blob: f0ae8b1143455c02cccf7378f8812297c1a6d19b [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 \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -080030 _ (DROP4, "ip4-drop") \
31 _ (DROP6, "ip6-drop") \
Dave Barach68b0fb02017-02-28 15:15:56 -050032 _ (TCP4_OUTPUT, "tcp4-output") \
33 _ (TCP6_OUTPUT, "tcp6-output")
34
35typedef enum _tcp_established_next
36{
37#define _(s,n) TCP_ESTABLISHED_NEXT_##s,
38 foreach_tcp_state_next
39#undef _
40 TCP_ESTABLISHED_N_NEXT,
41} tcp_established_next_t;
42
43typedef enum _tcp_rcv_process_next
44{
45#define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
46 foreach_tcp_state_next
47#undef _
48 TCP_RCV_PROCESS_N_NEXT,
49} tcp_rcv_process_next_t;
50
51typedef enum _tcp_syn_sent_next
52{
53#define _(s,n) TCP_SYN_SENT_NEXT_##s,
54 foreach_tcp_state_next
55#undef _
56 TCP_SYN_SENT_N_NEXT,
57} tcp_syn_sent_next_t;
58
59typedef enum _tcp_listen_next
60{
61#define _(s,n) TCP_LISTEN_NEXT_##s,
62 foreach_tcp_state_next
63#undef _
64 TCP_LISTEN_N_NEXT,
65} tcp_listen_next_t;
66
67/* Generic, state independent indices */
68typedef enum _tcp_state_next
69{
70#define _(s,n) TCP_NEXT_##s,
71 foreach_tcp_state_next
72#undef _
73 TCP_STATE_N_NEXT,
74} tcp_state_next_t;
75
76#define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
77 : TCP_NEXT_TCP6_OUTPUT)
78
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -080079#define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
80 : TCP_NEXT_DROP6)
81
Dave Barach68b0fb02017-02-28 15:15:56 -050082vlib_node_registration_t tcp4_established_node;
83vlib_node_registration_t tcp6_established_node;
84
85/**
86 * Validate segment sequence number. As per RFC793:
87 *
88 * Segment Receive Test
89 * Length Window
90 * ------- ------- -------------------------------------------
91 * 0 0 SEG.SEQ = RCV.NXT
92 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
93 * >0 0 not acceptable
94 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
95 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
96 *
97 * This ultimately consists in checking if segment falls within the window.
98 * The one important difference compared to RFC793 is that we use rcv_las,
99 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
100 * peer's reference when computing our receive window.
101 *
Florin Coras6792ec02017-03-13 03:49:51 -0700102 * This:
103 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
104 * however, is too strict when we have retransmits. Instead we just check that
105 * the seq is not beyond the right edge and that the end of the segment is not
106 * less than the left edge.
107 *
108 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
109 * use rcv_nxt in the right edge window test instead of rcv_las.
110 *
Dave Barach68b0fb02017-02-28 15:15:56 -0500111 */
112always_inline u8
113tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
114{
Florin Coras6792ec02017-03-13 03:49:51 -0700115 return (seq_geq (end_seq, tc->rcv_las)
116 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
Dave Barach68b0fb02017-02-28 15:15:56 -0500117}
118
Florin Corasdb84e572017-05-09 18:54:52 -0700119/**
120 * Parse TCP header options.
121 *
122 * @param th TCP header
123 * @param to TCP options data structure to be populated
Florin Coras80231112018-12-05 15:59:31 -0800124 * @param is_syn set if packet is syn
Florin Corasdb84e572017-05-09 18:54:52 -0700125 * @return -1 if parsing failed
126 */
Florin Coras80231112018-12-05 15:59:31 -0800127static inline int
128tcp_options_parse (tcp_header_t * th, tcp_options_t * to, u8 is_syn)
Dave Barach68b0fb02017-02-28 15:15:56 -0500129{
130 const u8 *data;
131 u8 opt_len, opts_len, kind;
132 int j;
133 sack_block_t b;
134
135 opts_len = (tcp_doff (th) << 2) - sizeof (tcp_header_t);
136 data = (const u8 *) (th + 1);
137
138 /* Zero out all flags but those set in SYN */
Florin Corasd6fe5bd2018-10-16 19:52:10 -0700139 to->flags &= (TCP_OPTS_FLAG_SACK_PERMITTED | TCP_OPTS_FLAG_WSCALE
Florin Coras80231112018-12-05 15:59:31 -0800140 | TCP_OPTS_FLAG_TSTAMP | TCP_OPTION_MSS);
Dave Barach68b0fb02017-02-28 15:15:56 -0500141
142 for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
143 {
144 kind = data[0];
145
146 /* Get options length */
147 if (kind == TCP_OPTION_EOL)
148 break;
149 else if (kind == TCP_OPTION_NOOP)
Florin Corasdb84e572017-05-09 18:54:52 -0700150 {
151 opt_len = 1;
152 continue;
153 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500154 else
155 {
156 /* broken options */
157 if (opts_len < 2)
Florin Corasdb84e572017-05-09 18:54:52 -0700158 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500159 opt_len = data[1];
160
161 /* weird option length */
162 if (opt_len < 2 || opt_len > opts_len)
Florin Corasdb84e572017-05-09 18:54:52 -0700163 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500164 }
165
166 /* Parse options */
167 switch (kind)
168 {
169 case TCP_OPTION_MSS:
Florin Coras80231112018-12-05 15:59:31 -0800170 if (!is_syn)
171 break;
Dave Barach68b0fb02017-02-28 15:15:56 -0500172 if ((opt_len == TCP_OPTION_LEN_MSS) && tcp_syn (th))
173 {
174 to->flags |= TCP_OPTS_FLAG_MSS;
175 to->mss = clib_net_to_host_u16 (*(u16 *) (data + 2));
176 }
177 break;
178 case TCP_OPTION_WINDOW_SCALE:
Florin Coras80231112018-12-05 15:59:31 -0800179 if (!is_syn)
180 break;
Dave Barach68b0fb02017-02-28 15:15:56 -0500181 if ((opt_len == TCP_OPTION_LEN_WINDOW_SCALE) && tcp_syn (th))
182 {
183 to->flags |= TCP_OPTS_FLAG_WSCALE;
184 to->wscale = data[2];
185 if (to->wscale > TCP_MAX_WND_SCALE)
186 {
187 clib_warning ("Illegal window scaling value: %d",
188 to->wscale);
189 to->wscale = TCP_MAX_WND_SCALE;
190 }
191 }
192 break;
193 case TCP_OPTION_TIMESTAMP:
Florin Coras80231112018-12-05 15:59:31 -0800194 if (is_syn)
195 to->flags |= TCP_OPTS_FLAG_TSTAMP;
196 if ((to->flags & TCP_OPTS_FLAG_TSTAMP)
197 && opt_len == TCP_OPTION_LEN_TIMESTAMP)
Dave Barach68b0fb02017-02-28 15:15:56 -0500198 {
Dave Barach68b0fb02017-02-28 15:15:56 -0500199 to->tsval = clib_net_to_host_u32 (*(u32 *) (data + 2));
200 to->tsecr = clib_net_to_host_u32 (*(u32 *) (data + 6));
201 }
202 break;
203 case TCP_OPTION_SACK_PERMITTED:
Florin Coras80231112018-12-05 15:59:31 -0800204 if (!is_syn)
205 break;
Dave Barach68b0fb02017-02-28 15:15:56 -0500206 if (opt_len == TCP_OPTION_LEN_SACK_PERMITTED && tcp_syn (th))
207 to->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
208 break;
209 case TCP_OPTION_SACK_BLOCK:
210 /* If SACK permitted was not advertised or a SYN, break */
211 if ((to->flags & TCP_OPTS_FLAG_SACK_PERMITTED) == 0 || tcp_syn (th))
212 break;
213
214 /* If too short or not correctly formatted, break */
215 if (opt_len < 10 || ((opt_len - 2) % TCP_OPTION_LEN_SACK_BLOCK))
216 break;
217
218 to->flags |= TCP_OPTS_FLAG_SACK;
219 to->n_sack_blocks = (opt_len - 2) / TCP_OPTION_LEN_SACK_BLOCK;
220 vec_reset_length (to->sacks);
221 for (j = 0; j < to->n_sack_blocks; j++)
222 {
Florin Coras3eb50622017-07-13 01:24:57 -0400223 b.start = clib_net_to_host_u32 (*(u32 *) (data + 2 + 8 * j));
224 b.end = clib_net_to_host_u32 (*(u32 *) (data + 6 + 8 * j));
Dave Barach68b0fb02017-02-28 15:15:56 -0500225 vec_add1 (to->sacks, b);
226 }
227 break;
228 default:
229 /* Nothing to see here */
230 continue;
231 }
232 }
Florin Corasdb84e572017-05-09 18:54:52 -0700233 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500234}
235
Florin Corasc28764f2017-04-26 00:08:42 -0700236/**
237 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
238 * timestamp to echo and it's less than tsval_recent, drop segment
239 * but still send an ACK in order to retain TCP's mechanism for detecting
240 * and recovering from half-open connections
241 *
242 * Or at least that's what the theory says. It seems that this might not work
243 * very well with packet reordering and fast retransmit. XXX
244 */
Dave Barach68b0fb02017-02-28 15:15:56 -0500245always_inline int
246tcp_segment_check_paws (tcp_connection_t * tc)
247{
Florin Corasea41aac2018-12-06 17:24:59 -0800248 return tcp_opts_tstamp (&tc->rcv_opts)
Florin Coras93992a92017-05-24 18:03:56 -0700249 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
Dave Barach68b0fb02017-02-28 15:15:56 -0500250}
251
252/**
Florin Corasc28764f2017-04-26 00:08:42 -0700253 * Update tsval recent
254 */
255always_inline void
256tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
257{
258 /*
259 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
260 * of an incoming segment:
261 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
262 * then the TSval from the segment is copied to TS.Recent;
263 * otherwise, the TSval is ignored.
