIMESTAMP)
185 {
186 to->flags |= TCP_OPTS_FLAG_TSTAMP;
187 to->tsval = clib_net_to_host_u32 (*(u32 *) (data + 2));
188 to->tsecr = clib_net_to_host_u32 (*(u32 *) (data + 6));
189 }
190 break;
191 case TCP_OPTION_SACK_PERMITTED:
192 if (opt_len == TCP_OPTION_LEN_SACK_PERMITTED && tcp_syn (th))
193 to->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
194 break;
195 case TCP_OPTION_SACK_BLOCK:
196 /* If SACK permitted was not advertised or a SYN, break */
197 if ((to->flags & TCP_OPTS_FLAG_SACK_PERMITTED) == 0 || tcp_syn (th))
198 break;
199
200 /* If too short or not correctly formatted, break */
201 if (opt_len < 10 || ((opt_len - 2) % TCP_OPTION_LEN_SACK_BLOCK))
202 break;
203
204 to->flags |= TCP_OPTS_FLAG_SACK;
205 to->n_sack_blocks = (opt_len - 2) / TCP_OPTION_LEN_SACK_BLOCK;
206 vec_reset_length (to->sacks);
207 for (j = 0; j < to->n_sack_blocks; j++)
208 {
Florin Coras3eb50622017-07-13 01:24:57 -0400209 b.start = clib_net_to_host_u32 (*(u32 *) (data + 2 + 8 * j));
210 b.end = clib_net_to_host_u32 (*(u32 *) (data + 6 + 8 * j));
Dave Barach68b0fb02017-02-28 15:15:56 -0500211 vec_add1 (to->sacks, b);
212 }
213 break;
214 default:
215 /* Nothing to see here */
216 continue;
217 }
218 }
Florin Corasdb84e572017-05-09 18:54:52 -0700219 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500220}
221
Florin Corasc28764f2017-04-26 00:08:42 -0700222/**
223 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
224 * timestamp to echo and it's less than tsval_recent, drop segment
225 * but still send an ACK in order to retain TCP's mechanism for detecting
226 * and recovering from half-open connections
227 *
228 * Or at least that's what the theory says. It seems that this might not work
229 * very well with packet reordering and fast retransmit. XXX
230 */
Dave Barach68b0fb02017-02-28 15:15:56 -0500231always_inline int
232tcp_segment_check_paws (tcp_connection_t * tc)
233{
Florin Coras93992a92017-05-24 18:03:56 -0700234 return tcp_opts_tstamp (&tc->rcv_opts) && tc->tsval_recent
235 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
Dave Barach68b0fb02017-02-28 15:15:56 -0500236}
237
238/**
Florin Corasc28764f2017-04-26 00:08:42 -0700239 * Update tsval recent
240 */
241always_inline void
242tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
243{
244 /*
245 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
246 * of an incoming segment:
247 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
248 * then the TSval from the segment is copied to TS.Recent;
249 * otherwise, the TSval is ignored.
250 */
Florin Corasf1762d62017-09-24 19:43:08 -0400251 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
252 && seq_leq (tc->rcv_las, seq_end))
Florin Corasc28764f2017-04-26 00:08:42 -0700253 {
Dave Barach2c25a622017-06-26 11:35:07 -0400254 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
Florin Coras93992a92017-05-24 18:03:56 -0700255 tc->tsval_recent = tc->rcv_opts.tsval;
Florin Corasc28764f2017-04-26 00:08:42 -0700256 tc->tsval_recent_age = tcp_time_now ();
257 }
258}
259
260/**
Dave Barach68b0fb02017-02-28 15:15:56 -0500261 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
262 *
263 * It first verifies if segment has a wrapped sequence number (PAWS) and then
264 * does the processing associated to the first four steps (ignoring security
265 * and precedence): sequence number, rst bit and syn bit checks.
266 *
267 * @return 0 if segments passes validation.
268 */
269static int
270tcp_segment_validate (vlib_main_t * vm, tcp_connection_t * tc0,
271 vlib_buffer_t * b0, tcp_header_t * th0, u32 * next0)
272{
Dave Barach68b0fb02017-02-28 15:15:56 -0500273 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
274 return -1;
275
Florin Coras93992a92017-05-24 18:03:56 -0700276 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts)))
Florin Corasdb84e572017-05-09 18:54:52 -0700277 {
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400278 clib_warning ("options parse error");
Florin Corasdb84e572017-05-09 18:54:52 -0700279 return -1;
280 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500281
Florin Corasc28764f2017-04-26 00:08:42 -0700282 if (tcp_segment_check_paws (tc0))
Dave Barach68b0fb02017-02-28 15:15:56 -0500283 {
Florin Coras93992a92017-05-24 18:03:56 -0700284 if (CLIB_DEBUG > 2)
285 {
286 clib_warning ("paws failed\n%U", format_tcp_connection, tc0, 2);
287 clib_warning ("seq %u seq_end %u ack %u",
288 vnet_buffer (b0)->tcp.seq_number - tc0->irs,
289 vnet_buffer (b0)->tcp.seq_end - tc0->irs,
290 vnet_buffer (b0)->tcp.ack_number - tc0->iss);
291 }
Florin Corasc28764f2017-04-26 00:08:42 -0700292 TCP_EVT_DBG (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
293 vnet_buffer (b0)->tcp.seq_end);
Dave Barach68b0fb02017-02-28 15:15:56 -0500294
295 /* If it just so happens that a segment updates tsval_recent for a
296 * segment over 24 days old, invalidate tsval_recent. */
297 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
298 tcp_time_now ()))
299 {
300 /* Age isn't reset until we get a valid tsval (bsd inspired) */
301 tc0->tsval_recent = 0;
Florin Corasc28764f2017-04-26 00:08:42 -0700302 clib_warning ("paws failed - really old segment. REALLY?");
Dave Barach68b0fb02017-02-28 15:15:56 -0500303 }
304 else
305 {
306 /* Drop after ack if not rst */
307 if (!tcp_rst (th0))
308 {
309 tcp_make_ack (tc0, b0);
310 *next0 = tcp_next_output (tc0->c_is_ip4);
Florin Coras6792ec02017-03-13 03:49:51 -0700311 TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500312 return -1;
313 }
314 }
315 }
316
317 /* 1st: check sequence number */
318 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
319 vnet_buffer (b0)->tcp.seq_end))
320 {
Florin Coras6792ec02017-03-13 03:49:51 -0700321 /* If our window is 0 and the packet is in sequence, let it pass
322 * through for ack processing. It should be dropped later.*/
323 if (tc0->rcv_wnd == 0
324 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
Dave Barach68b0fb02017-02-28 15:15:56 -0500325 {
Florin Coras3e350af2017-03-30 02:54:28 -0700326 /* TODO Should segment be tagged? */
Dave Barach68b0fb02017-02-28 15:15:56 -0500327 }
Florin Coras6792ec02017-03-13 03:49:51 -0700328 else
329 {
330 /* If not RST, send dup ack */
331 if (!tcp_rst (th0))
332 {
333 tcp_make_ack (tc0, b0);
334 *next0 = tcp_next_output (tc0->c_is_ip4);
335 TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc0);
336 }
337 return -1;
338 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500339 }
340
341 /* 2nd: check the RST bit */
342 if (tcp_rst (th0))
343 {
Florin Corasd79b41e2017-03-04 05:37:52 -0800344 tcp_connection_reset (tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500345 return -1;
346 }
347
348 /* 3rd: check security and precedence (skip) */
349
350 /* 4th: check the SYN bit */
351 if (tcp_syn (th0))
352 {
Florin Coras6534b7a2017-07-18 05:38:03 -0400353 /* TODO implement RFC 5961 */
Florin Coras9d063042017-09-14 03:08:00 -0400354 if (tc0->state == TCP_STATE_SYN_RCVD)
355 {
356 tcp_make_synack (tc0, b0);
357 TCP_EVT_DBG (TCP_EVT_SYN_RCVD, tc0, 0);
358 }
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400359 else
Florin Coras9d063042017-09-14 03:08:00 -0400360 {
361 tcp_make_ack (tc0, b0);
362 TCP_EVT_DBG (TCP_EVT_SYNACK_RCVD, tc0);
363 }
Florin Coras6534b7a2017-07-18 05:38:03 -0400364 *next0 = tcp_next_output (tc0->c_is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -0500365 return -1;
366 }
367
Florin Corasc28764f2017-04-26 00:08:42 -0700368 /* If segment in window, save timestamp */
369 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
370 vnet_buffer (b0)->tcp.seq_end);
Dave Barach68b0fb02017-02-28 15:15:56 -0500371 return 0;
372}
373
374always_inline int
375tcp_rcv_ack_is_acceptable (tcp_connection_t * tc0, vlib_buffer_t * tb0)
376{
377 /* SND.UNA =< SEG.ACK =< SND.NXT */
378 return (seq_leq (tc0->snd_una, vnet_buffer (tb0)->tcp.ack_number)
379 && seq_leq (vnet_buffer (tb0)->tcp.ack_number, tc0->snd_nxt));
380}
381
382/**
383 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
384 *
385 * Note that although the original article, srtt and rttvar are scaled
386 * to minimize round-off errors, here we don't. Instead, we rely on
387 * better precision time measurements.
388 *
389 * TODO support us rtt resolution
390 */
391static void
392tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
393{
Florin Corasf03a59a2017-06-09 21:07:32 -0700394 int err, diff;
Dave Barach68b0fb02017-02-28 15:15:56 -0500395
396 if (tc->srtt != 0)
397 {
398 err = mrtt - tc->srtt;
Dave Barach68b0fb02017-02-28 15:15:56 -0500399
400 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
401 * The increase should be bound */
Florin Corasf03a59a2017-06-09 21:07:32 -0700402 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
403 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
404 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500405 }
406 else
407 {
408 /* First measurement. */
409 tc->srtt = mrtt;
Florin Coras6792ec02017-03-13 03:49:51 -0700410 tc->rttvar = mrtt >> 1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500411 }
412}
413
Florin Coras93992a92017-05-24 18:03:56 -0700414void
415tcp_update_rto (tcp_connection_t * tc)
416{
417 tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
Florin Corasf03a59a2017-06-09 21:07:32 -0700418 tc->rto = clib_max (tc->rto, TCP_RTO_MIN);
Florin Coras93992a92017-05-24 18:03:56 -0700419}
420
Florin Corasf1762d62017-09-24 19:43:08 -0400421/**
422 * Update RTT estimate and RTO timer
Dave Barach68b0fb02017-02-28 15:15:56 -0500423 *
424 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
425 * timing. Middle boxes are known to fiddle with TCP options so we
426 * should give higher priority to ACK timing.
427 *
Florin Corasf1762d62017-09-24 19:43:08 -0400428 * This should be called only if previously sent bytes have been acked.
429 *
Dave Barach68b0fb02017-02-28 15:15:56 -0500430 * return 1 if valid rtt 0 otherwise
431 */
432static int
433tcp_update_rtt (tcp_connection_t * tc, u32 ack)
434{
435 u32 mrtt = 0;
436
437 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
438 * RTT because they're ambiguous. */
Florin Corasf1762d62017-09-24 19:43:08 -0400439 if (tcp_in_cong_recovery (tc) || tc->sack_sb.sacked_bytes)
440 goto done;
441
442 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
Dave Barach68b0fb02017-02-28 15:15:56 -0500443 {
444 mrtt = tcp_time_now () - tc->rtt_ts;
Dave Barach68b0fb02017-02-28 15:15:56 -0500445 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500446 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
447 * snd_una, i.e., the left side of the send window:
Florin Corasf1762d62017-09-24 19:43:08 -0400448 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
449 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
Dave Barach68b0fb02017-02-28 15:15:56 -0500450 {
Florin Coras93992a92017-05-24 18:03:56 -0700451 mrtt = tcp_time_now () - tc->rcv_opts.tsecr;
Dave Barach68b0fb02017-02-28 15:15:56 -0500452 }
453
Florin Corasf1762d62017-09-24 19:43:08 -0400454 /* Ignore dubious measurements */
455 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
456 goto done;
457
458 tcp_estimate_rtt (tc, mrtt);
459
460done:
461
Florin Coras3af90fc2017-05-03 21:09:42 -0700462 /* Allow measuring of a new RTT */
463 tc->rtt_ts = 0;
464
Florin Corasf1762d62017-09-24 19:43:08 -0400465 /* If we got here something must've been ACKed so make sure boff is 0,
466 * even if mrrt is not valid since we update the rto lower */
467 tc->rto_boff = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700468 tcp_update_rto (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500469
Florin Coras3af90fc2017-05-03 21:09:42 -0700470 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500471}
472
473/**
474 * Dequeue bytes that have been acked and while at it update RTT estimates.
475 */
476static void
477tcp_dequeue_acked (tcp_connection_t * tc, u32 ack)
478{
Florin Coras93992a92017-05-24 18:03:56 -0700479 /* Dequeue the newly ACKed add SACKed bytes */
480 stream_session_dequeue_drop (&tc->connection,
481 tc->bytes_acked + tc->sack_sb.snd_una_adv);
482
483 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
Dave Barach68b0fb02017-02-28 15:15:56 -0500484
485 /* Update rtt and rto */
Florin Coras3e350af2017-03-30 02:54:28 -0700486 tcp_update_rtt (tc, ack);
Florin Coras93992a92017-05-24 18:03:56 -0700487
488 /* If everything has been acked, stop retransmit timer
489 * otherwise update. */
490 tcp_retransmit_timer_update (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500491}
492
Florin Coras6792ec02017-03-13 03:49:51 -0700493/**
Florin Coras93992a92017-05-24 18:03:56 -0700494 * Check if duplicate ack as per RFC5681 Sec. 2
495 */
496static u8
497tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
498 u32 prev_snd_una)
Dave Barach68b0fb02017-02-28 15:15:56 -0500499{
Florin Coras93992a92017-05-24 18:03:56 -0700500 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
Dave Barach68b0fb02017-02-28 15:15:56 -0500501 && seq_gt (tc->snd_una_max, tc->snd_una)
502 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
Florin Coras93992a92017-05-24 18:03:56 -0700503 && (prev_snd_wnd == tc->snd_wnd));
504}
505
506/**
507 * Checks if ack is a congestion control event.