264 */
Florin Corasf1762d62017-09-24 19:43:08 -0400265 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
266 && seq_leq (tc->rcv_las, seq_end))
Florin Corasc28764f2017-04-26 00:08:42 -0700267 {
Dave Barach2c25a622017-06-26 11:35:07 -0400268 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
Florin Coras93992a92017-05-24 18:03:56 -0700269 tc->tsval_recent = tc->rcv_opts.tsval;
Florin Corasbe72ae62018-11-01 11:23:03 -0700270 tc->tsval_recent_age = tcp_time_now_w_thread (tc->c_thread_index);
Florin Corasc28764f2017-04-26 00:08:42 -0700271 }
272}
273
274/**
Dave Barach68b0fb02017-02-28 15:15:56 -0500275 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
276 *
277 * It first verifies if segment has a wrapped sequence number (PAWS) and then
278 * does the processing associated to the first four steps (ignoring security
279 * and precedence): sequence number, rst bit and syn bit checks.
280 *
281 * @return 0 if segments passes validation.
282 */
283static int
Florin Coras7ac053b2018-11-05 15:57:21 -0800284tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
285 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
Dave Barach68b0fb02017-02-28 15:15:56 -0500286{
Florin Corasca1c8f32018-05-23 21:01:30 -0700287 /* We could get a burst of RSTs interleaved with acks */
288 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
289 {
290 tcp_send_reset (tc0);
291 *error0 = TCP_ERROR_CONNECTION_CLOSED;
Florin Coras7ac053b2018-11-05 15:57:21 -0800292 goto error;
Florin Corasca1c8f32018-05-23 21:01:30 -0700293 }
294
Dave Barach68b0fb02017-02-28 15:15:56 -0500295 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
Florin Coras00cd22d2018-04-18 13:20:18 -0700296 {
297 *error0 = TCP_ERROR_SEGMENT_INVALID;
Florin Coras7ac053b2018-11-05 15:57:21 -0800298 goto error;
Florin Coras00cd22d2018-04-18 13:20:18 -0700299 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500300
Florin Coras80231112018-12-05 15:59:31 -0800301 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
Florin Corasdb84e572017-05-09 18:54:52 -0700302 {
Florin Coras00cd22d2018-04-18 13:20:18 -0700303 *error0 = TCP_ERROR_OPTIONS;
Florin Coras7ac053b2018-11-05 15:57:21 -0800304 goto error;
Florin Corasdb84e572017-05-09 18:54:52 -0700305 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500306
Florin Coras00cd22d2018-04-18 13:20:18 -0700307 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500308 {
Florin Coras00cd22d2018-04-18 13:20:18 -0700309 *error0 = TCP_ERROR_PAWS;
Florin Corasc28764f2017-04-26 00:08:42 -0700310 TCP_EVT_DBG (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
311 vnet_buffer (b0)->tcp.seq_end);
Dave Barach68b0fb02017-02-28 15:15:56 -0500312
313 /* If it just so happens that a segment updates tsval_recent for a
314 * segment over 24 days old, invalidate tsval_recent. */
315 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
Florin Corasbe72ae62018-11-01 11:23:03 -0700316 tcp_time_now_w_thread (tc0->c_thread_index)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500317 {
Florin Corasea41aac2018-12-06 17:24:59 -0800318 tc0->tsval_recent = tc0->rcv_opts.tsval;
Florin Coras91236ce2018-12-16 11:41:45 -0800319 clib_warning ("paws failed: 24-day old segment");
Dave Barach68b0fb02017-02-28 15:15:56 -0500320 }
Florin Coras91236ce2018-12-16 11:41:45 -0800321 /* Drop after ack if not rst. Resets can fail paws check as per
322 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
323 * be subjected to the PAWS check by verifying an acceptable value in
324 * SEG.TSval */
325 else if (!tcp_rst (th0))
Dave Barach68b0fb02017-02-28 15:15:56 -0500326 {
Florin Coras91236ce2018-12-16 11:41:45 -0800327 tcp_program_ack (wrk, tc0);
328 TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
329 goto error;
Dave Barach68b0fb02017-02-28 15:15:56 -0500330 }
331 }
332
333 /* 1st: check sequence number */
334 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
335 vnet_buffer (b0)->tcp.seq_end))
336 {
Florin Coras00cd22d2018-04-18 13:20:18 -0700337 *error0 = TCP_ERROR_RCV_WND;
Florin Coras6792ec02017-03-13 03:49:51 -0700338 /* If our window is 0 and the packet is in sequence, let it pass
Florin Coras00cd22d2018-04-18 13:20:18 -0700339 * through for ack processing. It should be dropped later. */
340 if (!(tc0->rcv_wnd == 0
341 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number))
Florin Coras6792ec02017-03-13 03:49:51 -0700342 {
343 /* If not RST, send dup ack */
344 if (!tcp_rst (th0))
345 {
Florin Coras7ac053b2018-11-05 15:57:21 -0800346 tcp_program_dupack (wrk, tc0);
Florin Corasca1c8f32018-05-23 21:01:30 -0700347 TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
Florin Coras6792ec02017-03-13 03:49:51 -0700348 }
Florin Coras7ac053b2018-11-05 15:57:21 -0800349 goto error;
Florin Coras6792ec02017-03-13 03:49:51 -0700350 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500351 }
352
353 /* 2nd: check the RST bit */
Florin Coras00cd22d2018-04-18 13:20:18 -0700354 if (PREDICT_FALSE (tcp_rst (th0)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500355 {
Florin Corasd79b41e2017-03-04 05:37:52 -0800356 tcp_connection_reset (tc0);
Florin Coras00cd22d2018-04-18 13:20:18 -0700357 *error0 = TCP_ERROR_RST_RCVD;
Florin Coras7ac053b2018-11-05 15:57:21 -0800358 goto error;
Dave Barach68b0fb02017-02-28 15:15:56 -0500359 }
360
361 /* 3rd: check security and precedence (skip) */
362
363 /* 4th: check the SYN bit */
Florin Coras00cd22d2018-04-18 13:20:18 -0700364 if (PREDICT_FALSE (tcp_syn (th0)))
Dave Barach68b0fb02017-02-28 15:15:56 -0500365 {
Florin Coras6534b7a2017-07-18 05:38:03 -0400366 /* TODO implement RFC 5961 */
Florin Coras9d063042017-09-14 03:08:00 -0400367 if (tc0->state == TCP_STATE_SYN_RCVD)
368 {
Florin Coras80231112018-12-05 15:59:31 -0800369 tcp_options_parse (th0, &tc0->rcv_opts, 1);
Florin Coras7ac053b2018-11-05 15:57:21 -0800370 tcp_send_synack (tc0);
Florin Coras9d063042017-09-14 03:08:00 -0400371 TCP_EVT_DBG (TCP_EVT_SYN_RCVD, tc0, 0);
372 }
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400373 else
Florin Coras9d063042017-09-14 03:08:00 -0400374 {
Florin Coras7ac053b2018-11-05 15:57:21 -0800375 tcp_program_ack (wrk, tc0);
Florin Coras9d063042017-09-14 03:08:00 -0400376 TCP_EVT_DBG (TCP_EVT_SYNACK_RCVD, tc0);
377 }
Florin Coras00cd22d2018-04-18 13:20:18 -0700378 goto error;
Dave Barach68b0fb02017-02-28 15:15:56 -0500379 }
380
Florin Corasc28764f2017-04-26 00:08:42 -0700381 /* If segment in window, save timestamp */
382 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
383 vnet_buffer (b0)->tcp.seq_end);
Dave Barach68b0fb02017-02-28 15:15:56 -0500384 return 0;
Florin Coras00cd22d2018-04-18 13:20:18 -0700385
Florin Coras00cd22d2018-04-18 13:20:18 -0700386error:
Florin Coras00cd22d2018-04-18 13:20:18 -0700387 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500388}
389
390always_inline int
391tcp_rcv_ack_is_acceptable (tcp_connection_t * tc0, vlib_buffer_t * tb0)
392{
393 /* SND.UNA =< SEG.ACK =< SND.NXT */
394 return (seq_leq (tc0->snd_una, vnet_buffer (tb0)->tcp.ack_number)
395 && seq_leq (vnet_buffer (tb0)->tcp.ack_number, tc0->snd_nxt));
396}
397
398/**
399 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
400 *
401 * Note that although the original article, srtt and rttvar are scaled
402 * to minimize round-off errors, here we don't. Instead, we rely on
403 * better precision time measurements.
404 *
405 * TODO support us rtt resolution
406 */
407static void
408tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
409{
Florin Corasf03a59a2017-06-09 21:07:32 -0700410 int err, diff;
Dave Barach68b0fb02017-02-28 15:15:56 -0500411
412 if (tc->srtt != 0)
413 {
414 err = mrtt - tc->srtt;
Dave Barach68b0fb02017-02-28 15:15:56 -0500415
416 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
417 * The increase should be bound */
Florin Corasf03a59a2017-06-09 21:07:32 -0700418 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
419 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
420 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500421 }
422 else
423 {
424 /* First measurement. */
425 tc->srtt = mrtt;
Florin Coras6792ec02017-03-13 03:49:51 -0700426 tc->rttvar = mrtt >> 1;
Dave Barach68b0fb02017-02-28 15:15:56 -0500427 }
428}
429
Florin Coras93992a92017-05-24 18:03:56 -0700430void
431tcp_update_rto (tcp_connection_t * tc)
432{
433 tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
Florin Corasf03a59a2017-06-09 21:07:32 -0700434 tc->rto = clib_max (tc->rto, TCP_RTO_MIN);
Florin Coras93992a92017-05-24 18:03:56 -0700435}
436
Florin Corasf1762d62017-09-24 19:43:08 -0400437/**
438 * Update RTT estimate and RTO timer
Dave Barach68b0fb02017-02-28 15:15:56 -0500439 *
440 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
441 * timing. Middle boxes are known to fiddle with TCP options so we
442 * should give higher priority to ACK timing.