508 */
509static u8
510tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
511 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
512{
513 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
514 * defined to be 'duplicate' */
515 *is_dack = tc->sack_sb.last_sacked_bytes
516 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
517
Dave Barach2c25a622017-06-26 11:35:07 -0400518 return ((*is_dack || tcp_in_cong_recovery (tc)) && !tcp_is_lost_fin (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500519}
520
521void
522scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
523{
524 sack_scoreboard_hole_t *next, *prev;
525
526 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
527 {
528 next = pool_elt_at_index (sb->holes, hole->next);
529 next->prev = hole->prev;
530 }
Florin Coras93992a92017-05-24 18:03:56 -0700531 else
532 {
533 sb->tail = hole->prev;
534 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500535
536 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
537 {
538 prev = pool_elt_at_index (sb->holes, hole->prev);
539 prev->next = hole->next;
540 }
541 else
542 {
543 sb->head = hole->next;
544 }
545
Florin Coras93992a92017-05-24 18:03:56 -0700546 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
547 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
548
Florin Coras3eb50622017-07-13 01:24:57 -0400549 /* Poison the entry */
550 if (CLIB_DEBUG > 0)
551 memset (hole, 0xfe, sizeof (*hole));
552
Dave Barach68b0fb02017-02-28 15:15:56 -0500553 pool_put (sb->holes, hole);
554}
555
556sack_scoreboard_hole_t *
Florin Coras6792ec02017-03-13 03:49:51 -0700557scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
Dave Barach68b0fb02017-02-28 15:15:56 -0500558 u32 start, u32 end)
559{
Florin Coras6792ec02017-03-13 03:49:51 -0700560 sack_scoreboard_hole_t *hole, *next, *prev;
Dave Barach68b0fb02017-02-28 15:15:56 -0500561 u32 hole_index;
562
563 pool_get (sb->holes, hole);
564 memset (hole, 0, sizeof (*hole));
565
566 hole->start = start;
567 hole->end = end;
Florin Coras3eb50622017-07-13 01:24:57 -0400568 hole_index = scoreboard_hole_index (sb, hole);
Dave Barach68b0fb02017-02-28 15:15:56 -0500569
Florin Coras6792ec02017-03-13 03:49:51 -0700570 prev = scoreboard_get_hole (sb, prev_index);
Dave Barach68b0fb02017-02-28 15:15:56 -0500571 if (prev)
572 {
Florin Corasf03a59a2017-06-09 21:07:32 -0700573 hole->prev = prev_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500574 hole->next = prev->next;
575
576 if ((next = scoreboard_next_hole (sb, hole)))
577 next->prev = hole_index;
Florin Corasf03a59a2017-06-09 21:07:32 -0700578 else
579 sb->tail = hole_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500580
581 prev->next = hole_index;
582 }
583 else
584 {
585 sb->head = hole_index;
586 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
587 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
588 }
589
590 return hole;
591}
592
Florin Coras6792ec02017-03-13 03:49:51 -0700593void
Florin Corasf03a59a2017-06-09 21:07:32 -0700594scoreboard_update_bytes (tcp_connection_t * tc, sack_scoreboard_t * sb)
Florin Coras93992a92017-05-24 18:03:56 -0700595{
596 sack_scoreboard_hole_t *hole, *prev;
597 u32 bytes = 0, blks = 0;
598
599 sb->lost_bytes = 0;
Florin Corasf03a59a2017-06-09 21:07:32 -0700600 sb->sacked_bytes = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700601 hole = scoreboard_last_hole (sb);
602 if (!hole)
603 return;
604
605 if (seq_gt (sb->high_sacked, hole->end))
606 {
607 bytes = sb->high_sacked - hole->end;
608 blks = 1;
609 }
610
611 while ((prev = scoreboard_prev_hole (sb, hole))
612 && (bytes < (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
613 && blks < TCP_DUPACK_THRESHOLD))
614 {
615 bytes += hole->start - prev->end;
616 blks++;
617 hole = prev;
618 }
619
Florin Coras93992a92017-05-24 18:03:56 -0700620 while (hole)
621 {
622 sb->lost_bytes += scoreboard_hole_bytes (hole);
623 hole->is_lost = 1;
Florin Corasf03a59a2017-06-09 21:07:32 -0700624 prev = hole;
Florin Coras93992a92017-05-24 18:03:56 -0700625 hole = scoreboard_prev_hole (sb, hole);
Florin Corasf03a59a2017-06-09 21:07:32 -0700626 if (hole)
627 bytes += prev->start - hole->end;
Florin Coras93992a92017-05-24 18:03:56 -0700628 }
Florin Corasf03a59a2017-06-09 21:07:32 -0700629 sb->sacked_bytes = bytes;
Florin Coras93992a92017-05-24 18:03:56 -0700630}
631
632/**
633 * Figure out the next hole to retransmit
634 *
635 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
636 */
637sack_scoreboard_hole_t *
638scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
639 sack_scoreboard_hole_t * start,
640 u8 have_sent_1_smss,
641 u8 * can_rescue, u8 * snd_limited)
642{
643 sack_scoreboard_hole_t *hole = 0;
644
645 hole = start ? start : scoreboard_first_hole (sb);
646 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
647 hole = scoreboard_next_hole (sb, hole);
648
649 /* Nothing, return */
650 if (!hole)
651 {
652 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
653 return 0;
654 }
655
656 /* Rule (1): if higher than rxt, less than high_sacked and lost */
657 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
658 {
659 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
660 }
661 else
662 {
663 /* Rule (2): output takes care of transmitting new data */
664 if (!have_sent_1_smss)
665 {
666 hole = 0;
667 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
668 }
669 /* Rule (3): if hole not lost */
670 else if (seq_lt (hole->start, sb->high_sacked))
671 {
672 *snd_limited = 1;
673 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
674 }
675 /* Rule (4): if hole beyond high_sacked */
676 else
677 {
678 ASSERT (seq_geq (hole->start, sb->high_sacked));
679 *snd_limited = 1;
680 *can_rescue = 1;
681 /* HighRxt MUST NOT be updated */
682 return 0;
683 }
684 }
685
686 if (hole && seq_lt (sb->high_rxt, hole->start))
687 sb->high_rxt = hole->start;
688
689 return hole;
690}
691
692void
Florin Coras3eb50622017-07-13 01:24:57 -0400693scoreboard_init_high_rxt (sack_scoreboard_t * sb, u32 seq)
Florin Coras93992a92017-05-24 18:03:56 -0700694{
695 sack_scoreboard_hole_t *hole;
696 hole = scoreboard_first_hole (sb);
Florin Coras3eb50622017-07-13 01:24:57 -0400697 if (hole)
698 {
699 seq = seq_gt (seq, hole->start) ? seq : hole->start;
700 sb->cur_rxt_hole = sb->head;
701 }
702 sb->high_rxt = seq;
703}
704
705/**
706 * Test that scoreboard is sane after recovery
707 *
708 * Returns 1 if scoreboard is empty or if first hole beyond
709 * snd_una.
710 */
711u8
712tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
713{
714 sack_scoreboard_hole_t *hole;
715 hole = scoreboard_first_hole (&tc->sack_sb);
716 return (!hole || seq_geq (hole->start, tc->snd_una));
Florin Coras93992a92017-05-24 18:03:56 -0700717}
718
719void
Dave Barach68b0fb02017-02-28 15:15:56 -0500720tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
721{
722 sack_scoreboard_t *sb = &tc->sack_sb;
723 sack_block_t *blk, tmp;
Florin Corasf03a59a2017-06-09 21:07:32 -0700724 sack_scoreboard_hole_t *hole, *next_hole, *last_hole;
Florin Coras93992a92017-05-24 18:03:56 -0700725 u32 blk_index = 0, old_sacked_bytes, hole_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500726 int i, j;
727
Florin Coras6792ec02017-03-13 03:49:51 -0700728 sb->last_sacked_bytes = 0;
729 sb->snd_una_adv = 0;
730 old_sacked_bytes = sb->sacked_bytes;
Florin Coras93992a92017-05-24 18:03:56 -0700731 sb->last_bytes_delivered = 0;
Florin Coras6792ec02017-03-13 03:49:51 -0700732
Florin Coras93992a92017-05-24 18:03:56 -0700733 if (!tcp_opts_sack (&tc->rcv_opts)
734 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
Dave Barach68b0fb02017-02-28 15:15:56 -0500735 return;
736
737 /* Remove invalid blocks */
Florin Coras93992a92017-05-24 18:03:56 -0700738 blk = tc->rcv_opts.sacks;
739 while (blk < vec_end (tc->rcv_opts.sacks))
Florin Coras6792ec02017-03-13 03:49:51 -0700740 {
741 if (seq_lt (blk->start, blk->end)
742 && seq_gt (blk->start, tc->snd_una)
Florin Coras3eb50622017-07-13 01:24:57 -0400743 && seq_gt (blk->start, ack) && seq_leq (blk->end, tc->snd_una_max))
Florin Coras6792ec02017-03-13 03:49:51 -0700744 {
745 blk++;
746 continue;
747 }
Florin Coras93992a92017-05-24 18:03:56 -0700748 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
Florin Coras6792ec02017-03-13 03:49:51 -0700749 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500750
751 /* Add block for cumulative ack */
752 if (seq_gt (ack, tc->snd_una))
753 {
754 tmp.start = tc->snd_una;
755 tmp.end = ack;
Florin Coras93992a92017-05-24 18:03:56 -0700756 vec_add1 (tc->rcv_opts.sacks, tmp);
Dave Barach68b0fb02017-02-28 15:15:56 -0500757 }
758
Florin Coras93992a92017-05-24 18:03:56 -0700759 if (vec_len (tc->rcv_opts.sacks) == 0)
Dave Barach68b0fb02017-02-28 15:15:56 -0500760 return;
761
Florin Coras3eb50622017-07-13 01:24:57 -0400762 tcp_scoreboard_trace_add (tc, ack);
763
Dave Barach68b0fb02017-02-28 15:15:56 -0500764 /* Make sure blocks are ordered */
Florin Coras93992a92017-05-24 18:03:56 -0700765 for (i = 0; i < vec_len (tc->rcv_opts.sacks); i++)
766 for (j = i + 1; j < vec_len (tc->rcv_opts.sacks); j++)
767 if (seq_lt (tc->rcv_opts.sacks[j].start, tc->rcv_opts.sacks[i].start))
Dave Barach68b0fb02017-02-28 15:15:56 -0500768 {
Florin Coras93992a92017-05-24 18:03:56 -0700769 tmp = tc->rcv_opts.sacks[i];
770 tc->rcv_opts.sacks[i] = tc->rcv_opts.sacks[j];
771 tc->rcv_opts.sacks[j] = tmp;
Dave Barach68b0fb02017-02-28 15:15:56 -0500772 }
773
Dave Barach68b0fb02017-02-28 15:15:56 -0500774 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
775 {
Florin Coras6792ec02017-03-13 03:49:51 -0700776 /* If no holes, insert the first that covers all outstanding bytes */
777 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
778 tc->snd_una, tc->snd_una_max);
779 sb->tail = scoreboard_hole_index (sb, last_hole);
Florin Coras93992a92017-05-24 18:03:56 -0700780 tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
781 sb->high_sacked = tmp.end;
Florin Coras6792ec02017-03-13 03:49:51 -0700782 }
783 else
784 {
785 /* If we have holes but snd_una_max is beyond the last hole, update
786 * last hole end */
Florin Coras93992a92017-05-24 18:03:56 -0700787 tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
Florin Coras6792ec02017-03-13 03:49:51 -0700788 last_hole = scoreboard_last_hole (sb);
Dave Barach2c25a622017-06-26 11:35:07 -0400789 if (seq_gt (tc->snd_una_max, last_hole->end))
790 {
791 if (seq_geq (last_hole->start, sb->high_sacked))
792 {
793 last_hole->end = tc->snd_una_max;
794 }
795 /* New hole after high sacked block */
796 else if (seq_lt (sb->high_sacked, tc->snd_una_max))
797 {
798 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
799 tc->snd_una_max);
800 }
801 }
802 /* Keep track of max byte sacked for when the last hole
Florin Corasf03a59a2017-06-09 21:07:32 -0700803 * is acked */
804 if (seq_gt (tmp.end, sb->high_sacked))
805 sb->high_sacked = tmp.end;
Dave Barach68b0fb02017-02-28 15:15:56 -0500806 }
807
808 /* Walk the holes with the SACK blocks */
809 hole = pool_elt_at_index (sb->holes, sb->head);
Florin Coras93992a92017-05-24 18:03:56 -0700810 while (hole && blk_index < vec_len (tc->rcv_opts.sacks))
Dave Barach68b0fb02017-02-28 15:15:56 -0500811 {
Florin Coras93992a92017-05-24 18:03:56 -0700812 blk = &tc->rcv_opts.sacks[blk_index];
Dave Barach68b0fb02017-02-28 15:15:56 -0500813 if (seq_leq (blk->start, hole->start))
814 {
815 /* Block covers hole. Remove hole */
816 if (seq_geq (blk->end, hole->end))
817 {
818 next_hole = scoreboard_next_hole (sb, hole);
819
Florin Corasf03a59a2017-06-09 21:07:32 -0700820 /* Byte accounting: snd_una needs to be advanced */
821 if (blk->end == ack)
Dave Barach68b0fb02017-02-28 15:15:56 -0500822 {
Florin Corasf03a59a2017-06-09 21:07:32 -0700823 if (next_hole)
Florin Coras06d11012017-05-17 14:21:51 -0700824 {
Florin Corasf03a59a2017-06-09 21:07:32 -0700825 if (seq_lt (ack, next_hole->start))
826 sb->snd_una_adv = next_hole->start - ack;
827 sb->last_bytes_delivered +=
828 next_hole->start - hole->end;
Florin Coras06d11012017-05-17 14:21:51 -0700829 }
Florin Coras3eb50622017-07-13 01:24:57 -0400830 else
Florin Coras06d11012017-05-17 14:21:51 -0700831 {
Dave Barach2c25a622017-06-26 11:35:07 -0400832 ASSERT (seq_geq (sb->high_sacked, ack));
Florin Coras93992a92017-05-24 18:03:56 -0700833 sb->snd_una_adv = sb->high_sacked - ack;
Florin Corasf03a59a2017-06-09 21:07:32 -0700834 sb->last_bytes_delivered += sb->high_sacked - hole->end;
Florin Coras06d11012017-05-17 14:21:51 -0700835 }
836 }
837
Dave Barach68b0fb02017-02-28 15:15:56 -0500838 scoreboard_remove_hole (sb, hole);
839 hole = next_hole;
840 }
Florin Coras6792ec02017-03-13 03:49:51 -0700841 /* Partial 'head' overlap */
Dave Barach68b0fb02017-02-28 15:15:56 -0500842 else
843 {
Florin Coras6792ec02017-03-13 03:49:51 -0700844 if (seq_gt (blk->end, hole->start))
845 {
Florin Coras6792ec02017-03-13 03:49:51 -0700846 hole->start = blk->end;
847 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500848 blk_index++;
849 }
850 }
851 else
852 {
853 /* Hole must be split */
Florin Coras6792ec02017-03-13 03:49:51 -0700854 if (seq_lt (blk->end, hole->end))
Dave Barach68b0fb02017-02-28 15:15:56 -0500855 {
Florin Coras6792ec02017-03-13 03:49:51 -0700856 hole_index = scoreboard_hole_index (sb, hole);
Florin Coras3eb50622017-07-13 01:24:57 -0400857 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
858 hole->end);
Florin Coras6792ec02017-03-13 03:49:51 -0700859
860 /* Pool might've moved */
861 hole = scoreboard_get_hole (sb, hole_index);
862 hole->end = blk->start;
Dave Barach68b0fb02017-02-28 15:15:56 -0500863 blk_index++;
Florin Coras3eb50622017-07-13 01:24:57 -0400864 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
Dave Barach68b0fb02017-02-28 15:15:56 -0500865 }
Florin Corasf03a59a2017-06-09 21:07:32 -0700866 else if (seq_lt (blk->start, hole->end))
Dave Barach68b0fb02017-02-28 15:15:56 -0500867 {
Florin Coras6792ec02017-03-13 03:49:51 -0700868 hole->end = blk->start;
Dave Barach68b0fb02017-02-28 15:15:56 -0500869 }
Florin Coras93992a92017-05-24 18:03:56 -0700870 hole = scoreboard_next_hole (sb, hole);
Dave Barach68b0fb02017-02-28 15:15:56 -0500871 }
872 }
Florin Coras6792ec02017-03-13 03:49:51 -0700873
Florin Corasf03a59a2017-06-09 21:07:32 -0700874 scoreboard_update_bytes (tc, sb);
875 sb->last_sacked_bytes = sb->sacked_bytes
876 - (old_sacked_bytes - sb->last_bytes_delivered);
Dave Barach2c25a622017-06-26 11:35:07 -0400877 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes);
Florin Corasf03a59a2017-06-09 21:07:32 -0700878 ASSERT (sb->sacked_bytes == 0
879 || sb->sacked_bytes < tc->snd_una_max - seq_max (tc->snd_una, ack));
880 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_una_max
881 - seq_max (tc->snd_una, ack));
Dave Barach2c25a622017-06-26 11:35:07 -0400882 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
883 || sb->holes[sb->head].start == ack + sb->snd_una_adv);
Dave Barach68b0fb02017-02-28 15:15:56 -0500884}
885
Florin Coras93992a92017-05-24 18:03:56 -0700886/**
887 * Try to update snd_wnd based on feedback received from peer.
Dave Barach68b0fb02017-02-28 15:15:56 -0500888 *
Florin Coras93992a92017-05-24 18:03:56 -0700889 * If successful, and new window is 'effectively' 0, activate persist
890 * timer.