443 *
Florin Corasf1762d62017-09-24 19:43:08 -0400444 * This should be called only if previously sent bytes have been acked.
445 *
Dave Barach68b0fb02017-02-28 15:15:56 -0500446 * return 1 if valid rtt 0 otherwise
447 */
448static int
449tcp_update_rtt (tcp_connection_t * tc, u32 ack)
450{
451 u32 mrtt = 0;
452
453 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
454 * RTT because they're ambiguous. */
Florin Corasf1762d62017-09-24 19:43:08 -0400455 if (tcp_in_cong_recovery (tc) || tc->sack_sb.sacked_bytes)
Florin Coras3ec66b02018-08-23 16:27:05 -0700456 {
457 if (tcp_in_recovery (tc))
458 return 0;
459 goto done;
460 }
Florin Corasf1762d62017-09-24 19:43:08 -0400461
462 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
Dave Barach68b0fb02017-02-28 15:15:56 -0500463 {
Florin Corasefefc6b2018-11-07 12:49:19 -0800464 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
465 tc->mrtt_us = tc->mrtt_us + (sample - tc->mrtt_us) * 0.125;
466 mrtt = clib_max ((u32) (sample * THZ), 1);
467 /* Allow measuring of a new RTT */
468 tc->rtt_ts = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500469 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500470 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
471 * snd_una, i.e., the left side of the send window:
Florin Corasf1762d62017-09-24 19:43:08 -0400472 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
473 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
Dave Barach68b0fb02017-02-28 15:15:56 -0500474 {
Florin Corasbe72ae62018-11-01 11:23:03 -0700475 u32 now = tcp_time_now_w_thread (tc->c_thread_index);
476 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500477 }
478
Florin Corasf1762d62017-09-24 19:43:08 -0400479 /* Ignore dubious measurements */
480 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
481 goto done;
482
483 tcp_estimate_rtt (tc, mrtt);
484
485done:
486
Florin Corasf1762d62017-09-24 19:43:08 -0400487 /* If we got here something must've been ACKed so make sure boff is 0,
Florin Coras3ec66b02018-08-23 16:27:05 -0700488 * even if mrtt is not valid since we update the rto lower */
Florin Corasf1762d62017-09-24 19:43:08 -0400489 tc->rto_boff = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700490 tcp_update_rto (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500491
Florin Coras3af90fc2017-05-03 21:09:42 -0700492 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500493}
494
Florin Corasefefc6b2018-11-07 12:49:19 -0800495static void
496tcp_estimate_initial_rtt (tcp_connection_t * tc)
497{
498 u8 thread_index = vlib_num_workers ()? 1 : 0;
499 int mrtt;
500
501 if (tc->rtt_ts)
502 {
503 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
504 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
505 tc->rtt_ts = 0;
506 }
507 else
508 {
509 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
Florin Coras4af830c2018-12-04 09:21:36 -0800510 mrtt = clib_max (mrtt, 1);
Florin Corasefefc6b2018-11-07 12:49:19 -0800511 tc->mrtt_us = (f64) mrtt *TCP_TICK;
Florin Corasefefc6b2018-11-07 12:49:19 -0800512 }
513
514 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
515 tcp_estimate_rtt (tc, mrtt);
516}
517
Dave Barach68b0fb02017-02-28 15:15:56 -0500518/**
Florin Coras9ece3c02018-11-05 11:06:53 -0800519 * Dequeue bytes for connections that have received acks in last burst
Dave Barach68b0fb02017-02-28 15:15:56 -0500520 */
521static void
Florin Coras9ece3c02018-11-05 11:06:53 -0800522tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
Dave Barach68b0fb02017-02-28 15:15:56 -0500523{
Florin Coras9ece3c02018-11-05 11:06:53 -0800524 u32 thread_index = wrk->vm->thread_index;
525 u32 *pending_deq_acked;
526 tcp_connection_t *tc;
527 int i;
Florin Coras93992a92017-05-24 18:03:56 -0700528
Florin Coras9ece3c02018-11-05 11:06:53 -0800529 if (!vec_len (wrk->pending_deq_acked))
530 return;
Dave Barach68b0fb02017-02-28 15:15:56 -0500531
Florin Coras9ece3c02018-11-05 11:06:53 -0800532 pending_deq_acked = wrk->pending_deq_acked;
533 for (i = 0; i < vec_len (pending_deq_acked); i++)
534 {
535 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
536 tc->flags &= ~TCP_CONN_DEQ_PENDING;
Florin Coras93992a92017-05-24 18:03:56 -0700537
Florin Corasefefc6b2018-11-07 12:49:19 -0800538 if (PREDICT_FALSE (!tc->burst_acked))
539 continue;
540
Florin Coras9ece3c02018-11-05 11:06:53 -0800541 /* Dequeue the newly ACKed bytes */
542 stream_session_dequeue_drop (&tc->connection, tc->burst_acked);
543 tc->burst_acked = 0;
544 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
545
Florin Coras42ceddb2018-12-12 10:56:01 -0800546 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
547 {
548 if (seq_leq (tc->psh_seq, tc->snd_una))
549 tc->flags &= ~TCP_CONN_PSH_PENDING;
550 }
551
Florin Coras9ece3c02018-11-05 11:06:53 -0800552 /* If everything has been acked, stop retransmit timer
553 * otherwise update. */
554 tcp_retransmit_timer_update (tc);
Florin Corasefefc6b2018-11-07 12:49:19 -0800555
556 /* If not congested, update pacer based on our new
557 * cwnd estimate */
558 if (!tcp_in_fastrecovery (tc))
559 tcp_connection_tx_pacer_update (tc);
Florin Coras9ece3c02018-11-05 11:06:53 -0800560 }
561 _vec_len (wrk->pending_deq_acked) = 0;
562}
563
564static void
565tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
566{
567 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
568 {
569 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
570 tc->flags |= TCP_CONN_DEQ_PENDING;
571 }
572 tc->burst_acked += tc->bytes_acked + tc->sack_sb.snd_una_adv;
Dave Barach68b0fb02017-02-28 15:15:56 -0500573}
574
Florin Coras6792ec02017-03-13 03:49:51 -0700575/**
Florin Coras93992a92017-05-24 18:03:56 -0700576 * Check if duplicate ack as per RFC5681 Sec. 2
577 */
578static u8
579tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
580 u32 prev_snd_una)
Dave Barach68b0fb02017-02-28 15:15:56 -0500581{
Florin Coras93992a92017-05-24 18:03:56 -0700582 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
Dave Barach68b0fb02017-02-28 15:15:56 -0500583 && seq_gt (tc->snd_una_max, tc->snd_una)
584 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
Florin Coras93992a92017-05-24 18:03:56 -0700585 && (prev_snd_wnd == tc->snd_wnd));
586}
587
588/**
589 * Checks if ack is a congestion control event.
590 */
591static u8
592tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
593 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
594{
595 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
596 * defined to be 'duplicate' */
597 *is_dack = tc->sack_sb.last_sacked_bytes
598 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
599
Dave Barach2c25a622017-06-26 11:35:07 -0400600 return ((*is_dack || tcp_in_cong_recovery (tc)) && !tcp_is_lost_fin (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500601}
602
Florin Coras0dbd5172018-06-25 16:19:34 -0700603static u32
604scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
605{
606 ASSERT (!pool_is_free_index (sb->holes, hole - sb->holes));
607 return hole - sb->holes;
608}
609
610static u32
611scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
612{
613 return hole->end - hole->start;
614}
615
616sack_scoreboard_hole_t *
617scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
618{
619 if (index != TCP_INVALID_SACK_HOLE_INDEX)
620 return pool_elt_at_index (sb->holes, index);
621 return 0;
622}
623
624sack_scoreboard_hole_t *
625scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
626{
627 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
628 return pool_elt_at_index (sb->holes, hole->next);
629 return 0;
630}
631
632sack_scoreboard_hole_t *
633scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
634{
635 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
636 return pool_elt_at_index (sb->holes, hole->prev);
637 return 0;
638}
639
640sack_scoreboard_hole_t *
641scoreboard_first_hole (sack_scoreboard_t * sb)
642{
643 if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
644 return pool_elt_at_index (sb->holes, sb->head);
645 return 0;
646}
647
648sack_scoreboard_hole_t *
649scoreboard_last_hole (sack_scoreboard_t * sb)
650{
651 if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
652 return pool_elt_at_index (sb->holes, sb->tail);
653 return 0;
654}
655
656static void
Dave Barach68b0fb02017-02-28 15:15:56 -0500657scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
658{
659 sack_scoreboard_hole_t *next, *prev;
660
661 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
662 {
663 next = pool_elt_at_index (sb->holes, hole->next);
664 next->prev = hole->prev;
665 }
Florin Coras93992a92017-05-24 18:03:56 -0700666 else
667 {
668 sb->tail = hole->prev;
669 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500670
671 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
672 {
673 prev = pool_elt_at_index (sb->holes, hole->prev);
674 prev->next = hole->next;
675 }
676 else
677 {
678 sb->head = hole->next;
679 }
680
Florin Coras93992a92017-05-24 18:03:56 -0700681 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
682 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
683
Florin Coras3eb50622017-07-13 01:24:57 -0400684 /* Poison the entry */
685 if (CLIB_DEBUG > 0)
Dave Barachb7b92992018-10-17 10:38:51 -0400686 clib_memset (hole, 0xfe, sizeof (*hole));
Florin Coras3eb50622017-07-13 01:24:57 -0400687
Dave Barach68b0fb02017-02-28 15:15:56 -0500688 pool_put (sb->holes, hole);
689}
690
Florin Coras0dbd5172018-06-25 16:19:34 -0700691static sack_scoreboard_hole_t *
Florin Coras6792ec02017-03-13 03:49:51 -0700692scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
Dave Barach68b0fb02017-02-28 15:15:56 -0500693 u32 start, u32 end)
694{
Florin Coras6792ec02017-03-13 03:49:51 -0700695 sack_scoreboard_hole_t *hole, *next, *prev;
Dave Barach68b0fb02017-02-28 15:15:56 -0500696 u32 hole_index;
697
698 pool_get (sb->holes, hole);
Dave Barachb7b92992018-10-17 10:38:51 -0400699 clib_memset (hole, 0, sizeof (*hole));
Dave Barach68b0fb02017-02-28 15:15:56 -0500700
701 hole->start = start;
702 hole->end = end;
Florin Coras3eb50622017-07-13 01:24:57 -0400703 hole_index = scoreboard_hole_index (sb, hole);
Dave Barach68b0fb02017-02-28 15:15:56 -0500704
Florin Coras6792ec02017-03-13 03:49:51 -0700705 prev = scoreboard_get_hole (sb, prev_index);
Dave Barach68b0fb02017-02-28 15:15:56 -0500706 if (prev)
707 {
Florin Corasf03a59a2017-06-09 21:07:32 -0700708 hole->prev = prev_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500709 hole->next = prev->next;
710
711 if ((next = scoreboard_next_hole (sb, hole)))
712 next->prev = hole_index;
Florin Corasf03a59a2017-06-09 21:07:32 -0700713 else
714 sb->tail = hole_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500715
716 prev->next = hole_index;
717 }
718 else
719 {
720 sb->head = hole_index;
721 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
722 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
723 }
724
725 return hole;
726}
727
Florin Coras0dbd5172018-06-25 16:19:34 -0700728static void
Florin Corasf03a59a2017-06-09 21:07:32 -0700729scoreboard_update_bytes (tcp_connection_t * tc, sack_scoreboard_t * sb)
Florin Coras93992a92017-05-24 18:03:56 -0700730{
Florin Corasecbd20b2018-10-17 23:34:54 -0700731 sack_scoreboard_hole_t *left, *right;
Florin Coras93992a92017-05-24 18:03:56 -0700732 u32 bytes = 0, blks = 0;
733
734 sb->lost_bytes = 0;
Florin Corasf03a59a2017-06-09 21:07:32 -0700735 sb->sacked_bytes = 0;
Florin Corasecbd20b2018-10-17 23:34:54 -0700736 left = scoreboard_last_hole (sb);
737 if (!left)
Florin Coras93992a92017-05-24 18:03:56 -0700738 return;
739
Florin Corasecbd20b2018-10-17 23:34:54 -0700740 if (seq_gt (sb->high_sacked, left->end))
Florin Coras93992a92017-05-24 18:03:56 -0700741 {
Florin Corasecbd20b2018-10-17 23:34:54 -0700742 bytes = sb->high_sacked - left->end;
Florin Coras93992a92017-05-24 18:03:56 -0700743 blks = 1;
744 }
745
Florin Coras9f9e9692018-10-19 17:49:00 -0700746 while ((right = left)
747 && bytes < (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
748 && blks < TCP_DUPACK_THRESHOLD
749 /* left not updated if above conditions fail */
750 && (left = scoreboard_prev_hole (sb, right)))
Florin Coras93992a92017-05-24 18:03:56 -0700751 {
Florin Corasecbd20b2018-10-17 23:34:54 -0700752 bytes += right->start - left->end;
Florin Coras93992a92017-05-24 18:03:56 -0700753 blks++;
Florin Coras93992a92017-05-24 18:03:56 -0700754 }
755
Florin Coras9f9e9692018-10-19 17:49:00 -0700756 /* left is first lost */
757 if (left)
Florin Coras93992a92017-05-24 18:03:56 -0700758 {
Florin Coras9f9e9692018-10-19 17:49:00 -0700759 do
760 {
761 sb->lost_bytes += scoreboard_hole_bytes (right);
762 left->is_lost = 1;
763 left = scoreboard_prev_hole (sb, right);
764 if (left)
765 bytes += right->start - left->end;
766 }
767 while ((right = left));
Florin Coras93992a92017-05-24 18:03:56 -0700768 }
Florin Coras9f9e9692018-10-19 17:49:00 -0700769
Florin Corasf03a59a2017-06-09 21:07:32 -0700770 sb->sacked_bytes = bytes;
Florin Coras93992a92017-05-24 18:03:56 -0700771}
772
773/**
774 * Figure out the next hole to retransmit
775 *
776 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
777 */
778sack_scoreboard_hole_t *
779scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
780 sack_scoreboard_hole_t * start,
Florin Coras36ee9f12018-11-02 12:52:10 -0700781 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
Florin Coras93992a92017-05-24 18:03:56 -0700782{
783 sack_scoreboard_hole_t *hole = 0;
784
785 hole = start ? start : scoreboard_first_hole (sb);
786 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
787 hole = scoreboard_next_hole (sb, hole);
788
789 /* Nothing, return */
790 if (!hole)
791 {
792 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
793 return 0;
794 }
795
796 /* Rule (1): if higher than rxt, less than high_sacked and lost */
797 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
798 {
799 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
800 }
801 else
802 {
Florin Coras36ee9f12018-11-02 12:52:10 -0700803 /* Rule (2): available unsent data */
804 if (have_unsent)
Florin Coras93992a92017-05-24 18:03:56 -0700805 {
Florin Coras93992a92017-05-24 18:03:56 -0700806 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
Florin Coras36ee9f12018-11-02 12:52:10 -0700807 return 0;
Florin Coras93992a92017-05-24 18:03:56 -0700808 }
809 /* Rule (3): if hole not lost */
810 else if (seq_lt (hole->start, sb->high_sacked))
811 {
Florin Corasbf4d5ce2018-10-19 16:26:24 -0700812 *snd_limited = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700813 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
814 }
815 /* Rule (4): if hole beyond high_sacked */
816 else
817 {
818 ASSERT (seq_geq (hole->start, sb->high_sacked));
819 *snd_limited = 1;
820 *can_rescue = 1;
821 /* HighRxt MUST NOT be updated */
822 return 0;
823 }
824 }
825
826 if (hole && seq_lt (sb->high_rxt, hole->start))
827 sb->high_rxt = hole->start;
828
829 return hole;
830}
831
Florin Coras0dbd5172018-06-25 16:19:34 -0700832static void
Florin Coras36ee9f12018-11-02 12:52:10 -0700833scoreboard_init_high_rxt (sack_scoreboard_t * sb, u32 snd_una)
Florin Coras93992a92017-05-24 18:03:56 -0700834{
835 sack_scoreboard_hole_t *hole;
836 hole = scoreboard_first_hole (sb);
Florin Coras3eb50622017-07-13 01:24:57 -0400837 if (hole)
838 {
Florin Coras36ee9f12018-11-02 12:52:10 -0700839 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
Florin Coras3eb50622017-07-13 01:24:57 -0400840 sb->cur_rxt_hole = sb->head;
841 }
Florin Coras36ee9f12018-11-02 12:52:10 -0700842 sb->high_rxt = snd_una;
843 sb->rescue_rxt = snd_una - 1;
Florin Coras3eb50622017-07-13 01:24:57 -0400844}
845
Florin Coras0dbd5172018-06-25 16:19:34 -0700846void
847scoreboard_init (sack_scoreboard_t * sb)
848{
849 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
850 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
851 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
852}
853
854void
855scoreboard_clear (sack_scoreboard_t * sb)
856{
857 sack_scoreboard_hole_t *hole;
858 while ((hole = scoreboard_first_hole (sb)))
859 {
860 scoreboard_remove_hole (sb, hole);
861 }
862 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
863 ASSERT (pool_elts (sb->holes) == 0);
864 sb->sacked_bytes = 0;
865 sb->last_sacked_bytes = 0;
866 sb->last_bytes_delivered = 0;
867 sb->snd_una_adv = 0;
868 sb->high_sacked = 0;
869 sb->high_rxt = 0;
870 sb->lost_bytes = 0;
871 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
872}
873
Florin Coras3eb50622017-07-13 01:24:57 -0400874/**
875 * Test that scoreboard is sane after recovery
876 *
877 * Returns 1 if scoreboard is empty or if first hole beyond
878 * snd_una.