891 */
Dave Barach68b0fb02017-02-28 15:15:56 -0500892static void
893tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
894{
Florin Coras93992a92017-05-24 18:03:56 -0700895 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
896 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
Florin Coras6792ec02017-03-13 03:49:51 -0700897 if (seq_lt (tc->snd_wl1, seq)
898 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500899 {
900 tc->snd_wnd = snd_wnd;
901 tc->snd_wl1 = seq;
902 tc->snd_wl2 = ack;
Florin Coras6792ec02017-03-13 03:49:51 -0700903 TCP_EVT_DBG (TCP_EVT_SND_WND, tc);
Florin Coras3e350af2017-03-30 02:54:28 -0700904
Florin Corasbb292f42017-05-19 09:49:19 -0700905 if (tc->snd_wnd < tc->snd_mss)
906 {
Florin Coras93992a92017-05-24 18:03:56 -0700907 /* Set persist timer if not set and we just got 0 wnd */
908 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
909 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
Florin Corasbb292f42017-05-19 09:49:19 -0700910 tcp_persist_timer_set (tc);
911 }
Florin Coras3e350af2017-03-30 02:54:28 -0700912 else
Florin Coras93992a92017-05-24 18:03:56 -0700913 {
914 tcp_persist_timer_reset (tc);
915 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
916 {
917 tc->rto_boff = 0;
918 tcp_update_rto (tc);
919 }
920 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500921 }
922}
923
Florin Coras6792ec02017-03-13 03:49:51 -0700924void
Florin Coras93992a92017-05-24 18:03:56 -0700925tcp_cc_init_congestion (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -0500926{
Florin Coras93992a92017-05-24 18:03:56 -0700927 tcp_fastrecovery_on (tc);
928 tc->snd_congestion = tc->snd_una_max;
Dave Barach68b0fb02017-02-28 15:15:56 -0500929 tc->cc_algo->congestion (tc);
Florin Coras6792ec02017-03-13 03:49:51 -0700930 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 4);
Dave Barach68b0fb02017-02-28 15:15:56 -0500931}
932
Florin Coras93992a92017-05-24 18:03:56 -0700933static void
934tcp_cc_recovery_exit (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -0500935{
Florin Coras93992a92017-05-24 18:03:56 -0700936 /* Deflate rto */
Florin Coras93992a92017-05-24 18:03:56 -0700937 tc->rto_boff = 0;
Florin Corasf1762d62017-09-24 19:43:08 -0400938 tcp_update_rto (tc);
Florin Coras93992a92017-05-24 18:03:56 -0700939 tc->snd_rxt_ts = 0;
Florin Coras84275e92017-09-26 12:30:40 -0400940 tc->snd_nxt = tc->snd_una_max;
Florin Coras93992a92017-05-24 18:03:56 -0700941 tcp_recovery_off (tc);
Florin Corasf1762d62017-09-24 19:43:08 -0400942 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 3);
Florin Coras93992a92017-05-24 18:03:56 -0700943}
Florin Coras3e350af2017-03-30 02:54:28 -0700944
Florin Coras93992a92017-05-24 18:03:56 -0700945void
946tcp_cc_fastrecovery_exit (tcp_connection_t * tc)
947{
Florin Coras6792ec02017-03-13 03:49:51 -0700948 tc->cc_algo->recovered (tc);
Florin Coras93992a92017-05-24 18:03:56 -0700949 tc->snd_rxt_bytes = 0;
Florin Coras6792ec02017-03-13 03:49:51 -0700950 tc->rcv_dupacks = 0;
Florin Coras84275e92017-09-26 12:30:40 -0400951 tc->snd_nxt = tc->snd_una_max;
Florin Coras93992a92017-05-24 18:03:56 -0700952 tcp_fastrecovery_off (tc);
953 tcp_fastrecovery_1_smss_off (tc);
Florin Corasf1762d62017-09-24 19:43:08 -0400954 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 3);
Dave Barach68b0fb02017-02-28 15:15:56 -0500955}
956
957static void
Florin Coras93992a92017-05-24 18:03:56 -0700958tcp_cc_congestion_undo (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -0500959{
Florin Coras93992a92017-05-24 18:03:56 -0700960 tc->cwnd = tc->prev_cwnd;
961 tc->ssthresh = tc->prev_ssthresh;
962 tc->snd_nxt = tc->snd_una_max;
963 tc->rcv_dupacks = 0;
964 if (tcp_in_recovery (tc))
965 tcp_cc_recovery_exit (tc);
966 ASSERT (tc->rto_boff == 0);
Florin Corasf1762d62017-09-24 19:43:08 -0400967 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 5);
Florin Coras93992a92017-05-24 18:03:56 -0700968 /* TODO extend for fastrecovery */
969}
Dave Barach68b0fb02017-02-28 15:15:56 -0500970
Florin Coras93992a92017-05-24 18:03:56 -0700971static u8
972tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
973{
Florin Corasf1762d62017-09-24 19:43:08 -0400974 return (tcp_in_recovery (tc) && tc->rto_boff == 1
Dave Barach2c25a622017-06-26 11:35:07 -0400975 && tc->snd_rxt_ts
Florin Coras93992a92017-05-24 18:03:56 -0700976 && tcp_opts_tstamp (&tc->rcv_opts)
977 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
978}
979
980int
981tcp_cc_recover (tcp_connection_t * tc)
982{
983 ASSERT (tcp_in_cong_recovery (tc));
984 if (tcp_cc_is_spurious_retransmit (tc))
Dave Barach68b0fb02017-02-28 15:15:56 -0500985 {
Florin Coras93992a92017-05-24 18:03:56 -0700986 tcp_cc_congestion_undo (tc);
987 return 1;
988 }
989
990 if (tcp_in_recovery (tc))
991 tcp_cc_recovery_exit (tc);
992 else if (tcp_in_fastrecovery (tc))
993 tcp_cc_fastrecovery_exit (tc);
994
995 ASSERT (tc->rto_boff == 0);
996 ASSERT (!tcp_in_cong_recovery (tc));
Florin Coras3eb50622017-07-13 01:24:57 -0400997 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
Florin Coras93992a92017-05-24 18:03:56 -0700998 return 0;
999}
1000
1001static void
1002tcp_cc_update (tcp_connection_t * tc, vlib_buffer_t * b)
1003{
Florin Coras3eb50622017-07-13 01:24:57 -04001004 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
Florin Coras93992a92017-05-24 18:03:56 -07001005
1006 /* Congestion avoidance */
1007 tc->cc_algo->rcv_ack (tc);
1008 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1009
1010 /* If a cumulative ack, make sure dupacks is 0 */
1011 tc->rcv_dupacks = 0;
1012
1013 /* When dupacks hits the threshold we only enter fast retransmit if
1014 * cumulative ack covers more than snd_congestion. Should snd_una
1015 * wrap this test may fail under otherwise valid circumstances.
1016 * Therefore, proactively update snd_congestion when wrap detected. */
1017 if (PREDICT_FALSE
1018 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1019 && seq_gt (tc->snd_congestion, tc->snd_una)))
1020 tc->snd_congestion = tc->snd_una - 1;
1021}
1022
1023static u8
1024tcp_should_fastrecover_sack (tcp_connection_t * tc)
1025{
1026 return (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss < tc->sack_sb.sacked_bytes;
1027}
1028
1029static u8
1030tcp_should_fastrecover (tcp_connection_t * tc)
1031{
1032 return (tc->rcv_dupacks == TCP_DUPACK_THRESHOLD
1033 || tcp_should_fastrecover_sack (tc));
1034}
1035
Florin Corasf03a59a2017-06-09 21:07:32 -07001036/**
1037 * One function to rule them all ... and in the darkness bind them
1038 */
Florin Coras93992a92017-05-24 18:03:56 -07001039static void
1040tcp_cc_handle_event (tcp_connection_t * tc, u32 is_dack)
1041{
Florin Corasf03a59a2017-06-09 21:07:32 -07001042 u32 rxt_delivered;
1043
Florin Coras93992a92017-05-24 18:03:56 -07001044 /*
1045 * Duplicate ACK. Check if we should enter fast recovery, or if already in
1046 * it account for the bytes that left the network.
1047 */
1048 if (is_dack)
1049 {
1050 ASSERT (tc->snd_una != tc->snd_una_max
1051 || tc->sack_sb.last_sacked_bytes);
Dave Barach2c25a622017-06-26 11:35:07 -04001052
Florin Coras93992a92017-05-24 18:03:56 -07001053 tc->rcv_dupacks++;
1054
1055 if (tc->rcv_dupacks > TCP_DUPACK_THRESHOLD && !tc->bytes_acked)
Dave Barach68b0fb02017-02-28 15:15:56 -05001056 {
Florin Coras93992a92017-05-24 18:03:56 -07001057 ASSERT (tcp_in_fastrecovery (tc));
1058 /* Pure duplicate ack. If some data got acked, it's handled lower */
1059 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
1060 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001061 }
Florin Coras93992a92017-05-24 18:03:56 -07001062 else if (tcp_should_fastrecover (tc))
Dave Barach68b0fb02017-02-28 15:15:56 -05001063 {
Florin Coras93992a92017-05-24 18:03:56 -07001064 /* Things are already bad */
1065 if (tcp_in_cong_recovery (tc))
Florin Coras6792ec02017-03-13 03:49:51 -07001066 {
Florin Coras93992a92017-05-24 18:03:56 -07001067 tc->rcv_dupacks = 0;
1068 goto partial_ack_test;
1069 }
1070
Dave Barach2c25a622017-06-26 11:35:07 -04001071 /* If of of the two conditions lower hold, reset dupacks because
1072 * we're probably after timeout (RFC6582 heuristics).
1073 * If Cumulative ack does not cover more than congestion threshold,
1074 * and:
1075 * 1) The following doesn't hold: The congestion window is greater
1076 * than SMSS bytes and the difference between highest_ack
1077 * and prev_highest_ack is at most 4*SMSS bytes
1078 * 2) Echoed timestamp in the last non-dup ack does not equal the
1079 * stored timestamp
Florin Coras93992a92017-05-24 18:03:56 -07001080 */
Dave Barach2c25a622017-06-26 11:35:07 -04001081 if (seq_leq (tc->snd_una, tc->snd_congestion)
1082 && ((!(tc->cwnd > tc->snd_mss
1083 && tc->bytes_acked <= 4 * tc->snd_mss))
1084 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
Florin Coras93992a92017-05-24 18:03:56 -07001085 {
1086 tc->rcv_dupacks = 0;
1087 return;
1088 }
1089
1090 tcp_cc_init_congestion (tc);
1091 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
1092
1093 /* The first segment MUST be retransmitted */
1094 tcp_retransmit_first_unacked (tc);
1095
1096 /* Post retransmit update cwnd to ssthresh and account for the
1097 * three segments that have left the network and should've been
1098 * buffered at the receiver XXX */
1099 tc->cwnd = tc->ssthresh + tc->rcv_dupacks * tc->snd_mss;
Dave Barach2c25a622017-06-26 11:35:07 -04001100 ASSERT (tc->cwnd >= tc->snd_mss);
Florin Coras93992a92017-05-24 18:03:56 -07001101
1102 /* If cwnd allows, send more data */
Florin Coras3eb50622017-07-13 01:24:57 -04001103 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Coras93992a92017-05-24 18:03:56 -07001104 {
Florin Coras3eb50622017-07-13 01:24:57 -04001105 scoreboard_init_high_rxt (&tc->sack_sb,
1106 tc->snd_una + tc->snd_mss);
Florin Coras93992a92017-05-24 18:03:56 -07001107 tcp_fast_retransmit_sack (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001108 }
1109 else
1110 {
Florin Coras93992a92017-05-24 18:03:56 -07001111 tcp_fast_retransmit_no_sack (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001112 }
Florin Coras93992a92017-05-24 18:03:56 -07001113
1114 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001115 }
Florin Coras93992a92017-05-24 18:03:56 -07001116 else if (!tc->bytes_acked
1117 || (tc->bytes_acked && !tcp_in_cong_recovery (tc)))
1118 {
1119 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
1120 return;
1121 }
1122 else
1123 goto partial_ack;
1124 }
1125
1126partial_ack_test:
1127
1128 if (!tc->bytes_acked)
1129 return;
1130
1131partial_ack:
1132 /*
1133 * Legitimate ACK. 1) See if we can exit recovery
1134 */
1135 /* XXX limit this only to first partial ack? */
1136 tcp_retransmit_timer_update (tc);
1137
1138 if (seq_geq (tc->snd_una, tc->snd_congestion))
1139 {
1140 /* If spurious return, we've already updated everything */
1141 if (tcp_cc_recover (tc))
Florin Corasf03a59a2017-06-09 21:07:32 -07001142 {
1143 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1144 return;
1145 }
Florin Coras93992a92017-05-24 18:03:56 -07001146
1147 tc->snd_nxt = tc->snd_una_max;
1148
1149 /* Treat as congestion avoidance ack */
1150 tc->cc_algo->rcv_ack (tc);
1151 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1152 return;
1153 }
1154
1155 /*
1156 * Legitimate ACK. 2) If PARTIAL ACK try to retransmit
1157 */
1158 TCP_EVT_DBG (TCP_EVT_CC_PACK, tc);
1159
1160 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1161 * reset dupacks to 0 */
1162 tc->rcv_dupacks = 0;
1163
1164 tcp_retransmit_first_unacked (tc);
1165
1166 /* Post RTO timeout don't try anything fancy */
1167 if (tcp_in_recovery (tc))
1168 return;
1169
1170 /* Remove retransmitted bytes that have been delivered */
Florin Corasf03a59a2017-06-09 21:07:32 -07001171 ASSERT (tc->bytes_acked + tc->sack_sb.snd_una_adv
Florin Corasb2215d62017-08-01 16:56:58 -07001172 >= tc->sack_sb.last_bytes_delivered
1173 || (tc->flags & TCP_CONN_FINSNT));
Florin Coras3eb50622017-07-13 01:24:57 -04001174
1175 if (seq_lt (tc->snd_una, tc->sack_sb.high_rxt))
Florin Coras93992a92017-05-24 18:03:56 -07001176 {
1177 /* If we have sacks and we haven't gotten an ack beyond high_rxt,
1178 * remove sacked bytes delivered */
Florin Coras3eb50622017-07-13 01:24:57 -04001179 rxt_delivered = tc->bytes_acked + tc->sack_sb.snd_una_adv
1180 - tc->sack_sb.last_bytes_delivered;
Florin Corasf03a59a2017-06-09 21:07:32 -07001181 ASSERT (tc->snd_rxt_bytes >= rxt_delivered);
1182 tc->snd_rxt_bytes -= rxt_delivered;
Dave Barach68b0fb02017-02-28 15:15:56 -05001183 }
1184 else
1185 {
Florin Coras93992a92017-05-24 18:03:56 -07001186 /* Either all retransmitted holes have been acked, or we're
1187 * "in the blind" and retransmitting segment by segment */
1188 tc->snd_rxt_bytes = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001189 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001190
Florin Coras93992a92017-05-24 18:03:56 -07001191 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_PARTIALACK);
Dave Barach68b0fb02017-02-28 15:15:56 -05001192
Florin Coras93992a92017-05-24 18:03:56 -07001193 /*
1194 * Since this was a partial ack, try to retransmit some more data
1195 */
1196 tcp_fast_retransmit (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -05001197}
1198
1199void
1200tcp_cc_init (tcp_connection_t * tc)
1201{
1202 tc->cc_algo = tcp_cc_algo_get (TCP_CC_NEWRENO);
1203 tc->cc_algo->init (tc);
1204}
1205
Florin Coras93992a92017-05-24 18:03:56 -07001206/**
1207 * Process incoming ACK
1208 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001209static int
1210tcp_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b,
1211 tcp_header_t * th, u32 * next, u32 * error)
1212{
Florin Coras93992a92017-05-24 18:03:56 -07001213 u32 prev_snd_wnd, prev_snd_una;
1214 u8 is_dack;
Dave Barach68b0fb02017-02-28 15:15:56 -05001215
Florin Corasf03a59a2017-06-09 21:07:32 -07001216 TCP_EVT_DBG (TCP_EVT_CC_STAT, tc);
1217
Florin Coras6792ec02017-03-13 03:49:51 -07001218 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
Florin Coras93992a92017-05-24 18:03:56 -07001219 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
Dave Barach68b0fb02017-02-28 15:15:56 -05001220 {
Florin Coras6792ec02017-03-13 03:49:51 -07001221 /* If we have outstanding data and this is within the window, accept it,
1222 * probably retransmit has timed out. Otherwise ACK segment and then
1223 * drop it */
1224 if (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max))
1225 {
1226 tcp_make_ack (tc, b);
1227 *next = tcp_next_output (tc->c_is_ip4);
1228 *error = TCP_ERROR_ACK_INVALID;
1229 TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 0,
1230 vnet_buffer (b)->tcp.ack_number);
1231 return -1;
1232 }
1233
Florin Coras6792ec02017-03-13 03:49:51 -07001234 TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 2,
1235 vnet_buffer (b)->tcp.ack_number);
Florin Coras3e350af2017-03-30 02:54:28 -07001236
1237 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1238 *error = TCP_ERROR_ACK_FUTURE;
Dave Barach68b0fb02017-02-28 15:15:56 -05001239 }
1240
Florin Coras6792ec02017-03-13 03:49:51 -07001241 /* If old ACK, probably it's an old dupack */
Florin Coras93992a92017-05-24 18:03:56 -07001242 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
Dave Barach68b0fb02017-02-28 15:15:56 -05001243 {
1244 *error = TCP_ERROR_ACK_OLD;
Florin Coras6792ec02017-03-13 03:49:51 -07001245 TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 1,
1246 vnet_buffer (b)->tcp.ack_number);
1247 if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1248 {
1249 TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc);
Florin Coras93992a92017-05-24 18:03:56 -07001250 tcp_cc_handle_event (tc, 1);
Florin Coras6792ec02017-03-13 03:49:51 -07001251 }
Florin Corasc28764f2017-04-26 00:08:42 -07001252 /* Don't drop yet */
1253 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001254 }
1255
Florin Coras93992a92017-05-24 18:03:56 -07001256 /*
1257 * Looks okay, process feedback
1258 */
1259
Florin Coras93992a92017-05-24 18:03:56 -07001260 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05001261 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1262
Florin Coras93992a92017-05-24 18:03:56 -07001263 prev_snd_wnd = tc->snd_wnd;
1264 prev_snd_una = tc->snd_una;
1265 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1266 vnet_buffer (b)->tcp.ack_number,
1267 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1268 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1269 tc->snd_una = vnet_buffer (b)->tcp.ack_number + tc->sack_sb.snd_una_adv;
1270 tcp_validate_txf_size (tc, tc->bytes_acked);
Dave Barach68b0fb02017-02-28 15:15:56 -05001271
Florin Coras93992a92017-05-24 18:03:56 -07001272 if (tc->bytes_acked)
1273 tcp_dequeue_acked (tc, vnet_buffer (b)->tcp.ack_number);
1274
Florin Coras6534b7a2017-07-18 05:38:03 -04001275 TCP_EVT_DBG (TCP_EVT_ACK_RCVD, tc);
1276
Florin Coras93992a92017-05-24 18:03:56 -07001277 /*
1278 * Check if we have congestion event
1279 */
1280
1281 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
Dave Barach68b0fb02017-02-28 15:15:56 -05001282 {
Florin Coras93992a92017-05-24 18:03:56 -07001283 tcp_cc_handle_event (tc, is_dack);
Florin Corasb2215d62017-08-01 16:56:58 -07001284 if (!tcp_in_cong_recovery (tc))
1285 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001286 *error = TCP_ERROR_ACK_DUP;
Florin Coras93992a92017-05-24 18:03:56 -07001287 TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc, 1);
1288 return vnet_buffer (b)->tcp.data_len ? 0 : -1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001289 }
1290
Florin Coras6792ec02017-03-13 03:49:51 -07001291 /*
Florin Coras93992a92017-05-24 18:03:56 -07001292 * Update congestion control (slow start/congestion avoidance)
Florin Coras6792ec02017-03-13 03:49:51 -07001293 */
Florin Coras93992a92017-05-24 18:03:56 -07001294 tcp_cc_update (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -05001295
1296 return 0;
1297}
1298
Florin Coras3eb50622017-07-13 01:24:57 -04001299static u8
1300tcp_sack_vector_is_sane (sack_block_t * sacks)
1301{
1302 int i;
1303 for (i = 1; i < vec_len (sacks); i++)
1304 {
1305 if (sacks[i - 1].end == sacks[i].start)
1306 return 0;
1307 }
1308 return 1;
1309}
1310
Dave Barach68b0fb02017-02-28 15:15:56 -05001311/**
1312 * Build SACK list as per RFC2018.