879 */
Florin Coras0dbd5172018-06-25 16:19:34 -0700880static u8
Florin Coras3eb50622017-07-13 01:24:57 -0400881tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
882{
883 sack_scoreboard_hole_t *hole;
884 hole = scoreboard_first_hole (&tc->sack_sb);
Florin Corasecbd20b2018-10-17 23:34:54 -0700885 return (!hole || (seq_geq (hole->start, tc->snd_una)
886 && seq_lt (hole->end, tc->snd_una_max)));
Florin Coras93992a92017-05-24 18:03:56 -0700887}
888
889void
Dave Barach68b0fb02017-02-28 15:15:56 -0500890tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
891{
892 sack_scoreboard_t *sb = &tc->sack_sb;
893 sack_block_t *blk, tmp;
Florin Corasf03a59a2017-06-09 21:07:32 -0700894 sack_scoreboard_hole_t *hole, *next_hole, *last_hole;
Florin Coras93992a92017-05-24 18:03:56 -0700895 u32 blk_index = 0, old_sacked_bytes, hole_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500896 int i, j;
897
Florin Coras6792ec02017-03-13 03:49:51 -0700898 sb->last_sacked_bytes = 0;
Florin Coras93992a92017-05-24 18:03:56 -0700899 sb->last_bytes_delivered = 0;
Florin Coras352c2c42018-06-26 01:22:41 -0700900 sb->snd_una_adv = 0;
Florin Coras6792ec02017-03-13 03:49:51 -0700901
Florin Coras93992a92017-05-24 18:03:56 -0700902 if (!tcp_opts_sack (&tc->rcv_opts)
903 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
Dave Barach68b0fb02017-02-28 15:15:56 -0500904 return;
905
Florin Coras352c2c42018-06-26 01:22:41 -0700906 old_sacked_bytes = sb->sacked_bytes;
907
Dave Barach68b0fb02017-02-28 15:15:56 -0500908 /* Remove invalid blocks */
Florin Coras93992a92017-05-24 18:03:56 -0700909 blk = tc->rcv_opts.sacks;
910 while (blk < vec_end (tc->rcv_opts.sacks))
Florin Coras6792ec02017-03-13 03:49:51 -0700911 {
912 if (seq_lt (blk->start, blk->end)
913 && seq_gt (blk->start, tc->snd_una)
Florin Corasab86f862018-12-06 18:24:19 -0800914 && seq_gt (blk->start, ack)
915 && seq_lt (blk->start, tc->snd_una_max)
916 && seq_leq (blk->end, tc->snd_una_max))
Florin Coras6792ec02017-03-13 03:49:51 -0700917 {
918 blk++;
919 continue;
920 }
Florin Coras93992a92017-05-24 18:03:56 -0700921 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
Florin Coras6792ec02017-03-13 03:49:51 -0700922 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500923
924 /* Add block for cumulative ack */
925 if (seq_gt (ack, tc->snd_una))
926 {
927 tmp.start = tc->snd_una;
928 tmp.end = ack;
Florin Coras93992a92017-05-24 18:03:56 -0700929 vec_add1 (tc->rcv_opts.sacks, tmp);
Dave Barach68b0fb02017-02-28 15:15:56 -0500930 }
931
Florin Coras93992a92017-05-24 18:03:56 -0700932 if (vec_len (tc->rcv_opts.sacks) == 0)
Dave Barach68b0fb02017-02-28 15:15:56 -0500933 return;
934
Florin Coras3eb50622017-07-13 01:24:57 -0400935 tcp_scoreboard_trace_add (tc, ack);
936
Dave Barach68b0fb02017-02-28 15:15:56 -0500937 /* Make sure blocks are ordered */
Florin Coras93992a92017-05-24 18:03:56 -0700938 for (i = 0; i < vec_len (tc->rcv_opts.sacks); i++)
939 for (j = i + 1; j < vec_len (tc->rcv_opts.sacks); j++)
940 if (seq_lt (tc->rcv_opts.sacks[j].start, tc->rcv_opts.sacks[i].start))
Dave Barach68b0fb02017-02-28 15:15:56 -0500941 {
Florin Coras93992a92017-05-24 18:03:56 -0700942 tmp = tc->rcv_opts.sacks[i];
943 tc->rcv_opts.sacks[i] = tc->rcv_opts.sacks[j];
944 tc->rcv_opts.sacks[j] = tmp;
Dave Barach68b0fb02017-02-28 15:15:56 -0500945 }
946
Dave Barach68b0fb02017-02-28 15:15:56 -0500947 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
948 {
Florin Coras6792ec02017-03-13 03:49:51 -0700949 /* If no holes, insert the first that covers all outstanding bytes */
950 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
951 tc->snd_una, tc->snd_una_max);
952 sb->tail = scoreboard_hole_index (sb, last_hole);
Florin Coras93992a92017-05-24 18:03:56 -0700953 tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
954 sb->high_sacked = tmp.end;
Florin Coras6792ec02017-03-13 03:49:51 -0700955 }
956 else
957 {
958 /* If we have holes but snd_una_max is beyond the last hole, update
959 * last hole end */
Florin Coras93992a92017-05-24 18:03:56 -0700960 tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
Florin Coras6792ec02017-03-13 03:49:51 -0700961 last_hole = scoreboard_last_hole (sb);
Dave Barach2c25a622017-06-26 11:35:07 -0400962 if (seq_gt (tc->snd_una_max, last_hole->end))
963 {
964 if (seq_geq (last_hole->start, sb->high_sacked))
965 {
966 last_hole->end = tc->snd_una_max;
967 }
968 /* New hole after high sacked block */
969 else if (seq_lt (sb->high_sacked, tc->snd_una_max))
970 {
971 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
972 tc->snd_una_max);
973 }
974 }
975 /* Keep track of max byte sacked for when the last hole
Florin Corasf03a59a2017-06-09 21:07:32 -0700976 * is acked */
977 if (seq_gt (tmp.end, sb->high_sacked))
978 sb->high_sacked = tmp.end;
Dave Barach68b0fb02017-02-28 15:15:56 -0500979 }
980
981 /* Walk the holes with the SACK blocks */
982 hole = pool_elt_at_index (sb->holes, sb->head);
Florin Coras93992a92017-05-24 18:03:56 -0700983 while (hole && blk_index < vec_len (tc->rcv_opts.sacks))
Dave Barach68b0fb02017-02-28 15:15:56 -0500984 {
Florin Coras93992a92017-05-24 18:03:56 -0700985 blk = &tc->rcv_opts.sacks[blk_index];
Dave Barach68b0fb02017-02-28 15:15:56 -0500986 if (seq_leq (blk->start, hole->start))
987 {
988 /* Block covers hole. Remove hole */
989 if (seq_geq (blk->end, hole->end))
990 {
991 next_hole = scoreboard_next_hole (sb, hole);
992
Florin Corasf03a59a2017-06-09 21:07:32 -0700993 /* Byte accounting: snd_una needs to be advanced */
994 if (blk->end == ack)
Dave Barach68b0fb02017-02-28 15:15:56 -0500995 {
Florin Corasf03a59a2017-06-09 21:07:32 -0700996 if (next_hole)
Florin Coras06d11012017-05-17 14:21:51 -0700997 {
Florin Corasf03a59a2017-06-09 21:07:32 -0700998 if (seq_lt (ack, next_hole->start))
999 sb->snd_una_adv = next_hole->start - ack;
1000 sb->last_bytes_delivered +=
1001 next_hole->start - hole->end;
Florin Coras06d11012017-05-17 14:21:51 -07001002 }
Florin Coras3eb50622017-07-13 01:24:57 -04001003 else
Florin Coras06d11012017-05-17 14:21:51 -07001004 {
Dave Barach2c25a622017-06-26 11:35:07 -04001005 ASSERT (seq_geq (sb->high_sacked, ack));
Florin Coras93992a92017-05-24 18:03:56 -07001006 sb->snd_una_adv = sb->high_sacked - ack;
Florin Corasf03a59a2017-06-09 21:07:32 -07001007 sb->last_bytes_delivered += sb->high_sacked - hole->end;
Florin Coras06d11012017-05-17 14:21:51 -07001008 }
1009 }
1010
Dave Barach68b0fb02017-02-28 15:15:56 -05001011 scoreboard_remove_hole (sb, hole);
1012 hole = next_hole;
1013 }
Florin Coras6792ec02017-03-13 03:49:51 -07001014 /* Partial 'head' overlap */
Dave Barach68b0fb02017-02-28 15:15:56 -05001015 else
1016 {
Florin Coras6792ec02017-03-13 03:49:51 -07001017 if (seq_gt (blk->end, hole->start))
1018 {
Florin Coras6792ec02017-03-13 03:49:51 -07001019 hole->start = blk->end;
1020 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001021 blk_index++;
1022 }
1023 }
1024 else
1025 {
1026 /* Hole must be split */
Florin Coras6792ec02017-03-13 03:49:51 -07001027 if (seq_lt (blk->end, hole->end))
Dave Barach68b0fb02017-02-28 15:15:56 -05001028 {
Florin Coras6792ec02017-03-13 03:49:51 -07001029 hole_index = scoreboard_hole_index (sb, hole);
Florin Coras3eb50622017-07-13 01:24:57 -04001030 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1031 hole->end);
Florin Coras6792ec02017-03-13 03:49:51 -07001032
1033 /* Pool might've moved */
1034 hole = scoreboard_get_hole (sb, hole_index);
1035 hole->end = blk->start;
Dave Barach68b0fb02017-02-28 15:15:56 -05001036 blk_index++;
Florin Coras3eb50622017-07-13 01:24:57 -04001037 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
Dave Barach68b0fb02017-02-28 15:15:56 -05001038 }
Florin Corasf03a59a2017-06-09 21:07:32 -07001039 else if (seq_lt (blk->start, hole->end))
Dave Barach68b0fb02017-02-28 15:15:56 -05001040 {
Florin Coras6792ec02017-03-13 03:49:51 -07001041 hole->end = blk->start;
Dave Barach68b0fb02017-02-28 15:15:56 -05001042 }
Florin Coras93992a92017-05-24 18:03:56 -07001043 hole = scoreboard_next_hole (sb, hole);
Dave Barach68b0fb02017-02-28 15:15:56 -05001044 }
1045 }
Florin Coras6792ec02017-03-13 03:49:51 -07001046
Florin Corasecbd20b2018-10-17 23:34:54 -07001047 if (pool_elts (sb->holes) == 1)
1048 {
1049 hole = scoreboard_first_hole (sb);
1050 if (hole->start == ack + sb->snd_una_adv
1051 && hole->end == tc->snd_una_max)
1052 scoreboard_remove_hole (sb, hole);
1053 }
1054
Florin Corasf03a59a2017-06-09 21:07:32 -07001055 scoreboard_update_bytes (tc, sb);
1056 sb->last_sacked_bytes = sb->sacked_bytes
1057 - (old_sacked_bytes - sb->last_bytes_delivered);
Florin Corasca1c8f32018-05-23 21:01:30 -07001058 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001059 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
Florin Corasf03a59a2017-06-09 21:07:32 -07001060 || sb->sacked_bytes < tc->snd_una_max - seq_max (tc->snd_una, ack));
1061 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_una_max
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001062 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
Dave Barach2c25a622017-06-26 11:35:07 -04001063 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1064 || sb->holes[sb->head].start == ack + sb->snd_una_adv);
Florin Corasca1c8f32018-05-23 21:01:30 -07001065 TCP_EVT_DBG (TCP_EVT_CC_SCOREBOARD, tc);
Dave Barach68b0fb02017-02-28 15:15:56 -05001066}
1067
Florin Coras93992a92017-05-24 18:03:56 -07001068/**
1069 * Try to update snd_wnd based on feedback received from peer.