1313 *
1314 * Makes sure the first block contains the segment that generated the current
1315 * ACK and the following ones are the ones most recently reported in SACK
1316 * blocks.
1317 *
1318 * @param tc TCP connection for which the SACK list is updated
1319 * @param start Start sequence number of the newest SACK block
1320 * @param end End sequence of the newest SACK block
1321 */
Florin Coras45d34962017-04-25 00:05:27 -07001322void
Dave Barach68b0fb02017-02-28 15:15:56 -05001323tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1324{
Florin Coras45d34962017-04-25 00:05:27 -07001325 sack_block_t *new_list = 0, *block = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001326 int i;
Dave Barach68b0fb02017-02-28 15:15:56 -05001327
1328 /* If the first segment is ooo add it to the list. Last write might've moved
1329 * rcv_nxt over the first segment. */
1330 if (seq_lt (tc->rcv_nxt, start))
1331 {
Florin Coras45d34962017-04-25 00:05:27 -07001332 vec_add2 (new_list, block, 1);
1333 block->start = start;
1334 block->end = end;
Dave Barach68b0fb02017-02-28 15:15:56 -05001335 }
1336
1337 /* Find the blocks still worth keeping. */
1338 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1339 {
Florin Coras45d34962017-04-25 00:05:27 -07001340 /* Discard if rcv_nxt advanced beyond current block */
1341 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
Dave Barach68b0fb02017-02-28 15:15:56 -05001342 continue;
1343
Florin Coras45d34962017-04-25 00:05:27 -07001344 /* Merge or drop if segment overlapped by the new segment */
1345 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1346 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1347 {
1348 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1349 new_list[0].start = tc->snd_sacks[i].start;
1350 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1351 new_list[0].end = tc->snd_sacks[i].end;
1352 continue;
1353 }
1354
1355 /* Save to new SACK list if we have space. */
1356 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1357 {
1358 vec_add1 (new_list, tc->snd_sacks[i]);
1359 }
Florin Corasf03a59a2017-06-09 21:07:32 -07001360 else
1361 {
1362 clib_warning ("sack discarded");
1363 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001364 }
1365
Florin Coras45d34962017-04-25 00:05:27 -07001366 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
Florin Coras6792ec02017-03-13 03:49:51 -07001367
Dave Barach68b0fb02017-02-28 15:15:56 -05001368 /* Replace old vector with new one */
1369 vec_free (tc->snd_sacks);
1370 tc->snd_sacks = new_list;
Florin Coras3eb50622017-07-13 01:24:57 -04001371
1372 /* Segments should not 'touch' */
1373 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
Dave Barach68b0fb02017-02-28 15:15:56 -05001374}
1375
1376/** Enqueue data for delivery to application */
Florin Coras6792ec02017-03-13 03:49:51 -07001377always_inline int
Dave Barach68b0fb02017-02-28 15:15:56 -05001378tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1379 u16 data_len)
1380{
Florin Coras1f152cd2017-08-18 19:28:03 -07001381 int written, error = TCP_ERROR_ENQUEUED;
Dave Barach68b0fb02017-02-28 15:15:56 -05001382
Dave Barach2c25a622017-06-26 11:35:07 -04001383 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1384
Dave Barach68b0fb02017-02-28 15:15:56 -05001385 /* Pure ACK. Update rcv_nxt and be done. */
1386 if (PREDICT_FALSE (data_len == 0))
1387 {
Dave Barach68b0fb02017-02-28 15:15:56 -05001388 return TCP_ERROR_PURE_ACK;
1389 }
1390
Florin Corasf6d68ed2017-05-07 19:12:02 -07001391 written = stream_session_enqueue_data (&tc->connection, b, 0,
1392 1 /* queue event */ , 1);
Dave Barach68b0fb02017-02-28 15:15:56 -05001393
Florin Coras6792ec02017-03-13 03:49:51 -07001394 TCP_EVT_DBG (TCP_EVT_INPUT, tc, 0, data_len, written);
1395
Dave Barach68b0fb02017-02-28 15:15:56 -05001396 /* Update rcv_nxt */
1397 if (PREDICT_TRUE (written == data_len))
1398 {
Florin Coras1f152cd2017-08-18 19:28:03 -07001399 tc->rcv_nxt += written;
Dave Barach68b0fb02017-02-28 15:15:56 -05001400 }
1401 /* If more data written than expected, account for out-of-order bytes. */
1402 else if (written > data_len)
1403 {
Florin Coras1f152cd2017-08-18 19:28:03 -07001404 tc->rcv_nxt += written;
Dave Barach68b0fb02017-02-28 15:15:56 -05001405
1406 /* Send ACK confirming the update */
1407 tc->flags |= TCP_CONN_SNDACK;
Florin Coras6792ec02017-03-13 03:49:51 -07001408 }
1409 else if (written > 0)
1410 {
1411 /* We've written something but FIFO is probably full now */
1412 tc->rcv_nxt += written;
Dave Barach68b0fb02017-02-28 15:15:56 -05001413
Florin Coras6792ec02017-03-13 03:49:51 -07001414 /* Depending on how fast the app is, all remaining buffers in burst will
Florin Coras3e350af2017-03-30 02:54:28 -07001415 * not be enqueued. Inform peer */
1416 tc->flags |= TCP_CONN_SNDACK;
1417
Florin Coras1f152cd2017-08-18 19:28:03 -07001418 error = TCP_ERROR_PARTIALLY_ENQUEUED;
Dave Barach68b0fb02017-02-28 15:15:56 -05001419 }
1420 else
1421 {
Florin Coras3e350af2017-03-30 02:54:28 -07001422 tc->flags |= TCP_CONN_SNDACK;
Dave Barach68b0fb02017-02-28 15:15:56 -05001423 return TCP_ERROR_FIFO_FULL;
1424 }
1425
Florin Coras6792ec02017-03-13 03:49:51 -07001426 /* Update SACK list if need be */
Florin Coras93992a92017-05-24 18:03:56 -07001427 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Coras6792ec02017-03-13 03:49:51 -07001428 {
1429 /* Remove SACK blocks that have been delivered */
1430 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1431 }
1432
Florin Coras1f152cd2017-08-18 19:28:03 -07001433 return error;
Dave Barach68b0fb02017-02-28 15:15:56 -05001434}
1435
1436/** Enqueue out-of-order data */
Florin Coras6792ec02017-03-13 03:49:51 -07001437always_inline int
Dave Barach68b0fb02017-02-28 15:15:56 -05001438tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1439 u16 data_len)
1440{
1441 stream_session_t *s0;
Florin Coras3eb50622017-07-13 01:24:57 -04001442 int rv, offset;
Florin Coras6792ec02017-03-13 03:49:51 -07001443
Florin Corasf03a59a2017-06-09 21:07:32 -07001444 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1445
Florin Coras6792ec02017-03-13 03:49:51 -07001446 /* Pure ACK. Do nothing */
1447 if (PREDICT_FALSE (data_len == 0))
1448 {
1449 return TCP_ERROR_PURE_ACK;
1450 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001451
Florin Corasf03a59a2017-06-09 21:07:32 -07001452 /* Enqueue out-of-order data with relative offset */
Florin Corasf6d68ed2017-05-07 19:12:02 -07001453 rv = stream_session_enqueue_data (&tc->connection, b,
Florin Corasf03a59a2017-06-09 21:07:32 -07001454 vnet_buffer (b)->tcp.seq_number -
1455 tc->rcv_nxt, 0 /* queue event */ , 0);
Florin Coras6792ec02017-03-13 03:49:51 -07001456
1457 /* Nothing written */
1458 if (rv)
1459 {
1460 TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, 0);
1461 return TCP_ERROR_FIFO_FULL;
1462 }
1463
1464 TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, data_len);
Dave Barach68b0fb02017-02-28 15:15:56 -05001465
1466 /* Update SACK list if in use */
Florin Coras93992a92017-05-24 18:03:56 -07001467 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05001468 {
1469 ooo_segment_t *newest;
1470 u32 start, end;
1471
Florin Corasf6d68ed2017-05-07 19:12:02 -07001472 s0 = stream_session_get (tc->c_s_index, tc->c_thread_index);
1473
Dave Barach68b0fb02017-02-28 15:15:56 -05001474 /* Get the newest segment from the fifo */
1475 newest = svm_fifo_newest_ooo_segment (s0->server_rx_fifo);
Florin Corasf03a59a2017-06-09 21:07:32 -07001476 if (newest)
1477 {
Florin Coras3eb50622017-07-13 01:24:57 -04001478 offset = ooo_segment_offset (s0->server_rx_fifo, newest);
1479 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1480 start = tc->rcv_nxt + offset;
Florin Corasf03a59a2017-06-09 21:07:32 -07001481 end = start + ooo_segment_length (s0->server_rx_fifo, newest);
1482 tcp_update_sack_list (tc, start, end);
Florin Coras3eb50622017-07-13 01:24:57 -04001483 svm_fifo_newest_ooo_segment_reset (s0->server_rx_fifo);
Florin Corasf03a59a2017-06-09 21:07:32 -07001484 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001485 }
1486
1487 return TCP_ERROR_ENQUEUED;
1488}
1489
1490/**
Florin Coras6792ec02017-03-13 03:49:51 -07001491 * Check if ACK could be delayed. If ack can be delayed, it should return
1492 * true for a full frame. If we're always acking return 0.
Dave Barach68b0fb02017-02-28 15:15:56 -05001493 */
1494always_inline int
1495tcp_can_delack (tcp_connection_t * tc)
1496{
Florin Coras6792ec02017-03-13 03:49:51 -07001497 /* Send ack if ... */
1498 if (TCP_ALWAYS_ACK
1499 /* just sent a rcv wnd 0 */
1500 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0
1501 /* constrained to send ack */
1502 || (tc->flags & TCP_CONN_SNDACK) != 0
1503 /* we're almost out of tx wnd */
Florin Corasf03a59a2017-06-09 21:07:32 -07001504 || tcp_available_snd_space (tc) < 4 * tc->snd_mss)
Florin Coras6792ec02017-03-13 03:49:51 -07001505 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001506
Florin Coras6792ec02017-03-13 03:49:51 -07001507 return 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001508}
1509
1510static int
Florin Corasb2215d62017-08-01 16:56:58 -07001511tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1512{
Florin Coras1f152cd2017-08-18 19:28:03 -07001513 u32 discard, first = b->current_length;
Florin Corasb2215d62017-08-01 16:56:58 -07001514 vlib_main_t *vm = vlib_get_main ();
1515
Florin Coras1f152cd2017-08-18 19:28:03 -07001516 /* Handle multi-buffer segments */
Florin Corasb2215d62017-08-01 16:56:58 -07001517 if (n_bytes_to_drop > b->current_length)
1518 {
1519 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1520 return -1;
1521 do
1522 {
1523 discard = clib_min (n_bytes_to_drop, b->current_length);
1524 vlib_buffer_advance (b, discard);
1525 b = vlib_get_buffer (vm, b->next_buffer);
1526 n_bytes_to_drop -= discard;
1527 }
1528 while (n_bytes_to_drop);
Florin Coras1f152cd2017-08-18 19:28:03 -07001529 if (n_bytes_to_drop > first)
1530 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
Florin Corasb2215d62017-08-01 16:56:58 -07001531 }
Florin Coras1f152cd2017-08-18 19:28:03 -07001532 else
1533 vlib_buffer_advance (b, n_bytes_to_drop);
1534 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
Florin Corasb2215d62017-08-01 16:56:58 -07001535 return 0;
1536}
1537
1538static int
Dave Barach68b0fb02017-02-28 15:15:56 -05001539tcp_segment_rcv (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b,
Florin Coras6534b7a2017-07-18 05:38:03 -04001540 u32 * next0)
Dave Barach68b0fb02017-02-28 15:15:56 -05001541{
Florin Coras6534b7a2017-07-18 05:38:03 -04001542 u32 error = 0, n_bytes_to_drop, n_data_bytes;
1543
1544 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1545 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1546 ASSERT (n_data_bytes);
Dave Barach68b0fb02017-02-28 15:15:56 -05001547
1548 /* Handle out-of-order data */
1549 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1550 {
Florin Coras6792ec02017-03-13 03:49:51 -07001551 /* Old sequence numbers allowed through because they overlapped
1552 * the rx window */
1553 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
Dave Barach68b0fb02017-02-28 15:15:56 -05001554 {
Florin Coras6792ec02017-03-13 03:49:51 -07001555 error = TCP_ERROR_SEGMENT_OLD;
1556 *next0 = TCP_NEXT_DROP;
Florin Corasdb84e572017-05-09 18:54:52 -07001557
Dave Barach259cdae2017-05-15 16:27:05 -04001558 /* Completely in the past (possible retransmit) */
Florin Corasf03a59a2017-06-09 21:07:32 -07001559 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
Florin Coras6534b7a2017-07-18 05:38:03 -04001560 {
1561 /* Ack retransmissions since we may not have any data to send */
1562 tcp_make_ack (tc, b);
1563 *next0 = tcp_next_output (tc->c_is_ip4);
1564 goto done;
1565 }
Dave Barach259cdae2017-05-15 16:27:05 -04001566
Florin Corasdb84e572017-05-09 18:54:52 -07001567 /* Chop off the bytes in the past */
1568 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1569 n_data_bytes -= n_bytes_to_drop;
Dave Barach2c25a622017-06-26 11:35:07 -04001570 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
Florin Corasb2215d62017-08-01 16:56:58 -07001571 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1572 goto done;
Florin Corasdb84e572017-05-09 18:54:52 -07001573
1574 goto in_order;
Dave Barach68b0fb02017-02-28 15:15:56 -05001575 }
1576
Florin Coras6792ec02017-03-13 03:49:51 -07001577 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1578
1579 /* N.B. Should not filter burst of dupacks. Two issues 1) dupacks open
1580 * cwnd on remote peer when congested 2) acks leaving should have the
1581 * latest rcv_wnd since the burst may eaten up all of it, so only the
1582 * old ones could be filtered.
1583 */
1584
1585 /* RFC2581: Send DUPACK for fast retransmit */
1586 tcp_make_ack (tc, b);
1587 *next0 = tcp_next_output (tc->c_is_ip4);
1588
1589 /* Mark as DUPACK. We may filter these in output if
1590 * the burst fills the holes. */
1591 if (n_data_bytes)
1592 vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_DUPACK;
1593
1594 TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc);
Dave Barach68b0fb02017-02-28 15:15:56 -05001595 goto done;
1596 }
1597
Florin Corasdb84e572017-05-09 18:54:52 -07001598in_order:
1599
Dave Barach68b0fb02017-02-28 15:15:56 -05001600 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1601 * segments can be enqueued after fifo tail offset changes. */
1602 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1603
1604 /* Check if ACK can be delayed */
Florin Coras3e350af2017-03-30 02:54:28 -07001605 if (tcp_can_delack (tc))
Dave Barach68b0fb02017-02-28 15:15:56 -05001606 {
Florin Coras6792ec02017-03-13 03:49:51 -07001607 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1608 tcp_timer_set (tc, TCP_TIMER_DELACK, TCP_DELACK_TIME);
Florin Coras3e350af2017-03-30 02:54:28 -07001609 goto done;
Dave Barach68b0fb02017-02-28 15:15:56 -05001610 }
1611
Florin Coras3e350af2017-03-30 02:54:28 -07001612 *next0 = tcp_next_output (tc->c_is_ip4);
1613 tcp_make_ack (tc, b);
1614
Dave Barach68b0fb02017-02-28 15:15:56 -05001615done:
1616 return error;
1617}
1618
Clement Durand6cf260c2017-04-13 13:27:04 +02001619typedef struct
1620{
1621 tcp_header_t tcp_header;
1622 tcp_connection_t tcp_connection;
1623} tcp_rx_trace_t;
1624
1625u8 *
1626format_tcp_rx_trace (u8 * s, va_list * args)
1627{
1628 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1629 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1630 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1631 uword indent = format_get_indent (s);
1632
1633 s = format (s, "%U\n%U%U",
1634 format_tcp_header, &t->tcp_header, 128,
1635 format_white_space, indent,
Florin Corasbb292f42017-05-19 09:49:19 -07001636 format_tcp_connection, &t->tcp_connection, 1);
Clement Durand6cf260c2017-04-13 13:27:04 +02001637
1638 return s;
1639}
1640
1641u8 *
1642format_tcp_rx_trace_short (u8 * s, va_list * args)
1643{
1644 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1645 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1646 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1647
1648 s = format (s, "%d -> %d (%U)",
1649 clib_net_to_host_u16 (t->tcp_header.src_port),
1650 clib_net_to_host_u16 (t->tcp_header.dst_port), format_tcp_state,
Florin Corasbb292f42017-05-19 09:49:19 -07001651 t->tcp_connection.state);
Clement Durand6cf260c2017-04-13 13:27:04 +02001652
1653 return s;
1654}
1655
Florin Coras82b13a82017-04-25 11:58:06 -07001656void
1657tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1658 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1659{
1660 if (tc0)
1661 {
1662 clib_memcpy (&t0->tcp_connection, tc0, sizeof (t0->tcp_connection));
1663 }
1664 else
1665 {
1666 th0 = tcp_buffer_hdr (b0);
1667 }
1668 clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header));
1669}
1670
Florin Coras6792ec02017-03-13 03:49:51 -07001671always_inline void
1672tcp_established_inc_counter (vlib_main_t * vm, u8 is_ip4, u8 evt, u8 val)
Dave Barach68b0fb02017-02-28 15:15:56 -05001673{
Florin Coras6792ec02017-03-13 03:49:51 -07001674 if (PREDICT_TRUE (!val))
1675 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001676
Florin Coras6792ec02017-03-13 03:49:51 -07001677 if (is_ip4)
1678 vlib_node_increment_counter (vm, tcp4_established_node.index, evt, val);
1679 else
1680 vlib_node_increment_counter (vm, tcp6_established_node.index, evt, val);
Dave Barach68b0fb02017-02-28 15:15:56 -05001681}
1682
1683always_inline uword
1684tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1685 vlib_frame_t * from_frame, int is_ip4)
1686{
1687 u32 n_left_from, next_index, *from, *to_next;
Damjan Marion586afd72017-04-05 19:18:20 +02001688 u32 my_thread_index = vm->thread_index, errors = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001689 tcp_main_t *tm = vnet_get_tcp_main ();
Dave Barach1f75cfd2017-04-14 16:46:44 -04001690 u8 is_fin = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001691
1692 from = vlib_frame_vector_args (from_frame);
1693 n_left_from = from_frame->n_vectors;
1694
1695 next_index = node->cached_next_index;
1696
1697 while (n_left_from > 0)
1698 {
1699 u32 n_left_to_next;
1700
1701 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
Dave Barach68b0fb02017-02-28 15:15:56 -05001702 while (n_left_from > 0 && n_left_to_next > 0)
1703 {
1704 u32 bi0;
1705 vlib_buffer_t *b0;
1706 tcp_header_t *th0 = 0;
1707 tcp_connection_t *tc0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001708 u32 next0 = TCP_ESTABLISHED_NEXT_DROP, error0 = TCP_ERROR_ENQUEUED;
1709
1710 bi0 = from[0];
1711 to_next[0] = bi0;
1712 from += 1;
1713 to_next += 1;
1714 n_left_from -= 1;
1715 n_left_to_next -= 1;
1716
1717 b0 = vlib_get_buffer (vm, bi0);
1718 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
1719 my_thread_index);
1720
Florin Corasd79b41e2017-03-04 05:37:52 -08001721 if (PREDICT_FALSE (tc0 == 0))
1722 {
1723 error0 = TCP_ERROR_INVALID_CONNECTION;
Florin Coras6792ec02017-03-13 03:49:51 -07001724 goto done;
Florin Corasd79b41e2017-03-04 05:37:52 -08001725 }
1726
Florin Coras82b13a82017-04-25 11:58:06 -07001727 th0 = tcp_buffer_hdr (b0);
Florin Coras6534b7a2017-07-18 05:38:03 -04001728 /* N.B. buffer is rewritten if segment is ooo. Thus, th0 becomes a
1729 * dangling reference. */
1730 is_fin = tcp_is_fin (th0);
Dave Barach1f75cfd2017-04-14 16:46:44 -04001731
Dave Barach68b0fb02017-02-28 15:15:56 -05001732 /* SYNs, FINs and data consume sequence numbers */
1733 vnet_buffer (b0)->tcp.seq_end = vnet_buffer (b0)->tcp.seq_number
Florin Coras82b13a82017-04-25 11:58:06 -07001734 + tcp_is_syn (th0) + is_fin + vnet_buffer (b0)->tcp.data_len;
Dave Barach68b0fb02017-02-28 15:15:56 -05001735
1736 /* TODO header prediction fast path */
1737
1738 /* 1-4: check SEQ, RST, SYN */
1739 if (PREDICT_FALSE (tcp_segment_validate (vm, tc0, b0, th0, &next0)))
1740 {
1741 error0 = TCP_ERROR_SEGMENT_INVALID;
Florin Coras6792ec02017-03-13 03:49:51 -07001742 TCP_EVT_DBG (TCP_EVT_SEG_INVALID, tc0,
1743 vnet_buffer (b0)->tcp.seq_number,
1744 vnet_buffer (b0)->tcp.seq_end);
1745 goto done;
Dave Barach68b0fb02017-02-28 15:15:56 -05001746 }
1747
1748 /* 5: check the ACK field */
1749 if (tcp_rcv_ack (tc0, b0, th0, &next0, &error0))
Florin Coras6534b7a2017-07-18 05:38:03 -04001750 goto done;
Dave Barach68b0fb02017-02-28 15:15:56 -05001751
1752 /* 6: check the URG bit TODO */
1753
1754 /* 7: process the segment text */
Florin Coras6534b7a2017-07-18 05:38:03 -04001755 if (vnet_buffer (b0)->tcp.data_len)
1756 error0 = tcp_segment_rcv (tm, tc0, b0, &next0);
Dave Barach1f75cfd2017-04-14 16:46:44 -04001757
Dave Barach68b0fb02017-02-28 15:15:56 -05001758 /* 8: check the FIN bit */
Florin Coras6534b7a2017-07-18 05:38:03 -04001759 if (PREDICT_FALSE (is_fin))
Dave Barach68b0fb02017-02-28 15:15:56 -05001760 {
Florin Coras9d063042017-09-14 03:08:00 -04001761 /* Enter CLOSE-WAIT and notify session. To avoid lingering
Florin Corasd79b41e2017-03-04 05:37:52 -08001762 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
Florin Coras9d063042017-09-14 03:08:00 -04001763 /* Account for the FIN if nothing else was received */
Florin Coras68810622017-07-24 17:40:28 -07001764 if (vnet_buffer (b0)->tcp.data_len == 0)
Florin Coras9d063042017-09-14 03:08:00 -04001765 tc0->rcv_nxt += 1;
1766 tcp_make_ack (tc0, b0);
1767 next0 = tcp_next_output (tc0->c_is_ip4);
1768 tc0->state = TCP_STATE_CLOSE_WAIT;
Dave Barach68b0fb02017-02-28 15:15:56 -05001769 stream_session_disconnect_notify (&tc0->connection);
Florin Coras68810622017-07-24 17:40:28 -07001770 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
Florin Coras9d063042017-09-14 03:08:00 -04001771 TCP_EVT_DBG (TCP_EVT_FIN_RCVD, tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05001772 }
1773
Florin Coras6792ec02017-03-13 03:49:51 -07001774 done:
Dave Barach68b0fb02017-02-28 15:15:56 -05001775 b0->error = node->errors[error0];
1776 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
1777 {
Florin Coras82b13a82017-04-25 11:58:06 -07001778 tcp_rx_trace_t *t0 =
1779 vlib_add_trace (vm, node, b0, sizeof (*t0));
1780 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05001781 }
1782
1783 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1784 n_left_to_next, bi0, next0);
1785 }
1786
1787 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1788 }
1789
1790 errors = session_manager_flush_enqueue_events (my_thread_index);
Florin Coras6792ec02017-03-13 03:49:51 -07001791 tcp_established_inc_counter (vm, is_ip4, TCP_ERROR_EVENT_FIFO_FULL, errors);
Florin Coras66b11312017-07-31 17:18:03 -07001792 tcp_flush_frame_to_output (vm, my_thread_index, is_ip4);
1793
Dave Barach68b0fb02017-02-28 15:15:56 -05001794 return from_frame->n_vectors;
1795}
1796
1797static uword
1798tcp4_established (vlib_main_t * vm, vlib_node_runtime_t * node,
1799 vlib_frame_t * from_frame)
1800{
1801 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
1802}
1803
1804static uword
1805tcp6_established (vlib_main_t * vm, vlib_node_runtime_t * node,
1806 vlib_frame_t * from_frame)
1807{
1808 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
1809}
1810
1811/* *INDENT-OFF* */
1812VLIB_REGISTER_NODE (tcp4_established_node) =
1813{
1814 .function = tcp4_established,
1815 .name = "tcp4-established",
1816 /* Takes a vector of packets. */
1817 .vector_size = sizeof (u32),
Florin Corase69f4952017-03-07 10:06:24 -08001818 .n_errors = TCP_N_ERROR,
1819 .error_strings = tcp_error_strings,
Dave Barach68b0fb02017-02-28 15:15:56 -05001820 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1821 .next_nodes =
1822 {
1823#define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1824 foreach_tcp_state_next
1825#undef _
1826 },
Clement Durand6cf260c2017-04-13 13:27:04 +02001827 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05001828};
1829/* *INDENT-ON* */
1830
1831VLIB_NODE_FUNCTION_MULTIARCH (tcp4_established_node, tcp4_established);
1832
1833/* *INDENT-OFF* */
1834VLIB_REGISTER_NODE (tcp6_established_node) =
1835{
1836 .function = tcp6_established,
1837 .name = "tcp6-established",
1838 /* Takes a vector of packets. */
1839 .vector_size = sizeof (u32),
1840 .n_errors = TCP_N_ERROR,
1841 .error_strings = tcp_error_strings,
1842 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
1843 .next_nodes =
1844 {
1845#define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
1846 foreach_tcp_state_next
1847#undef _
1848 },
Clement Durand6cf260c2017-04-13 13:27:04 +02001849 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05001850};
1851/* *INDENT-ON* */
1852
1853
1854VLIB_NODE_FUNCTION_MULTIARCH (tcp6_established_node, tcp6_established);
1855
1856vlib_node_registration_t tcp4_syn_sent_node;
1857vlib_node_registration_t tcp6_syn_sent_node;
1858
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001859static u8
1860tcp_lookup_is_valid (tcp_connection_t * tc, tcp_header_t * hdr)
1861{
1862 transport_connection_t *tmp;
1863 if (!tc)
1864 return 1;
1865
1866 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
1867 && (tc->state == TCP_STATE_LISTEN
1868 || tc->c_rmt_port == hdr->src_port));
1869
1870 if (!is_valid)
1871 {
1872 if ((tmp =
1873 stream_session_half_open_lookup (&tc->c_lcl_ip, &tc->c_rmt_ip,
1874 tc->c_lcl_port, tc->c_rmt_port,
1875 tc->c_transport_proto)))
1876 {
1877 if (tmp->lcl_port == hdr->dst_port
1878 && tmp->rmt_port == hdr->src_port)
1879 {
1880 clib_warning ("half-open is valid!");
1881 }
1882 }
1883 }
1884 return is_valid;
1885}
1886
1887/**
1888 * Lookup transport connection
1889 */
1890static tcp_connection_t *
1891tcp_lookup_connection (vlib_buffer_t * b, u8 thread_index, u8 is_ip4)
1892{
1893 tcp_header_t *tcp;
1894 transport_connection_t *tconn;
1895 tcp_connection_t *tc;
1896 if (is_ip4)
1897 {
1898 ip4_header_t *ip4;
1899 ip4 = vlib_buffer_get_current (b);
1900 tcp = ip4_next_header (ip4);
1901 tconn = stream_session_lookup_transport_wt4 (&ip4->dst_address,
1902 &ip4->src_address,
1903 tcp->dst_port,
1904 tcp->src_port,
1905 SESSION_TYPE_IP4_TCP,
1906 thread_index);
1907 tc = tcp_get_connection_from_transport (tconn);
1908 ASSERT (tcp_lookup_is_valid (tc, tcp));
1909 }
1910 else
1911 {
1912 ip6_header_t *ip6;
1913 ip6 = vlib_buffer_get_current (b);
1914 tcp = ip6_next_header (ip6);
1915 tconn = stream_session_lookup_transport_wt6 (&ip6->dst_address,
1916 &ip6->src_address,
1917 tcp->dst_port,
1918 tcp->src_port,
1919 SESSION_TYPE_IP6_TCP,
1920 thread_index);
1921 tc = tcp_get_connection_from_transport (tconn);
1922 ASSERT (tcp_lookup_is_valid (tc, tcp));
1923 }
1924 return tc;
1925}
1926
Dave Barach68b0fb02017-02-28 15:15:56 -05001927always_inline uword
1928tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1929 vlib_frame_t * from_frame, int is_ip4)
1930{
1931 tcp_main_t *tm = vnet_get_tcp_main ();
1932 u32 n_left_from, next_index, *from, *to_next;
Damjan Marion586afd72017-04-05 19:18:20 +02001933 u32 my_thread_index = vm->thread_index, errors = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001934
1935 from = vlib_frame_vector_args (from_frame);
1936 n_left_from = from_frame->n_vectors;
1937
1938 next_index = node->cached_next_index;
1939
1940 while (n_left_from > 0)
1941 {
1942 u32 n_left_to_next;
1943
1944 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1945
1946 while (n_left_from > 0 && n_left_to_next > 0)
1947 {
1948 u32 bi0, ack0, seq0;
1949 vlib_buffer_t *b0;
Clement Durand6cf260c2017-04-13 13:27:04 +02001950 tcp_rx_trace_t *t0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001951 tcp_header_t *tcp0 = 0;
1952 tcp_connection_t *tc0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001953 tcp_connection_t *new_tc0;
1954 u32 next0 = TCP_SYN_SENT_NEXT_DROP, error0 = TCP_ERROR_ENQUEUED;
1955
1956 bi0 = from[0];
1957 to_next[0] = bi0;
1958 from += 1;
1959 to_next += 1;
1960 n_left_from -= 1;
1961 n_left_to_next -= 1;
1962
1963 b0 = vlib_get_buffer (vm, bi0);
1964 tc0 =
1965 tcp_half_open_connection_get (vnet_buffer (b0)->
1966 tcp.connection_index);
Dave Barachd84ba852017-08-22 17:56:46 -04001967 if (PREDICT_FALSE (tc0 == 0))
1968 {
1969 error0 = TCP_ERROR_INVALID_CONNECTION;
1970 goto drop;
1971 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001972
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001973 /* Half-open completed recently but the connection was't removed
1974 * yet by the owning thread */
1975 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
1976 {
1977 /* Make sure the connection actually exists */
1978 ASSERT (tcp_lookup_connection (b0, my_thread_index, is_ip4));
1979 goto drop;
1980 }
1981
Dave Barach68b0fb02017-02-28 15:15:56 -05001982 ack0 = vnet_buffer (b0)->tcp.ack_number;
1983 seq0 = vnet_buffer (b0)->tcp.seq_number;
Florin Coras82b13a82017-04-25 11:58:06 -07001984 tcp0 = tcp_buffer_hdr (b0);
Dave Barach68b0fb02017-02-28 15:15:56 -05001985
Florin Coras9d063042017-09-14 03:08:00 -04001986 /* Crude check to see if the connection handle does not match
1987 * the packet. Probably connection just switched to established */
1988 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
1989 || tcp0->src_port != tc0->c_rmt_port))
1990 goto drop;
1991
Dave Barach68b0fb02017-02-28 15:15:56 -05001992 if (PREDICT_FALSE
1993 (!tcp_ack (tcp0) && !tcp_rst (tcp0) && !tcp_syn (tcp0)))
1994 goto drop;
1995
1996 /* SYNs, FINs and data consume sequence numbers */
1997 vnet_buffer (b0)->tcp.seq_end = seq0 + tcp_is_syn (tcp0)
Florin Coras82b13a82017-04-25 11:58:06 -07001998 + tcp_is_fin (tcp0) + vnet_buffer (b0)->tcp.data_len;
Dave Barach68b0fb02017-02-28 15:15:56 -05001999
2000 /*
2001 * 1. check the ACK bit
2002 */
2003
2004 /*
2005 * If the ACK bit is set
2006 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2007 * the RST bit is set, if so drop the segment and return)
2008 * <SEQ=SEG.ACK><CTL=RST>
2009 * and discard the segment. Return.