Dave Barach68b0fb02017-02-28 15:15:56 -05001070 *
Florin Coras93992a92017-05-24 18:03:56 -07001071 * If successful, and new window is 'effectively' 0, activate persist
1072 * timer.
1073 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001074static void
1075tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1076{
Florin Coras93992a92017-05-24 18:03:56 -07001077 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1078 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
Florin Coras6792ec02017-03-13 03:49:51 -07001079 if (seq_lt (tc->snd_wl1, seq)
1080 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
Dave Barach68b0fb02017-02-28 15:15:56 -05001081 {
1082 tc->snd_wnd = snd_wnd;
1083 tc->snd_wl1 = seq;
1084 tc->snd_wl2 = ack;
Florin Coras6792ec02017-03-13 03:49:51 -07001085 TCP_EVT_DBG (TCP_EVT_SND_WND, tc);
Florin Coras3e350af2017-03-30 02:54:28 -07001086
Florin Coras9ece3c02018-11-05 11:06:53 -08001087 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
Florin Corasbb292f42017-05-19 09:49:19 -07001088 {
Florin Coras93992a92017-05-24 18:03:56 -07001089 /* Set persist timer if not set and we just got 0 wnd */
1090 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1091 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
Florin Corasbb292f42017-05-19 09:49:19 -07001092 tcp_persist_timer_set (tc);
1093 }
Florin Coras3e350af2017-03-30 02:54:28 -07001094 else
Florin Coras93992a92017-05-24 18:03:56 -07001095 {
1096 tcp_persist_timer_reset (tc);
Florin Coras9ece3c02018-11-05 11:06:53 -08001097 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
Florin Coras93992a92017-05-24 18:03:56 -07001098 {
1099 tc->rto_boff = 0;
1100 tcp_update_rto (tc);
1101 }
1102 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001103 }
1104}
1105
Florin Corasd2aab832018-05-22 11:39:59 -07001106/**
1107 * Init loss recovery/fast recovery.
1108 *
1109 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1110 * updated in @ref tcp_cc_handle_event after fast retransmit
1111 */
Florin Coras6792ec02017-03-13 03:49:51 -07001112void
Florin Coras93992a92017-05-24 18:03:56 -07001113tcp_cc_init_congestion (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001114{
Florin Coras93992a92017-05-24 18:03:56 -07001115 tcp_fastrecovery_on (tc);
1116 tc->snd_congestion = tc->snd_una_max;
Florin Coras62166002018-04-18 16:40:55 -07001117 tc->cwnd_acc_bytes = 0;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001118 tc->snd_rxt_bytes = 0;
1119 tc->prev_ssthresh = tc->ssthresh;
1120 tc->prev_cwnd = tc->cwnd;
Dave Barach68b0fb02017-02-28 15:15:56 -05001121 tc->cc_algo->congestion (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001122 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 4);
Dave Barach68b0fb02017-02-28 15:15:56 -05001123}
1124
Florin Coras93992a92017-05-24 18:03:56 -07001125static void
1126tcp_cc_recovery_exit (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001127{
Florin Coras93992a92017-05-24 18:03:56 -07001128 tc->rto_boff = 0;
Florin Corasf1762d62017-09-24 19:43:08 -04001129 tcp_update_rto (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001130 tc->snd_rxt_ts = 0;
Florin Coras84275e92017-09-26 12:30:40 -04001131 tc->snd_nxt = tc->snd_una_max;
Florin Corasefefc6b2018-11-07 12:49:19 -08001132 tc->rtt_ts = 0;
Florin Coras93992a92017-05-24 18:03:56 -07001133 tcp_recovery_off (tc);
Florin Corasf1762d62017-09-24 19:43:08 -04001134 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 3);
Florin Coras93992a92017-05-24 18:03:56 -07001135}
Florin Coras3e350af2017-03-30 02:54:28 -07001136
Florin Coras93992a92017-05-24 18:03:56 -07001137void
1138tcp_cc_fastrecovery_exit (tcp_connection_t * tc)
1139{
Florin Coras6792ec02017-03-13 03:49:51 -07001140 tc->cc_algo->recovered (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001141 tc->snd_rxt_bytes = 0;
Florin Coras6792ec02017-03-13 03:49:51 -07001142 tc->rcv_dupacks = 0;
Florin Coras84275e92017-09-26 12:30:40 -04001143 tc->snd_nxt = tc->snd_una_max;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001144 tc->snd_rxt_bytes = 0;
Florin Corasefefc6b2018-11-07 12:49:19 -08001145 tc->rtt_ts = 0;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001146
Florin Coras93992a92017-05-24 18:03:56 -07001147 tcp_fastrecovery_off (tc);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001148 tcp_fastrecovery_first_off (tc);
Florin Corasd67f1122018-05-21 17:47:40 -07001149
Florin Corasf1762d62017-09-24 19:43:08 -04001150 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 3);
Dave Barach68b0fb02017-02-28 15:15:56 -05001151}
1152
1153static void
Florin Coras93992a92017-05-24 18:03:56 -07001154tcp_cc_congestion_undo (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001155{
Florin Coras93992a92017-05-24 18:03:56 -07001156 tc->cwnd = tc->prev_cwnd;
1157 tc->ssthresh = tc->prev_ssthresh;
1158 tc->snd_nxt = tc->snd_una_max;
1159 tc->rcv_dupacks = 0;
1160 if (tcp_in_recovery (tc))
1161 tcp_cc_recovery_exit (tc);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001162 else if (tcp_in_fastrecovery (tc))
1163 tcp_cc_fastrecovery_exit (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001164 ASSERT (tc->rto_boff == 0);
Florin Corasf1762d62017-09-24 19:43:08 -04001165 TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 5);
Florin Coras93992a92017-05-24 18:03:56 -07001166}
Dave Barach68b0fb02017-02-28 15:15:56 -05001167
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001168static inline u8
1169tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
Florin Coras93992a92017-05-24 18:03:56 -07001170{
Florin Corasf1762d62017-09-24 19:43:08 -04001171 return (tcp_in_recovery (tc) && tc->rto_boff == 1
Dave Barach2c25a622017-06-26 11:35:07 -04001172 && tc->snd_rxt_ts
Florin Coras93992a92017-05-24 18:03:56 -07001173 && tcp_opts_tstamp (&tc->rcv_opts)
1174 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1175}
1176
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001177static inline u8
1178tcp_cc_is_spurious_fast_rxt (tcp_connection_t * tc)
1179{
1180 return (tcp_in_fastrecovery (tc)
1181 && tc->cwnd > tc->ssthresh + 3 * tc->snd_mss);
1182}
1183
1184static u8
1185tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1186{
1187 return (tcp_cc_is_spurious_timeout_rxt (tc)
1188 || tcp_cc_is_spurious_fast_rxt (tc));
1189}
1190
Florin Coras0dbd5172018-06-25 16:19:34 -07001191static int
Florin Coras93992a92017-05-24 18:03:56 -07001192tcp_cc_recover (tcp_connection_t * tc)
1193{
1194 ASSERT (tcp_in_cong_recovery (tc));
1195 if (tcp_cc_is_spurious_retransmit (tc))
Dave Barach68b0fb02017-02-28 15:15:56 -05001196 {
Florin Coras93992a92017-05-24 18:03:56 -07001197 tcp_cc_congestion_undo (tc);
1198 return 1;
1199 }
1200
1201 if (tcp_in_recovery (tc))
1202 tcp_cc_recovery_exit (tc);
1203 else if (tcp_in_fastrecovery (tc))
1204 tcp_cc_fastrecovery_exit (tc);
1205
1206 ASSERT (tc->rto_boff == 0);
1207 ASSERT (!tcp_in_cong_recovery (tc));
Florin Coras3eb50622017-07-13 01:24:57 -04001208 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
Florin Coras93992a92017-05-24 18:03:56 -07001209 return 0;
1210}
1211
1212static void
1213tcp_cc_update (tcp_connection_t * tc, vlib_buffer_t * b)
1214{
Florin Coras3eb50622017-07-13 01:24:57 -04001215 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
Florin Coras93992a92017-05-24 18:03:56 -07001216
1217 /* Congestion avoidance */
Florin Corasd67f1122018-05-21 17:47:40 -07001218 tcp_cc_rcv_ack (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001219
1220 /* If a cumulative ack, make sure dupacks is 0 */
1221 tc->rcv_dupacks = 0;
1222
1223 /* When dupacks hits the threshold we only enter fast retransmit if
1224 * cumulative ack covers more than snd_congestion. Should snd_una
1225 * wrap this test may fail under otherwise valid circumstances.