2010 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2011 */
2012 if (tcp_ack (tcp0))
2013 {
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002014 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
Dave Barach68b0fb02017-02-28 15:15:56 -05002015 {
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002016 clib_warning ("ack not in rcv wnd");
Dave Barach68b0fb02017-02-28 15:15:56 -05002017 if (!tcp_rst (tcp0))
Florin Coras1f152cd2017-08-18 19:28:03 -07002018 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05002019 goto drop;
2020 }
2021
2022 /* Make sure ACK is valid */
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002023 if (seq_gt (tc0->snd_una, ack0))
2024 {
2025 clib_warning ("ack invalid");
2026 goto drop;
2027 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002028 }
2029
2030 /*
2031 * 2. check the RST bit
2032 */
2033
2034 if (tcp_rst (tcp0))
2035 {
2036 /* If ACK is acceptable, signal client that peer is not
2037 * willing to accept connection and drop connection*/
2038 if (tcp_ack (tcp0))
Florin Coras6534b7a2017-07-18 05:38:03 -04002039 tcp_connection_reset (tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002040 goto drop;
2041 }
2042
2043 /*
2044 * 3. check the security and precedence (skipped)
2045 */
2046
2047 /*
2048 * 4. check the SYN bit
2049 */
2050
2051 /* No SYN flag. Drop. */
2052 if (!tcp_syn (tcp0))
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002053 {
2054 clib_warning ("not synack");
2055 goto drop;
2056 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002057
Florin Coras6534b7a2017-07-18 05:38:03 -04002058 /* Parse options */
2059 if (tcp_options_parse (tcp0, &tc0->rcv_opts))
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002060 {
2061 clib_warning ("options parse fail");
2062 goto drop;
2063 }
Florin Coras6534b7a2017-07-18 05:38:03 -04002064
Dave Barach68b0fb02017-02-28 15:15:56 -05002065 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2066 * current thread pool. */
2067 pool_get (tm->connections[my_thread_index], new_tc0);
2068 clib_memcpy (new_tc0, tc0, sizeof (*new_tc0));
Dave Barach259cdae2017-05-15 16:27:05 -04002069 new_tc0->c_c_index = new_tc0 - tm->connections[my_thread_index];
Florin Coras6534b7a2017-07-18 05:38:03 -04002070 new_tc0->c_thread_index = my_thread_index;
Dave Barach68b0fb02017-02-28 15:15:56 -05002071 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2072 new_tc0->irs = seq0;
Florin Coras68810622017-07-24 17:40:28 -07002073 new_tc0->timers[TCP_TIMER_ESTABLISH] = TCP_TIMER_HANDLE_INVALID;
2074 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] =
2075 TCP_TIMER_HANDLE_INVALID;
2076
2077 /* If this is not the owning thread, wait for syn retransmit to
2078 * expire and cleanup then */
2079 if (tcp_half_open_connection_cleanup (tc0))
2080 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
Dave Barach68b0fb02017-02-28 15:15:56 -05002081
Florin Coras93992a92017-05-24 18:03:56 -07002082 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05002083 {
Florin Coras93992a92017-05-24 18:03:56 -07002084 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
Dave Barach68b0fb02017-02-28 15:15:56 -05002085 new_tc0->tsval_recent_age = tcp_time_now ();
2086 }
2087
Florin Coras93992a92017-05-24 18:03:56 -07002088 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2089 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
Dave Barach68b0fb02017-02-28 15:15:56 -05002090
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002091 /* RFC1323: SYN and SYN-ACK wnd not scaled */
2092 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window);
Dave Barach68b0fb02017-02-28 15:15:56 -05002093 new_tc0->snd_wl1 = seq0;
2094 new_tc0->snd_wl2 = ack0;
2095
Florin Corase04c2992017-03-01 08:17:34 -08002096 tcp_connection_init_vars (new_tc0);
2097
Dave Barach68b0fb02017-02-28 15:15:56 -05002098 /* SYN-ACK: See if we can switch to ESTABLISHED state */
Florin Coras6534b7a2017-07-18 05:38:03 -04002099 if (PREDICT_TRUE (tcp_ack (tcp0)))
Dave Barach68b0fb02017-02-28 15:15:56 -05002100 {
2101 /* Our SYN is ACKed: we have iss < ack = snd_una */
2102
2103 /* TODO Dequeue acknowledged segments if we support Fast Open */
2104 new_tc0->snd_una = ack0;
2105 new_tc0->state = TCP_STATE_ESTABLISHED;
2106
Florin Corase04c2992017-03-01 08:17:34 -08002107 /* Make sure las is initialized for the wnd computation */
2108 new_tc0->rcv_las = new_tc0->rcv_nxt;
2109
Florin Corasf03a59a2017-06-09 21:07:32 -07002110 /* Notify app that we have connection. If session layer can't
2111 * allocate session send reset */
Florin Coras68810622017-07-24 17:40:28 -07002112 if (stream_session_connect_notify (&new_tc0->connection, 0))
Florin Corasf03a59a2017-06-09 21:07:32 -07002113 {
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002114 clib_warning ("connect notify fail");
Florin Coras1f152cd2017-08-18 19:28:03 -07002115 tcp_send_reset_w_pkt (new_tc0, b0, is_ip4);
Florin Corasf03a59a2017-06-09 21:07:32 -07002116 tcp_connection_cleanup (new_tc0);
Florin Corasf03a59a2017-06-09 21:07:32 -07002117 goto drop;
2118 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002119
2120 /* Make sure after data segment processing ACK is sent */
2121 new_tc0->flags |= TCP_CONN_SNDACK;
Dave Barach2c25a622017-06-26 11:35:07 -04002122
2123 /* Update rtt with the syn-ack sample */
Dave Barach2c25a622017-06-26 11:35:07 -04002124 tcp_update_rtt (new_tc0, vnet_buffer (b0)->tcp.ack_number);
Florin Coras6534b7a2017-07-18 05:38:03 -04002125 TCP_EVT_DBG (TCP_EVT_SYNACK_RCVD, new_tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002126 }
2127 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2128 else
2129 {
2130 new_tc0->state = TCP_STATE_SYN_RCVD;
2131
Florin Corase69f4952017-03-07 10:06:24 -08002132 /* Notify app that we have connection */
Florin Coras68810622017-07-24 17:40:28 -07002133 if (stream_session_connect_notify (&new_tc0->connection, 0))
Florin Corasf03a59a2017-06-09 21:07:32 -07002134 {
2135 tcp_connection_cleanup (new_tc0);
Florin Coras1f152cd2017-08-18 19:28:03 -07002136 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
Florin Coras6534b7a2017-07-18 05:38:03 -04002137 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc0);
Florin Corasf03a59a2017-06-09 21:07:32 -07002138 goto drop;
2139 }
2140
Dave Barach2c25a622017-06-26 11:35:07 -04002141 tc0->rtt_ts = 0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002142 tcp_init_snd_vars (tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002143 tcp_make_synack (new_tc0, b0);
2144 next0 = tcp_next_output (is_ip4);
2145
2146 goto drop;
2147 }
2148
2149 /* Read data, if any */
Florin Coras6534b7a2017-07-18 05:38:03 -04002150 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
Dave Barach68b0fb02017-02-28 15:15:56 -05002151 {
Florin Coras6534b7a2017-07-18 05:38:03 -04002152 ASSERT (0);
2153 error0 = tcp_segment_rcv (tm, new_tc0, b0, &next0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002154 if (error0 == TCP_ERROR_PURE_ACK)
2155 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2156 }
2157 else
2158 {
2159 tcp_make_ack (new_tc0, b0);
2160 next0 = tcp_next_output (new_tc0->c_is_ip4);
2161 }
2162
2163 drop:
2164
2165 b0->error = error0 ? node->errors[error0] : 0;
Chris Luke879ace32017-09-26 13:15:16 -04002166 if (PREDICT_FALSE
2167 ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
Dave Barach68b0fb02017-02-28 15:15:56 -05002168 {
Clement Durand6cf260c2017-04-13 13:27:04 +02002169 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2170 clib_memcpy (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2171 clib_memcpy (&t0->tcp_connection, tc0,
2172 sizeof (t0->tcp_connection));
Dave Barach68b0fb02017-02-28 15:15:56 -05002173 }
2174
2175 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2176 n_left_to_next, bi0, next0);
2177 }
2178
2179 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2180 }
2181
2182 errors = session_manager_flush_enqueue_events (my_thread_index);
2183 if (errors)
2184 {
2185 if (is_ip4)
2186 vlib_node_increment_counter (vm, tcp4_established_node.index,
2187 TCP_ERROR_EVENT_FIFO_FULL, errors);
2188 else
2189 vlib_node_increment_counter (vm, tcp6_established_node.index,
2190 TCP_ERROR_EVENT_FIFO_FULL, errors);
2191 }
2192
2193 return from_frame->n_vectors;
2194}
2195
2196static uword
2197tcp4_syn_sent (vlib_main_t * vm, vlib_node_runtime_t * node,
2198 vlib_frame_t * from_frame)
2199{
2200 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2201}
2202
2203static uword
2204tcp6_syn_sent_rcv (vlib_main_t * vm, vlib_node_runtime_t * node,
2205 vlib_frame_t * from_frame)
2206{
2207 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2208}
2209
2210/* *INDENT-OFF* */
2211VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2212{
2213 .function = tcp4_syn_sent,
2214 .name = "tcp4-syn-sent",
2215 /* Takes a vector of packets. */
2216 .vector_size = sizeof (u32),
2217 .n_errors = TCP_N_ERROR,
2218 .error_strings = tcp_error_strings,
2219 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2220 .next_nodes =
2221 {
2222#define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2223 foreach_tcp_state_next
2224#undef _
2225 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002226 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002227};
2228/* *INDENT-ON* */
2229
2230VLIB_NODE_FUNCTION_MULTIARCH (tcp4_syn_sent_node, tcp4_syn_sent);
2231
2232/* *INDENT-OFF* */
2233VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2234{
2235 .function = tcp6_syn_sent_rcv,
2236 .name = "tcp6-syn-sent",
2237 /* Takes a vector of packets. */
2238 .vector_size = sizeof (u32),
2239 .n_errors = TCP_N_ERROR,
2240 .error_strings = tcp_error_strings,
2241 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2242 .next_nodes =
2243 {
2244#define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2245 foreach_tcp_state_next
2246#undef _
Clement Durand6cf260c2017-04-13 13:27:04 +02002247 },
2248 .format_trace = format_tcp_rx_trace_short,
2249};
Dave Barach68b0fb02017-02-28 15:15:56 -05002250/* *INDENT-ON* */
2251
2252VLIB_NODE_FUNCTION_MULTIARCH (tcp6_syn_sent_node, tcp6_syn_sent_rcv);
Florin Coras6534b7a2017-07-18 05:38:03 -04002253
Dave Barach68b0fb02017-02-28 15:15:56 -05002254/**
Florin Corasd79b41e2017-03-04 05:37:52 -08002255 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
Dave Barach68b0fb02017-02-28 15:15:56 -05002256 * as per RFC793 p. 64
2257 */
2258always_inline uword
2259tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2260 vlib_frame_t * from_frame, int is_ip4)
2261{
2262 tcp_main_t *tm = vnet_get_tcp_main ();
2263 u32 n_left_from, next_index, *from, *to_next;
Damjan Marion586afd72017-04-05 19:18:20 +02002264 u32 my_thread_index = vm->thread_index, errors = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002265
2266 from = vlib_frame_vector_args (from_frame);
2267 n_left_from = from_frame->n_vectors;
2268
2269 next_index = node->cached_next_index;
2270
2271 while (n_left_from > 0)
2272 {
2273 u32 n_left_to_next;
2274
2275 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2276
2277 while (n_left_from > 0 && n_left_to_next > 0)
2278 {
2279 u32 bi0;
2280 vlib_buffer_t *b0;
2281 tcp_header_t *tcp0 = 0;
2282 tcp_connection_t *tc0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002283 u32 next0 = TCP_RCV_PROCESS_NEXT_DROP, error0 = TCP_ERROR_ENQUEUED;
Florin Coras9d063042017-09-14 03:08:00 -04002284 u8 is_fin0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002285
2286 bi0 = from[0];
2287 to_next[0] = bi0;
2288 from += 1;
2289 to_next += 1;
2290 n_left_from -= 1;
2291 n_left_to_next -= 1;
2292
2293 b0 = vlib_get_buffer (vm, bi0);
2294 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2295 my_thread_index);
Florin Corasd79b41e2017-03-04 05:37:52 -08002296 if (PREDICT_FALSE (tc0 == 0))
2297 {
2298 error0 = TCP_ERROR_INVALID_CONNECTION;
2299 goto drop;
2300 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002301
Florin Coras82b13a82017-04-25 11:58:06 -07002302 tcp0 = tcp_buffer_hdr (b0);
Florin Coras9d063042017-09-14 03:08:00 -04002303 is_fin0 = tcp_is_fin (tcp0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002304
2305 /* SYNs, FINs and data consume sequence numbers */
2306 vnet_buffer (b0)->tcp.seq_end = vnet_buffer (b0)->tcp.seq_number
Florin Coras9d063042017-09-14 03:08:00 -04002307 + tcp_is_syn (tcp0) + is_fin0 + vnet_buffer (b0)->tcp.data_len;
Dave Barach68b0fb02017-02-28 15:15:56 -05002308
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002309 if (CLIB_DEBUG)
2310 {
2311 tcp_connection_t *tmp;
2312 tmp = tcp_lookup_connection (b0, my_thread_index, is_ip4);
2313 if (tmp->state != tc0->state)
2314 {
2315 clib_warning ("state changed");
2316 ASSERT (0);
2317 goto drop;
2318 }
2319 }
2320
Dave Barach68b0fb02017-02-28 15:15:56 -05002321 /*
2322 * Special treatment for CLOSED
2323 */
2324 switch (tc0->state)
2325 {
2326 case TCP_STATE_CLOSED:
2327 goto drop;
2328 break;
2329 }
2330
2331 /*
2332 * For all other states (except LISTEN)
2333 */
2334
2335 /* 1-4: check SEQ, RST, SYN */
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002336 if (PREDICT_FALSE (tcp_segment_validate (vm, tc0, b0, tcp0,
2337 &next0)))
Dave Barach68b0fb02017-02-28 15:15:56 -05002338 {
2339 error0 = TCP_ERROR_SEGMENT_INVALID;
2340 goto drop;
2341 }
2342
2343 /* 5: check the ACK field */
2344 switch (tc0->state)
2345 {
2346 case TCP_STATE_SYN_RCVD:
2347 /*
2348 * If the segment acknowledgment is not acceptable, form a
2349 * reset segment,
2350 * <SEQ=SEG.ACK><CTL=RST>
2351 * and send it.
2352 */
2353 if (!tcp_rcv_ack_is_acceptable (tc0, b0))
2354 {
Florin Corasa096f2d2017-09-28 23:49:42 -04002355 TCP_DBG ("connection not accepted");
Florin Coras1f152cd2017-08-18 19:28:03 -07002356 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05002357 goto drop;
2358 }
Florin Coras3af90fc2017-05-03 21:09:42 -07002359
2360 /* Update rtt and rto */
Florin Coras3af90fc2017-05-03 21:09:42 -07002361 tcp_update_rtt (tc0, vnet_buffer (b0)->tcp.ack_number);
2362
Dave Barach68b0fb02017-02-28 15:15:56 -05002363 /* Switch state to ESTABLISHED */
2364 tc0->state = TCP_STATE_ESTABLISHED;
2365
2366 /* Initialize session variables */
2367 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
Florin Corase04c2992017-03-01 08:17:34 -08002368 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
Florin Coras93992a92017-05-24 18:03:56 -07002369 << tc0->rcv_opts.wscale;
Dave Barach68b0fb02017-02-28 15:15:56 -05002370 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2371 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
Dave Barach68b0fb02017-02-28 15:15:56 -05002372 stream_session_accept_notify (&tc0->connection);
2373
Florin Corasab0289a2017-08-14 11:25:25 -07002374 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
Florin Coras6792ec02017-03-13 03:49:51 -07002375 tcp_retransmit_timer_reset (tc0);
Florin Corasab0289a2017-08-14 11:25:25 -07002376 tcp_timer_reset (tc0, TCP_TIMER_ESTABLISH);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002377 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002378 break;
2379 case TCP_STATE_ESTABLISHED:
2380 /* We can get packets in established state here because they
2381 * were enqueued before state change */
2382 if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
2383 goto drop;
2384
2385 break;
2386 case TCP_STATE_FIN_WAIT_1:
2387 /* In addition to the processing for the ESTABLISHED state, if
2388 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2389 * continue processing in that state. */
2390 if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
2391 goto drop;
Florin Corasd79b41e2017-03-04 05:37:52 -08002392
Florin Corasb2215d62017-08-01 16:56:58 -07002393 /* Still have to send the FIN */
2394 if (tc0->flags & TCP_CONN_FINPNDG)
2395 {
2396 /* TX fifo finally drained */
2397 if (!stream_session_tx_fifo_max_dequeue (&tc0->connection))
2398 tcp_send_fin (tc0);
2399 }
Florin Corasd79b41e2017-03-04 05:37:52 -08002400 /* If FIN is ACKed */
Florin Corasb2215d62017-08-01 16:56:58 -07002401 else if (tc0->snd_una == tc0->snd_una_max)
Florin Corasd79b41e2017-03-04 05:37:52 -08002402 {
2403 tc0->state = TCP_STATE_FIN_WAIT_2;
Florin Coras6534b7a2017-07-18 05:38:03 -04002404 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2405
Florin Coras9d063042017-09-14 03:08:00 -04002406 /* Stop all retransmit timers because we have nothing more
2407 * to send. Enable waitclose though because we're willing to
2408 * wait for peer's FIN but not indefinitely. */
2409 tcp_connection_timers_reset (tc0);
2410 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
Florin Corasd79b41e2017-03-04 05:37:52 -08002411 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002412 break;
2413 case TCP_STATE_FIN_WAIT_2:
2414 /* In addition to the processing for the ESTABLISHED state, if
2415 * the retransmission queue is empty, the user's CLOSE can be
2416 * acknowledged ("ok") but do not delete the TCB. */
2417 if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
2418 goto drop;
Dave Barach68b0fb02017-02-28 15:15:56 -05002419 break;
2420 case TCP_STATE_CLOSE_WAIT:
2421 /* Do the same processing as for the ESTABLISHED state. */
2422 if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
2423 goto drop;
2424 break;
2425 case TCP_STATE_CLOSING:
2426 /* In addition to the processing for the ESTABLISHED state, if
2427 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2428 * otherwise ignore the segment. */
2429 if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
2430 goto drop;
2431
Dave Barach68b0fb02017-02-28 15:15:56 -05002432 tc0->state = TCP_STATE_TIME_WAIT;
Florin Coras6534b7a2017-07-18 05:38:03 -04002433 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
Florin Corasa096f2d2017-09-28 23:49:42 -04002434 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
Dave Barach68b0fb02017-02-28 15:15:56 -05002435 goto drop;
2436
2437 break;
2438 case TCP_STATE_LAST_ACK:
Florin Coras93992a92017-05-24 18:03:56 -07002439 /* The only thing that [should] arrive in this state is an
Dave Barach68b0fb02017-02-28 15:15:56 -05002440 * acknowledgment of our FIN. If our FIN is now acknowledged,
2441 * delete the TCB, enter the CLOSED state, and return. */
2442
2443 if (!tcp_rcv_ack_is_acceptable (tc0, b0))
Florin Corasa096f2d2017-09-28 23:49:42 -04002444 {
2445 error0 = TCP_ERROR_ACK_INVALID;
2446 goto drop;
2447 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002448
Florin Coras9d063042017-09-14 03:08:00 -04002449 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
Florin Corasa096f2d2017-09-28 23:49:42 -04002450 /* Apparently our ACK for the peer's FIN was lost */
2451 if (is_fin0 && tc0->snd_una != tc0->snd_una_max)
Florin Coras93992a92017-05-24 18:03:56 -07002452 {
Florin Coras93992a92017-05-24 18:03:56 -07002453 tcp_send_fin (tc0);
2454 goto drop;
2455 }
2456
Florin Corasd79b41e2017-03-04 05:37:52 -08002457 tc0->state = TCP_STATE_CLOSED;
Florin Coras6534b7a2017-07-18 05:38:03 -04002458 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
Florin Corasa096f2d2017-09-28 23:49:42 -04002459 tcp_connection_timers_reset (tc0);
Florin Corasd79b41e2017-03-04 05:37:52 -08002460
2461 /* Don't delete the connection/session yet. Instead, wait a
2462 * reasonable amount of time until the pipes are cleared. In
2463 * particular, this makes sure that we won't have dead sessions
2464 * when processing events on the tx path */
Florin Corasa096f2d2017-09-28 23:49:42 -04002465 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
Florin Corasd79b41e2017-03-04 05:37:52 -08002466
Dave Barach68b0fb02017-02-28 15:15:56 -05002467 goto drop;
2468
2469 break;
2470 case TCP_STATE_TIME_WAIT:
2471 /* The only thing that can arrive in this state is a
2472 * retransmission of the remote FIN. Acknowledge it, and restart
2473 * the 2 MSL timeout. */
2474
Florin Coras93992a92017-05-24 18:03:56 -07002475 if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
2476 goto drop;
2477
2478 tcp_make_ack (tc0, b0);
Florin Corasa096f2d2017-09-28 23:49:42 -04002479 next0 = tcp_next_output (is_ip4);
2480 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
Florin Coras93992a92017-05-24 18:03:56 -07002481
Dave Barach68b0fb02017-02-28 15:15:56 -05002482 goto drop;
Florin Coras93992a92017-05-24 18:03:56 -07002483
Dave Barach68b0fb02017-02-28 15:15:56 -05002484 break;
2485 default:
2486 ASSERT (0);
2487 }
2488
2489 /* 6: check the URG bit TODO */
2490
2491 /* 7: process the segment text */
2492 switch (tc0->state)
2493 {
2494 case TCP_STATE_ESTABLISHED:
2495 case TCP_STATE_FIN_WAIT_1:
2496 case TCP_STATE_FIN_WAIT_2:
Florin Coras6534b7a2017-07-18 05:38:03 -04002497 if (vnet_buffer (b0)->tcp.data_len)
2498 error0 = tcp_segment_rcv (tm, tc0, b0, &next0);
Florin Coras9d063042017-09-14 03:08:00 -04002499 else if (is_fin0)
2500 tc0->rcv_nxt += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05002501 break;
2502 case TCP_STATE_CLOSE_WAIT:
2503 case TCP_STATE_CLOSING:
2504 case TCP_STATE_LAST_ACK:
2505 case TCP_STATE_TIME_WAIT:
2506 /* This should not occur, since a FIN has been received from the
2507 * remote side. Ignore the segment text. */
2508 break;
2509 }
2510
2511 /* 8: check the FIN bit */
Florin Coras9d063042017-09-14 03:08:00 -04002512 if (!is_fin0)
Dave Barach68b0fb02017-02-28 15:15:56 -05002513 goto drop;
2514
2515 switch (tc0->state)
2516 {
2517 case TCP_STATE_ESTABLISHED:
2518 case TCP_STATE_SYN_RCVD:
2519 /* Send FIN-ACK notify app and enter CLOSE-WAIT */
2520 tcp_connection_timers_reset (tc0);
Florin Corasd79b41e2017-03-04 05:37:52 -08002521 tcp_make_fin (tc0, b0);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002522 tc0->snd_nxt += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05002523 next0 = tcp_next_output (tc0->c_is_ip4);
2524 stream_session_disconnect_notify (&tc0->connection);
2525 tc0->state = TCP_STATE_CLOSE_WAIT;
Florin Coras6534b7a2017-07-18 05:38:03 -04002526 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002527 break;
2528 case TCP_STATE_CLOSE_WAIT:
2529 case TCP_STATE_CLOSING:
2530 case TCP_STATE_LAST_ACK:
2531 /* move along .. */
2532 break;
2533 case TCP_STATE_FIN_WAIT_1:
Florin Corasab0289a2017-08-14 11:25:25 -07002534 tc0->state = TCP_STATE_CLOSING;
2535 tcp_make_ack (tc0, b0);
2536 next0 = tcp_next_output (is_ip4);
Florin Coras6534b7a2017-07-18 05:38:03 -04002537 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
Florin Corasab0289a2017-08-14 11:25:25 -07002538 /* Wait for ACK but not forever */
2539 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
Dave Barach68b0fb02017-02-28 15:15:56 -05002540 break;
2541 case TCP_STATE_FIN_WAIT_2:
Florin Coras9d063042017-09-14 03:08:00 -04002542 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
Dave Barach68b0fb02017-02-28 15:15:56 -05002543 tc0->state = TCP_STATE_TIME_WAIT;
Florin Corasdb84e572017-05-09 18:54:52 -07002544 tcp_connection_timers_reset (tc0);
Florin Coras9d063042017-09-14 03:08:00 -04002545 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
Dave Barach68b0fb02017-02-28 15:15:56 -05002546 tcp_make_ack (tc0, b0);
2547 next0 = tcp_next_output (is_ip4);
Florin Coras6534b7a2017-07-18 05:38:03 -04002548 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002549 break;
2550 case TCP_STATE_TIME_WAIT:
Florin Coras9d063042017-09-14 03:08:00 -04002551 /* Remain in the TIME-WAIT state. Restart the time-wait
Dave Barach68b0fb02017-02-28 15:15:56 -05002552 * timeout.
2553 */
Florin Coras9d063042017-09-14 03:08:00 -04002554 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
Dave Barach68b0fb02017-02-28 15:15:56 -05002555 break;
2556 }
Florin Corase69f4952017-03-07 10:06:24 -08002557 TCP_EVT_DBG (TCP_EVT_FIN_RCVD, tc0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002558
Florin Coras82b13a82017-04-25 11:58:06 -07002559 drop:
Dave Barach68b0fb02017-02-28 15:15:56 -05002560 b0->error = error0 ? node->errors[error0] : 0;
2561
Dave Barach68b0fb02017-02-28 15:15:56 -05002562 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2563 {
Florin Coras82b13a82017-04-25 11:58:06 -07002564 tcp_rx_trace_t *t0 =
2565 vlib_add_trace (vm, node, b0, sizeof (*t0));
2566 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05002567 }
2568
2569 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2570 n_left_to_next, bi0, next0);
2571 }
2572
2573 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2574 }
2575
2576 errors = session_manager_flush_enqueue_events (my_thread_index);
2577 if (errors)
2578 {
2579 if (is_ip4)
2580 vlib_node_increment_counter (vm, tcp4_established_node.index,
2581 TCP_ERROR_EVENT_FIFO_FULL, errors);
2582 else
2583 vlib_node_increment_counter (vm, tcp6_established_node.index,
2584 TCP_ERROR_EVENT_FIFO_FULL, errors);
2585 }
2586
2587 return from_frame->n_vectors;
2588}
2589
2590static uword
2591tcp4_rcv_process (vlib_main_t * vm, vlib_node_runtime_t * node,
2592 vlib_frame_t * from_frame)
2593{
2594 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2595}
2596
2597static uword
2598tcp6_rcv_process (vlib_main_t * vm, vlib_node_runtime_t * node,
2599 vlib_frame_t * from_frame)
2600{
2601 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2602}
2603
2604/* *INDENT-OFF* */
2605VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2606{
2607 .function = tcp4_rcv_process,
2608 .name = "tcp4-rcv-process",
2609 /* Takes a vector of packets. */
2610 .vector_size = sizeof (u32),
2611 .n_errors = TCP_N_ERROR,
2612 .error_strings = tcp_error_strings,
2613 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2614 .next_nodes =
2615 {
2616#define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2617 foreach_tcp_state_next
2618#undef _
2619 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002620 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002621};
2622/* *INDENT-ON* */
2623
2624VLIB_NODE_FUNCTION_MULTIARCH (tcp4_rcv_process_node, tcp4_rcv_process);
2625
2626/* *INDENT-OFF* */
2627VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
2628{
2629 .function = tcp6_rcv_process,
2630 .name = "tcp6-rcv-process",
2631 /* Takes a vector of packets. */
2632 .vector_size = sizeof (u32),
2633 .n_errors = TCP_N_ERROR,
2634 .error_strings = tcp_error_strings,
2635 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2636 .next_nodes =
2637 {
2638#define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2639 foreach_tcp_state_next
2640#undef _
2641 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002642 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002643};
2644/* *INDENT-ON* */
2645
2646VLIB_NODE_FUNCTION_MULTIARCH (tcp6_rcv_process_node, tcp6_rcv_process);
2647
2648vlib_node_registration_t tcp4_listen_node;
2649vlib_node_registration_t tcp6_listen_node;
2650
2651/**
2652 * LISTEN state processing as per RFC 793 p. 65
2653 */
2654always_inline uword
2655tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2656 vlib_frame_t * from_frame, int is_ip4)
2657{
2658 u32 n_left_from, next_index, *from, *to_next;
Damjan Marion586afd72017-04-05 19:18:20 +02002659 u32 my_thread_index = vm->thread_index;
Dave Barach68b0fb02017-02-28 15:15:56 -05002660 u8 sst = is_ip4 ? SESSION_TYPE_IP4_TCP : SESSION_TYPE_IP6_TCP;
2661
2662 from = vlib_frame_vector_args (from_frame);
2663 n_left_from = from_frame->n_vectors;
2664
2665 next_index = node->cached_next_index;
2666
2667 while (n_left_from > 0)
2668 {
2669 u32 n_left_to_next;
2670
2671 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2672
2673 while (n_left_from > 0 && n_left_to_next > 0)
2674 {
2675 u32 bi0;
2676 vlib_buffer_t *b0;
Clement Durand6cf260c2017-04-13 13:27:04 +02002677 tcp_rx_trace_t *t0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002678 tcp_header_t *th0 = 0;
2679 tcp_connection_t *lc0;
2680 ip4_header_t *ip40;
2681 ip6_header_t *ip60;
2682 tcp_connection_t *child0;
2683 u32 error0 = TCP_ERROR_SYNS_RCVD, next0 = TCP_LISTEN_NEXT_DROP;
2684
2685 bi0 = from[0];
2686 to_next[0] = bi0;
2687 from += 1;
2688 to_next += 1;
2689 n_left_from -= 1;
2690 n_left_to_next -= 1;
2691
2692 b0 = vlib_get_buffer (vm, bi0);
2693 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
2694
2695 if (is_ip4)
2696 {
2697 ip40 = vlib_buffer_get_current (b0);
2698 th0 = ip4_next_header (ip40);
2699 }
2700 else
2701 {
2702 ip60 = vlib_buffer_get_current (b0);
2703 th0 = ip6_next_header (ip60);
2704 }
2705
2706 /* Create child session. For syn-flood protection use filter */
2707
Florin Corasdc629cd2017-05-09 00:52:37 -07002708 /* 1. first check for an RST: handled in dispatch */
2709 /* if (tcp_rst (th0))
2710 goto drop; */
Dave Barach68b0fb02017-02-28 15:15:56 -05002711
Florin Corasdc629cd2017-05-09 00:52:37 -07002712 /* 2. second check for an ACK: handled in dispatch */
2713 /* if (tcp_ack (th0))
2714 {
2715 tcp_send_reset (b0, is_ip4);
2716 goto drop;
2717 } */
Dave Barach68b0fb02017-02-28 15:15:56 -05002718
2719 /* 3. check for a SYN (did that already) */
2720
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002721 /* Make sure connection wasn't just created */
2722 child0 = tcp_lookup_connection (b0, my_thread_index, is_ip4);
2723 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
2724 {
2725 error0 = TCP_ERROR_CREATE_EXISTS;
2726 goto drop;
2727 }
2728
Dave Barach68b0fb02017-02-28 15:15:56 -05002729 /* Create child session and send SYN-ACK */
Florin Coras6534b7a2017-07-18 05:38:03 -04002730 child0 = tcp_connection_new (my_thread_index);
Dave Barach68b0fb02017-02-28 15:15:56 -05002731 child0->c_lcl_port = lc0->c_lcl_port;
2732 child0->c_rmt_port = th0->src_port;
2733 child0->c_is_ip4 = is_ip4;
Florin Corasbb292f42017-05-19 09:49:19 -07002734 child0->state = TCP_STATE_SYN_RCVD;
Dave Barach68b0fb02017-02-28 15:15:56 -05002735
2736 if (is_ip4)
2737 {
2738 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
2739 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
2740 }
2741 else
2742 {
2743 clib_memcpy (&child0->c_lcl_ip6, &ip60->dst_address,
2744 sizeof (ip6_address_t));
2745 clib_memcpy (&child0->c_rmt_ip6, &ip60->src_address,
2746 sizeof (ip6_address_t));
2747 }
2748
2749 if (stream_session_accept (&child0->connection, lc0->c_s_index, sst,
2750 0 /* notify */ ))
2751 {
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002752 clib_warning ("session accept fail");
2753 tcp_connection_cleanup (child0);
Dave Barach68b0fb02017-02-28 15:15:56 -05002754 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2755 goto drop;
2756 }
2757
Florin Coras93992a92017-05-24 18:03:56 -07002758 if (tcp_options_parse (th0, &child0->rcv_opts))
Florin Corasdb84e572017-05-09 18:54:52 -07002759 {
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002760 clib_warning ("options parse fail");
Florin Corasdb84e572017-05-09 18:54:52 -07002761 goto drop;
2762 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002763
2764 child0->irs = vnet_buffer (b0)->tcp.seq_number;
2765 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
Florin Coras3e350af2017-03-30 02:54:28 -07002766 child0->rcv_las = child0->rcv_nxt;
Dave Barach68b0fb02017-02-28 15:15:56 -05002767
2768 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
2769 * segments are used to initialize PAWS. */
Florin Coras93992a92017-05-24 18:03:56 -07002770 if (tcp_opts_tstamp (&child0->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05002771 {