1226 * Therefore, proactively update snd_congestion when wrap detected. */
1227 if (PREDICT_FALSE
1228 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1229 && seq_gt (tc->snd_congestion, tc->snd_una)))
1230 tc->snd_congestion = tc->snd_una - 1;
1231}
1232
1233static u8
1234tcp_should_fastrecover_sack (tcp_connection_t * tc)
1235{
1236 return (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss < tc->sack_sb.sacked_bytes;
1237}
1238
1239static u8
1240tcp_should_fastrecover (tcp_connection_t * tc)
1241{
1242 return (tc->rcv_dupacks == TCP_DUPACK_THRESHOLD
1243 || tcp_should_fastrecover_sack (tc));
1244}
1245
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001246void
Florin Corasbe72ae62018-11-01 11:23:03 -07001247tcp_program_fastretransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001248{
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001249 if (!(tc->flags & TCP_CONN_FRXT_PENDING))
1250 {
1251 vec_add1 (wrk->pending_fast_rxt, tc->c_c_index);
1252 tc->flags |= TCP_CONN_FRXT_PENDING;
1253 }
1254}
1255
1256void
Florin Corasbe72ae62018-11-01 11:23:03 -07001257tcp_do_fastretransmits (tcp_worker_ctx_t * wrk)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001258{
Florin Corasbe72ae62018-11-01 11:23:03 -07001259 u32 *ongoing_fast_rxt, burst_bytes, sent_bytes, thread_index;
Florin Corase55a6d72018-10-31 23:09:22 -07001260 u32 max_burst_size, burst_size, n_segs = 0, n_segs_now;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001261 tcp_connection_t *tc;
Florin Corase55a6d72018-10-31 23:09:22 -07001262 u64 last_cpu_time;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001263 int i;
1264
Florin Corase55a6d72018-10-31 23:09:22 -07001265 if (vec_len (wrk->pending_fast_rxt) == 0
1266 && vec_len (wrk->postponed_fast_rxt) == 0)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001267 return;
1268
Florin Corasbe72ae62018-11-01 11:23:03 -07001269 thread_index = wrk->vm->thread_index;
Florin Corase55a6d72018-10-31 23:09:22 -07001270 last_cpu_time = wrk->vm->clib_time.last_cpu_time;
1271 ongoing_fast_rxt = wrk->ongoing_fast_rxt;
1272 vec_append (ongoing_fast_rxt, wrk->postponed_fast_rxt);
1273 vec_append (ongoing_fast_rxt, wrk->pending_fast_rxt);
1274
1275 _vec_len (wrk->postponed_fast_rxt) = 0;
1276 _vec_len (wrk->pending_fast_rxt) = 0;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001277
Florin Coras776f3d82018-11-02 08:23:58 -07001278 max_burst_size = VLIB_FRAME_SIZE / vec_len (ongoing_fast_rxt);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001279 max_burst_size = clib_max (max_burst_size, 1);
1280
Florin Corase55a6d72018-10-31 23:09:22 -07001281 for (i = 0; i < vec_len (ongoing_fast_rxt); i++)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001282 {
Florin Corase55a6d72018-10-31 23:09:22 -07001283 if (n_segs >= VLIB_FRAME_SIZE)
1284 {
1285 vec_add1 (wrk->postponed_fast_rxt, ongoing_fast_rxt[i]);
1286 continue;
1287 }
1288
1289 tc = tcp_connection_get (ongoing_fast_rxt[i], thread_index);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001290 tc->flags &= ~TCP_CONN_FRXT_PENDING;
1291
1292 if (!tcp_in_fastrecovery (tc))
1293 continue;
1294
Florin Corase55a6d72018-10-31 23:09:22 -07001295 burst_size = clib_min (max_burst_size, VLIB_FRAME_SIZE - n_segs);
1296 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection,
1297 last_cpu_time);
1298 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1299 if (!burst_size)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001300 {
Florin Corasbe72ae62018-11-01 11:23:03 -07001301 tcp_program_fastretransmit (wrk, tc);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001302 continue;
1303 }
1304
Florin Corasbe72ae62018-11-01 11:23:03 -07001305 n_segs_now = tcp_fast_retransmit (wrk, tc, burst_size);
Florin Corase55a6d72018-10-31 23:09:22 -07001306 sent_bytes = clib_min (n_segs_now * tc->snd_mss, burst_bytes);
1307 transport_connection_tx_pacer_update_bytes (&tc->connection,
1308 sent_bytes);
Florin Corase55a6d72018-10-31 23:09:22 -07001309 n_segs += n_segs_now;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001310 }
Florin Corase55a6d72018-10-31 23:09:22 -07001311 _vec_len (ongoing_fast_rxt) = 0;
1312 wrk->ongoing_fast_rxt = ongoing_fast_rxt;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001313}
1314
Florin Corasf03a59a2017-06-09 21:07:32 -07001315/**
1316 * One function to rule them all ... and in the darkness bind them
1317 */
Florin Coras93992a92017-05-24 18:03:56 -07001318static void
1319tcp_cc_handle_event (tcp_connection_t * tc, u32 is_dack)
1320{
Florin Corasf03a59a2017-06-09 21:07:32 -07001321 u32 rxt_delivered;
1322
Florin Corasca1c8f32018-05-23 21:01:30 -07001323 if (tcp_in_fastrecovery (tc) && tcp_opts_sack_permitted (&tc->rcv_opts))
1324 {
1325 if (tc->bytes_acked)
1326 goto partial_ack;
Florin Corasbe72ae62018-11-01 11:23:03 -07001327 tcp_program_fastretransmit (tcp_get_worker (tc->c_thread_index), tc);
Florin Corasca1c8f32018-05-23 21:01:30 -07001328 return;
1329 }
Florin Coras93992a92017-05-24 18:03:56 -07001330 /*
1331 * Duplicate ACK. Check if we should enter fast recovery, or if already in
1332 * it account for the bytes that left the network.
1333 */
Florin Corasca1c8f32018-05-23 21:01:30 -07001334 else if (is_dack && !tcp_in_recovery (tc))
Florin Coras93992a92017-05-24 18:03:56 -07001335 {
Florin Corasd2aab832018-05-22 11:39:59 -07001336 TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc, 1);
Florin Coras93992a92017-05-24 18:03:56 -07001337 ASSERT (tc->snd_una != tc->snd_una_max
1338 || tc->sack_sb.last_sacked_bytes);
Dave Barach2c25a622017-06-26 11:35:07 -04001339
Florin Coras93992a92017-05-24 18:03:56 -07001340 tc->rcv_dupacks++;
1341
Florin Corasd2aab832018-05-22 11:39:59 -07001342 /* Pure duplicate ack. If some data got acked, it's handled lower */
Florin Coras93992a92017-05-24 18:03:56 -07001343 if (tc->rcv_dupacks > TCP_DUPACK_THRESHOLD && !tc->bytes_acked)
Dave Barach68b0fb02017-02-28 15:15:56 -05001344 {
Florin Coras93992a92017-05-24 18:03:56 -07001345 ASSERT (tcp_in_fastrecovery (tc));
Florin Coras93992a92017-05-24 18:03:56 -07001346 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
1347 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001348 }
Florin Coras93992a92017-05-24 18:03:56 -07001349 else if (tcp_should_fastrecover (tc))
Dave Barach68b0fb02017-02-28 15:15:56 -05001350 {
Florin Corasc44a5582018-11-01 16:30:54 -07001351 u32 pacer_wnd;
1352
Florin Corasd2aab832018-05-22 11:39:59 -07001353 ASSERT (!tcp_in_fastrecovery (tc));
Florin Coras93992a92017-05-24 18:03:56 -07001354
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001355 /* Heuristic to catch potential late dupacks
1356 * after fast retransmit exits */
1357 if (is_dack && tc->snd_una == tc->snd_congestion
1358 && timestamp_leq (tc->rcv_opts.tsecr, tc->tsecr_last_ack))
Florin Coras93992a92017-05-24 18:03:56 -07001359 {
1360 tc->rcv_dupacks = 0;
1361 return;
1362 }
1363
1364 tcp_cc_init_congestion (tc);
1365 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
1366
Florin Coras3eb50622017-07-13 01:24:57 -04001367 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Corase55a6d72018-10-31 23:09:22 -07001368 {
1369 tc->cwnd = tc->ssthresh;
1370 scoreboard_init_high_rxt (&tc->sack_sb, tc->snd_una);
Florin Corase55a6d72018-10-31 23:09:22 -07001371 }
1372 else
1373 {
1374 /* Post retransmit update cwnd to ssthresh and account for the
1375 * three segments that have left the network and should've been
1376 * buffered at the receiver XXX */
1377 tc->cwnd = tc->ssthresh + 3 * tc->snd_mss;
1378 }
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001379
Florin Coras36ee9f12018-11-02 12:52:10 -07001380 /* Constrain rate until we get a partial ack */
Florin Corasc44a5582018-11-01 16:30:54 -07001381 pacer_wnd = clib_max (0.1 * tc->cwnd, 2 * tc->snd_mss);
1382 tcp_connection_tx_pacer_reset (tc, pacer_wnd,
1383 0 /* start bucket */ );
Florin Corasbe72ae62018-11-01 11:23:03 -07001384 tcp_program_fastretransmit (tcp_get_worker (tc->c_thread_index),
1385 tc);
Florin Coras93992a92017-05-24 18:03:56 -07001386 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001387 }
Florin Coras93992a92017-05-24 18:03:56 -07001388 else if (!tc->bytes_acked
1389 || (tc->bytes_acked && !tcp_in_cong_recovery (tc)))
1390 {
1391 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
1392 return;
1393 }
1394 else
1395 goto partial_ack;
1396 }
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001397 /* Don't allow entry in fast recovery if still in recovery, for now */
1398 else if (0 && is_dack && tcp_in_recovery (tc))
1399 {
1400 /* If of of the two conditions lower hold, reset dupacks because
1401 * we're probably after timeout (RFC6582 heuristics).