Florin Coras93992a92017-05-24 18:03:56 -07002772 child0->tsval_recent = child0->rcv_opts.tsval;
Dave Barach68b0fb02017-02-28 15:15:56 -05002773 child0->tsval_recent_age = tcp_time_now ();
2774 }
2775
Florin Coras93992a92017-05-24 18:03:56 -07002776 if (tcp_opts_wscale (&child0->rcv_opts))
2777 child0->snd_wscale = child0->rcv_opts.wscale;
Florin Corase04c2992017-03-01 08:17:34 -08002778
Florin Corasf03a59a2017-06-09 21:07:32 -07002779 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
2780 << child0->snd_wscale;
Florin Corase04c2992017-03-01 08:17:34 -08002781 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2782 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2783
2784 tcp_connection_init_vars (child0);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002785 TCP_EVT_DBG (TCP_EVT_SYN_RCVD, child0, 1);
Florin Corase69f4952017-03-07 10:06:24 -08002786
Dave Barach68b0fb02017-02-28 15:15:56 -05002787 /* Reuse buffer to make syn-ack and send */
2788 tcp_make_synack (child0, b0);
2789 next0 = tcp_next_output (is_ip4);
Florin Corasab0289a2017-08-14 11:25:25 -07002790 tcp_timer_set (child0, TCP_TIMER_ESTABLISH, TCP_SYN_RCVD_TIME);
Dave Barach68b0fb02017-02-28 15:15:56 -05002791
2792 drop:
2793 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2794 {
Clement Durand6cf260c2017-04-13 13:27:04 +02002795 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2796 clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2797 clib_memcpy (&t0->tcp_connection, lc0,
2798 sizeof (t0->tcp_connection));
Dave Barach68b0fb02017-02-28 15:15:56 -05002799 }
2800
Florin Corase04c2992017-03-01 08:17:34 -08002801 b0->error = node->errors[error0];
Dave Barach68b0fb02017-02-28 15:15:56 -05002802
2803 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2804 n_left_to_next, bi0, next0);
2805 }
2806
2807 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2808 }
2809 return from_frame->n_vectors;
2810}
2811
2812static uword
2813tcp4_listen (vlib_main_t * vm, vlib_node_runtime_t * node,
2814 vlib_frame_t * from_frame)
2815{
2816 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2817}
2818
2819static uword
2820tcp6_listen (vlib_main_t * vm, vlib_node_runtime_t * node,
2821 vlib_frame_t * from_frame)
2822{
2823 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2824}
2825
2826/* *INDENT-OFF* */
2827VLIB_REGISTER_NODE (tcp4_listen_node) =
2828{
2829 .function = tcp4_listen,
2830 .name = "tcp4-listen",
2831 /* Takes a vector of packets. */
2832 .vector_size = sizeof (u32),
2833 .n_errors = TCP_N_ERROR,
2834 .error_strings = tcp_error_strings,
2835 .n_next_nodes = TCP_LISTEN_N_NEXT,
2836 .next_nodes =
2837 {
2838#define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2839 foreach_tcp_state_next
2840#undef _
2841 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002842 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002843};
2844/* *INDENT-ON* */
2845
2846VLIB_NODE_FUNCTION_MULTIARCH (tcp4_listen_node, tcp4_listen);
2847
2848/* *INDENT-OFF* */
2849VLIB_REGISTER_NODE (tcp6_listen_node) =
2850{
2851 .function = tcp6_listen,
2852 .name = "tcp6-listen",
2853 /* Takes a vector of packets. */
2854 .vector_size = sizeof (u32),
2855 .n_errors = TCP_N_ERROR,
2856 .error_strings = tcp_error_strings,
2857 .n_next_nodes = TCP_LISTEN_N_NEXT,
2858 .next_nodes =
2859 {
2860#define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
2861 foreach_tcp_state_next
2862#undef _
2863 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002864 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002865};
2866/* *INDENT-ON* */
2867
2868VLIB_NODE_FUNCTION_MULTIARCH (tcp6_listen_node, tcp6_listen);
2869
2870vlib_node_registration_t tcp4_input_node;
2871vlib_node_registration_t tcp6_input_node;
2872
2873typedef enum _tcp_input_next
2874{
2875 TCP_INPUT_NEXT_DROP,
2876 TCP_INPUT_NEXT_LISTEN,
2877 TCP_INPUT_NEXT_RCV_PROCESS,
2878 TCP_INPUT_NEXT_SYN_SENT,
2879 TCP_INPUT_NEXT_ESTABLISHED,
2880 TCP_INPUT_NEXT_RESET,
Pierre Pfister7fe51f32017-09-20 08:48:36 +02002881 TCP_INPUT_NEXT_PUNT,
Dave Barach68b0fb02017-02-28 15:15:56 -05002882 TCP_INPUT_N_NEXT
2883} tcp_input_next_t;
2884
2885#define foreach_tcp4_input_next \
2886 _ (DROP, "error-drop") \
2887 _ (LISTEN, "tcp4-listen") \
2888 _ (RCV_PROCESS, "tcp4-rcv-process") \
2889 _ (SYN_SENT, "tcp4-syn-sent") \
2890 _ (ESTABLISHED, "tcp4-established") \
Pierre Pfister7fe51f32017-09-20 08:48:36 +02002891 _ (RESET, "tcp4-reset") \
2892 _ (PUNT, "error-punt")
Dave Barach68b0fb02017-02-28 15:15:56 -05002893
2894#define foreach_tcp6_input_next \
2895 _ (DROP, "error-drop") \
2896 _ (LISTEN, "tcp6-listen") \
2897 _ (RCV_PROCESS, "tcp6-rcv-process") \
2898 _ (SYN_SENT, "tcp6-syn-sent") \
2899 _ (ESTABLISHED, "tcp6-established") \
Pierre Pfister7fe51f32017-09-20 08:48:36 +02002900 _ (RESET, "tcp6-reset") \
2901 _ (PUNT, "error-punt")
Dave Barach68b0fb02017-02-28 15:15:56 -05002902
Dave Barach68b0fb02017-02-28 15:15:56 -05002903#define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
2904
2905always_inline uword
2906tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2907 vlib_frame_t * from_frame, int is_ip4)
2908{
2909 u32 n_left_from, next_index, *from, *to_next;
Damjan Marion586afd72017-04-05 19:18:20 +02002910 u32 my_thread_index = vm->thread_index;
Dave Barach68b0fb02017-02-28 15:15:56 -05002911 tcp_main_t *tm = vnet_get_tcp_main ();
Dave Barach68b0fb02017-02-28 15:15:56 -05002912
2913 from = vlib_frame_vector_args (from_frame);
2914 n_left_from = from_frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002915 next_index = node->cached_next_index;
Florin Coras82d3ec82017-08-14 08:10:42 -07002916 tcp_set_time_now (my_thread_index);
Dave Barach68b0fb02017-02-28 15:15:56 -05002917
2918 while (n_left_from > 0)
2919 {
2920 u32 n_left_to_next;
2921
2922 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2923
2924 while (n_left_from > 0 && n_left_to_next > 0)
2925 {
Florin Coras82b13a82017-04-25 11:58:06 -07002926 int n_advance_bytes0, n_data_bytes0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002927 u32 bi0;
2928 vlib_buffer_t *b0;
2929 tcp_header_t *tcp0 = 0;
2930 tcp_connection_t *tc0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002931 transport_connection_t *tconn;
Dave Barach68b0fb02017-02-28 15:15:56 -05002932 ip4_header_t *ip40;
2933 ip6_header_t *ip60;
2934 u32 error0 = TCP_ERROR_NO_LISTENER, next0 = TCP_INPUT_NEXT_DROP;
2935 u8 flags0;
2936
2937 bi0 = from[0];
2938 to_next[0] = bi0;
2939 from += 1;
2940 to_next += 1;
2941 n_left_from -= 1;
2942 n_left_to_next -= 1;
2943
2944 b0 = vlib_get_buffer (vm, bi0);
Florin Corasd79b41e2017-03-04 05:37:52 -08002945 vnet_buffer (b0)->tcp.flags = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002946
Florin Coras82b13a82017-04-25 11:58:06 -07002947 /* Checksum computed by ipx_local no need to compute again */
2948
Dave Barach68b0fb02017-02-28 15:15:56 -05002949 if (is_ip4)
2950 {
2951 ip40 = vlib_buffer_get_current (b0);
2952 tcp0 = ip4_next_header (ip40);
Florin Coras82b13a82017-04-25 11:58:06 -07002953 n_advance_bytes0 = (ip4_header_bytes (ip40)
2954 + tcp_header_bytes (tcp0));
2955 n_data_bytes0 = clib_net_to_host_u16 (ip40->length)
2956 - n_advance_bytes0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002957 tconn = stream_session_lookup_transport_wt4 (&ip40->dst_address,
2958 &ip40->src_address,
2959 tcp0->dst_port,
2960 tcp0->src_port,
2961 SESSION_TYPE_IP4_TCP,
2962 my_thread_index);
2963 tc0 = tcp_get_connection_from_transport (tconn);
Florin Coras6534b7a2017-07-18 05:38:03 -04002964 ASSERT (tcp_lookup_is_valid (tc0, tcp0));
Dave Barach68b0fb02017-02-28 15:15:56 -05002965 }
2966 else
2967 {
2968 ip60 = vlib_buffer_get_current (b0);
2969 tcp0 = ip6_next_header (ip60);
Florin Coras82b13a82017-04-25 11:58:06 -07002970 n_advance_bytes0 = tcp_header_bytes (tcp0);
2971 n_data_bytes0 = clib_net_to_host_u16 (ip60->payload_length)
2972 - n_advance_bytes0;
2973 n_advance_bytes0 += sizeof (ip60[0]);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002974 tconn = stream_session_lookup_transport_wt6 (&ip60->dst_address,
2975 &ip60->src_address,
2976 tcp0->dst_port,
2977 tcp0->src_port,
2978 SESSION_TYPE_IP6_TCP,
2979 my_thread_index);
2980 tc0 = tcp_get_connection_from_transport (tconn);
Florin Coras6534b7a2017-07-18 05:38:03 -04002981 ASSERT (tcp_lookup_is_valid (tc0, tcp0));
Dave Barach68b0fb02017-02-28 15:15:56 -05002982 }
2983
Florin Coras82b13a82017-04-25 11:58:06 -07002984 /* Length check */
2985 if (PREDICT_FALSE (n_advance_bytes0 < 0))
2986 {
2987 error0 = TCP_ERROR_LENGTH;
2988 goto done;
2989 }
2990
Dave Barach68b0fb02017-02-28 15:15:56 -05002991 /* Session exists */
2992 if (PREDICT_TRUE (0 != tc0))
2993 {
2994 /* Save connection index */
2995 vnet_buffer (b0)->tcp.connection_index = tc0->c_c_index;
2996 vnet_buffer (b0)->tcp.seq_number =
2997 clib_net_to_host_u32 (tcp0->seq_number);
2998 vnet_buffer (b0)->tcp.ack_number =
2999 clib_net_to_host_u32 (tcp0->ack_number);
3000
Florin Coras82b13a82017-04-25 11:58:06 -07003001 vnet_buffer (b0)->tcp.hdr_offset = (u8 *) tcp0
3002 - (u8 *) vlib_buffer_get_current (b0);
3003 vnet_buffer (b0)->tcp.data_offset = n_advance_bytes0;
3004 vnet_buffer (b0)->tcp.data_len = n_data_bytes0;
3005
Dave Barach68b0fb02017-02-28 15:15:56 -05003006 flags0 = tcp0->flags & filter_flags;
3007 next0 = tm->dispatch_table[tc0->state][flags0].next;
3008 error0 = tm->dispatch_table[tc0->state][flags0].error;
3009
Florin Corasdc629cd2017-05-09 00:52:37 -07003010 if (PREDICT_FALSE (error0 == TCP_ERROR_DISPATCH
3011 || next0 == TCP_INPUT_NEXT_RESET))
Dave Barach68b0fb02017-02-28 15:15:56 -05003012 {
3013 /* Overload tcp flags to store state */
Florin Corasdc629cd2017-05-09 00:52:37 -07003014 tcp_state_t state0 = tc0->state;
Dave Barach68b0fb02017-02-28 15:15:56 -05003015 vnet_buffer (b0)->tcp.flags = tc0->state;
Florin Corasdc629cd2017-05-09 00:52:37 -07003016
3017 if (error0 == TCP_ERROR_DISPATCH)
3018 clib_warning ("disp error state %U flags %U",
Florin Corasbb292f42017-05-19 09:49:19 -07003019 format_tcp_state, state0, format_tcp_flags,
Florin Corasdc629cd2017-05-09 00:52:37 -07003020 (int) flags0);
Dave Barach68b0fb02017-02-28 15:15:56 -05003021 }
3022 }
3023 else
3024 {
Pierre Pfister7fe51f32017-09-20 08:48:36 +02003025 if ((is_ip4 && tm->punt_unknown4) ||
3026 (!is_ip4 && tm->punt_unknown6))
3027 {
3028 next0 = TCP_INPUT_NEXT_PUNT;
3029 error0 = TCP_ERROR_PUNT;
3030 }
3031 else
3032 {
3033 /* Send reset */
3034 next0 = TCP_INPUT_NEXT_RESET;
3035 error0 = TCP_ERROR_NO_LISTENER;
3036 }
Dave Barach68b0fb02017-02-28 15:15:56 -05003037 }
3038
Florin Coras82b13a82017-04-25 11:58:06 -07003039 done:
Dave Barach68b0fb02017-02-28 15:15:56 -05003040 b0->error = error0 ? node->errors[error0] : 0;
3041
3042 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3043 {
Florin Coras82b13a82017-04-25 11:58:06 -07003044 tcp_rx_trace_t *t0 =
3045 vlib_add_trace (vm, node, b0, sizeof (*t0));
3046 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05003047 }
Dave Barach68b0fb02017-02-28 15:15:56 -05003048 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
3049 n_left_to_next, bi0, next0);
3050 }
3051
3052 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
3053 }
3054
3055 return from_frame->n_vectors;
3056}
3057
3058static uword
3059tcp4_input (vlib_main_t * vm, vlib_node_runtime_t * node,
3060 vlib_frame_t * from_frame)
3061{
3062 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3063}
3064
3065static uword
3066tcp6_input (vlib_main_t * vm, vlib_node_runtime_t * node,
3067 vlib_frame_t * from_frame)
3068{
3069 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3070}
3071
3072/* *INDENT-OFF* */
3073VLIB_REGISTER_NODE (tcp4_input_node) =
3074{
3075 .function = tcp4_input,
3076 .name = "tcp4-input",
3077 /* Takes a vector of packets. */
3078 .vector_size = sizeof (u32),
3079 .n_errors = TCP_N_ERROR,
3080 .error_strings = tcp_error_strings,
3081 .n_next_nodes = TCP_INPUT_N_NEXT,
3082 .next_nodes =
3083 {
3084#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3085 foreach_tcp4_input_next
3086#undef _
3087 },
3088 .format_buffer = format_tcp_header,
3089 .format_trace = format_tcp_rx_trace,
3090};
3091/* *INDENT-ON* */
3092
3093VLIB_NODE_FUNCTION_MULTIARCH (tcp4_input_node, tcp4_input);
3094
3095/* *INDENT-OFF* */
3096VLIB_REGISTER_NODE (tcp6_input_node) =
3097{
3098 .function = tcp6_input,
3099 .name = "tcp6-input",
3100 /* Takes a vector of packets. */
3101 .vector_size = sizeof (u32),
3102 .n_errors = TCP_N_ERROR,
3103 .error_strings = tcp_error_strings,
3104 .n_next_nodes = TCP_INPUT_N_NEXT,
3105 .next_nodes =
3106 {
3107#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3108 foreach_tcp6_input_next
3109#undef _
3110 },
3111 .format_buffer = format_tcp_header,
3112 .format_trace = format_tcp_rx_trace,
3113};
3114/* *INDENT-ON* */
3115
3116VLIB_NODE_FUNCTION_MULTIARCH (tcp6_input_node, tcp6_input);
Dave Barach68b0fb02017-02-28 15:15:56 -05003117
3118static void
3119tcp_dispatch_table_init (tcp_main_t * tm)
3120{
3121 int i, j;
3122 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3123 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3124 {
3125 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3126 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3127 }
3128
3129#define _(t,f,n,e) \
3130do { \
3131 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3132 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3133} while (0)
3134
3135 /* SYNs for new connections -> tcp-listen. */
3136 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
Florin Corasdc629cd2017-05-09 00:52:37 -07003137 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3138 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003139 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3140 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003141 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3142 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasc28764f2017-04-26 00:08:42 -07003143 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003144 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003145 /* SYN-ACK for a SYN */
3146 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3147 TCP_ERROR_NONE);
3148 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3149 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3150 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3151 TCP_ERROR_NONE);
3152 /* ACK for for established connection -> tcp-established. */
3153 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3154 /* FIN for for established connection -> tcp-established. */
3155 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3156 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3157 TCP_ERROR_NONE);
Florin Corasd79b41e2017-03-04 05:37:52 -08003158 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Corasdc629cd2017-05-09 00:52:37 -07003159 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3160 TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003161 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Coras3eb50622017-07-13 01:24:57 -04003162 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3163 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003164 /* ACK or FIN-ACK to our FIN */
3165 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3166 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3167 TCP_ERROR_NONE);
3168 /* FIN in reply to our FIN from the other side */
3169 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003170 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003171 /* FIN confirming that the peer (app) has closed */
3172 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasf6d68ed2017-05-07 19:12:02 -07003173 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003174 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3175 TCP_ERROR_NONE);
Florin Corasf03a59a2017-06-09 21:07:32 -07003176 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3177 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3178 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003179 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras93992a92017-05-24 18:03:56 -07003180 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3181 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3182 TCP_ERROR_NONE);
Florin Corasdb84e572017-05-09 18:54:52 -07003183 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras93992a92017-05-24 18:03:56 -07003184 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3185 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3186 TCP_ERROR_NONE);
Florin Coras3eb50622017-07-13 01:24:57 -04003187 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras50958952017-08-29 14:50:13 -07003188 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras9d063042017-09-14 03:08:00 -04003189 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
Florin Corasdc629cd2017-05-09 00:52:37 -07003190 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
Florin Coras9d063042017-09-14 03:08:00 -04003191 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
Dave Barach2c25a622017-06-26 11:35:07 -04003192 TCP_ERROR_CONNECTION_CLOSED);
Dave Barach68b0fb02017-02-28 15:15:56 -05003193#undef _
3194}
3195
3196clib_error_t *
3197tcp_input_init (vlib_main_t * vm)
3198{
3199 clib_error_t *error = 0;
3200 tcp_main_t *tm = vnet_get_tcp_main ();
3201
3202 if ((error = vlib_call_init_function (vm, tcp_init)))
3203 return error;
3204
3205 /* Initialize dispatch table. */
3206 tcp_dispatch_table_init (tm);
3207
3208 return error;
3209}
3210
3211VLIB_INIT_FUNCTION (tcp_input_init);
3212
3213/*
3214 * fd.io coding-style-patch-verification: ON
3215 *
3216 * Local Variables:
3217 * eval: (c-set-style "gnu")
3218 * End:
3219 */