1402 * If Cumulative ack does not cover more than congestion threshold,
1403 * and:
1404 * 1) The following doesn't hold: The congestion window is greater
1405 * than SMSS bytes and the difference between highest_ack
1406 * and prev_highest_ack is at most 4*SMSS bytes
1407 * 2) Echoed timestamp in the last non-dup ack does not equal the
1408 * stored timestamp
1409 */
1410 if (seq_leq (tc->snd_una, tc->snd_congestion)
1411 && ((!(tc->cwnd > tc->snd_mss
1412 && tc->bytes_acked <= 4 * tc->snd_mss))
1413 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1414 {
1415 tc->rcv_dupacks = 0;
1416 return;
1417 }
1418 }
Florin Coras93992a92017-05-24 18:03:56 -07001419
Florin Coras93992a92017-05-24 18:03:56 -07001420 if (!tc->bytes_acked)
1421 return;
1422
1423partial_ack:
Florin Corasd2aab832018-05-22 11:39:59 -07001424 TCP_EVT_DBG (TCP_EVT_CC_PACK, tc);
1425
Florin Coras93992a92017-05-24 18:03:56 -07001426 /*
1427 * Legitimate ACK. 1) See if we can exit recovery
1428 */
Florin Coras93992a92017-05-24 18:03:56 -07001429
Florin Corasefefc6b2018-11-07 12:49:19 -08001430 /* Update the pacing rate. For the first partial ack we move from
1431 * the artificially constrained rate to the one after congestion */
1432 tcp_connection_tx_pacer_update (tc);
1433
Florin Coras93992a92017-05-24 18:03:56 -07001434 if (seq_geq (tc->snd_una, tc->snd_congestion))
1435 {
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001436 tcp_retransmit_timer_update (tc);
1437
Florin Coras93992a92017-05-24 18:03:56 -07001438 /* If spurious return, we've already updated everything */
1439 if (tcp_cc_recover (tc))
Florin Corasf03a59a2017-06-09 21:07:32 -07001440 {
1441 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1442 return;
1443 }
Florin Coras93992a92017-05-24 18:03:56 -07001444
1445 tc->snd_nxt = tc->snd_una_max;
1446
1447 /* Treat as congestion avoidance ack */
Florin Corasd67f1122018-05-21 17:47:40 -07001448 tcp_cc_rcv_ack (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001449 return;
1450 }
1451
1452 /*
1453 * Legitimate ACK. 2) If PARTIAL ACK try to retransmit
1454 */
Florin Coras93992a92017-05-24 18:03:56 -07001455
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001456 /* XXX limit this only to first partial ack? */
Florin Coras2e31cc32018-09-25 14:00:34 -07001457 tcp_retransmit_timer_update (tc);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001458
Florin Coras93992a92017-05-24 18:03:56 -07001459 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
Florin Corasd2aab832018-05-22 11:39:59 -07001460 * reset dupacks to 0. Also needed if in congestion recovery */
Florin Coras93992a92017-05-24 18:03:56 -07001461 tc->rcv_dupacks = 0;
1462
Florin Coras93992a92017-05-24 18:03:56 -07001463 /* Post RTO timeout don't try anything fancy */
1464 if (tcp_in_recovery (tc))
Florin Corasd2aab832018-05-22 11:39:59 -07001465 {
Florin Corasd67f1122018-05-21 17:47:40 -07001466 tcp_cc_rcv_ack (tc);
Florin Coras3ec66b02018-08-23 16:27:05 -07001467 transport_add_tx_event (&tc->connection);
Florin Corasd2aab832018-05-22 11:39:59 -07001468 return;
1469 }
Florin Coras93992a92017-05-24 18:03:56 -07001470
1471 /* Remove retransmitted bytes that have been delivered */
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001472 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Coras93992a92017-05-24 18:03:56 -07001473 {
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001474 ASSERT (tc->bytes_acked + tc->sack_sb.snd_una_adv
1475 >= tc->sack_sb.last_bytes_delivered
1476 || (tc->flags & TCP_CONN_FINSNT));
1477
Florin Coras93992a92017-05-24 18:03:56 -07001478 /* If we have sacks and we haven't gotten an ack beyond high_rxt,
1479 * remove sacked bytes delivered */
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001480 if (seq_lt (tc->snd_una, tc->sack_sb.high_rxt))
1481 {
1482 rxt_delivered = tc->bytes_acked + tc->sack_sb.snd_una_adv
1483 - tc->sack_sb.last_bytes_delivered;
1484 ASSERT (tc->snd_rxt_bytes >= rxt_delivered);
1485 tc->snd_rxt_bytes -= rxt_delivered;
1486 }
1487 else
1488 {
1489 /* Apparently all retransmitted holes have been acked */
1490 tc->snd_rxt_bytes = 0;
Florin Coras36ee9f12018-11-02 12:52:10 -07001491 tc->sack_sb.high_rxt = tc->snd_una;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001492 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001493 }
1494 else
1495 {
Florin Coras36ee9f12018-11-02 12:52:10 -07001496 tcp_fastrecovery_first_on (tc);
1497 /* Reuse last bytes delivered to track total bytes acked */
1498 tc->sack_sb.last_bytes_delivered += tc->bytes_acked;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001499 if (tc->snd_rxt_bytes > tc->bytes_acked)
1500 tc->snd_rxt_bytes -= tc->bytes_acked;
1501 else
1502 tc->snd_rxt_bytes = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001503 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001504
Florin Coras93992a92017-05-24 18:03:56 -07001505 tc->cc_algo->rcv_cong_ack (tc, TCP_CC_PARTIALACK);
Dave Barach68b0fb02017-02-28 15:15:56 -05001506
Florin Coras93992a92017-05-24 18:03:56 -07001507 /*
1508 * Since this was a partial ack, try to retransmit some more data
1509 */
Florin Corasbe72ae62018-11-01 11:23:03 -07001510 tcp_program_fastretransmit (tcp_get_worker (tc->c_thread_index), tc);
Dave Barach68b0fb02017-02-28 15:15:56 -05001511}
1512
Florin Coras93992a92017-05-24 18:03:56 -07001513/**
1514 * Process incoming ACK
1515 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001516static int
Florin Coras9ece3c02018-11-05 11:06:53 -08001517tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
Florin Coras7ac053b2018-11-05 15:57:21 -08001518 tcp_header_t * th, u32 * error)
Dave Barach68b0fb02017-02-28 15:15:56 -05001519{
Florin Coras93992a92017-05-24 18:03:56 -07001520 u32 prev_snd_wnd, prev_snd_una;
1521 u8 is_dack;
Dave Barach68b0fb02017-02-28 15:15:56 -05001522
Florin Corasf03a59a2017-06-09 21:07:32 -07001523 TCP_EVT_DBG (TCP_EVT_CC_STAT, tc);
1524
Florin Coras6792ec02017-03-13 03:49:51 -07001525 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
Florin Coras93992a92017-05-24 18:03:56 -07001526 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
Dave Barach68b0fb02017-02-28 15:15:56 -05001527 {
Florin Corasca1c8f32018-05-23 21:01:30 -07001528 /* When we entered recovery, we reset snd_nxt to snd_una. Seems peer
1529 * still has the data so accept the ack */
1530 if (tcp_in_recovery (tc)
Florin Coras3ec66b02018-08-23 16:27:05 -07001531 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_congestion))
Florin Corasca1c8f32018-05-23 21:01:30 -07001532 {
Florin Coras3ec66b02018-08-23 16:27:05 -07001533 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1534 if (seq_gt (tc->snd_nxt, tc->snd_una_max))
1535 tc->snd_una_max = tc->snd_nxt;
Florin Corasca1c8f32018-05-23 21:01:30 -07001536 goto process_ack;
1537 }
1538
Florin Coras6792ec02017-03-13 03:49:51 -07001539 /* If we have outstanding data and this is within the window, accept it,
1540 * probably retransmit has timed out. Otherwise ACK segment and then
1541 * drop it */
1542 if (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max))
1543 {
Florin Coras7ac053b2018-11-05 15:57:21 -08001544 tcp_program_ack (wrk, tc);
Florin Coras36ee9f12018-11-02 12:52:10 -07001545 *error = TCP_ERROR_ACK_FUTURE;
Florin Coras6792ec02017-03-13 03:49:51 -07001546 TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 0,
1547 vnet_buffer (b)->tcp.ack_number);
1548 return -1;
1549 }
1550
Florin Coras6792ec02017-03-13 03:49:51 -07001551 TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 2,
1552 vnet_buffer (b)->tcp.ack_number);
Florin Coras3e350af2017-03-30 02:54:28 -07001553
1554 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
Dave Barach68b0fb02017-02-28 15:15:56 -05001555 }
1556
Florin Coras6792ec02017-03-13 03:49:51 -07001557 /* If old ACK, probably it's an old dupack */
Florin Coras93992a92017-05-24 18:03:56 -07001558 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
Dave Barach68b0fb02017-02-28 15:15:56 -05001559 {
1560 *error = TCP_ERROR_ACK_OLD;
Florin Coras6792ec02017-03-13 03:49:51 -07001561 TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 1,
1562 vnet_buffer (b)->tcp.ack_number);
1563 if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
Florin Corasca1c8f32018-05-23 21:01:30 -07001564 tcp_cc_handle_event (tc, 1);
Florin Corasc28764f2017-04-26 00:08:42 -07001565 /* Don't drop yet */
1566 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001567 }
1568
Florin Coras93992a92017-05-24 18:03:56 -07001569 /*
1570 * Looks okay, process feedback
1571 */
Florin Corasca1c8f32018-05-23 21:01:30 -07001572process_ack:
Florin Coras93992a92017-05-24 18:03:56 -07001573 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05001574 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1575
Florin Coras93992a92017-05-24 18:03:56 -07001576 prev_snd_wnd = tc->snd_wnd;
1577 prev_snd_una = tc->snd_una;
1578 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1579 vnet_buffer (b)->tcp.ack_number,
1580 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1581 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1582 tc->snd_una = vnet_buffer (b)->tcp.ack_number + tc->sack_sb.snd_una_adv;
1583 tcp_validate_txf_size (tc, tc->bytes_acked);
Dave Barach68b0fb02017-02-28 15:15:56 -05001584
Florin Coras93992a92017-05-24 18:03:56 -07001585 if (tc->bytes_acked)
Florin Coras9ece3c02018-11-05 11:06:53 -08001586 {
1587 tcp_program_dequeue (wrk, tc);
1588 tcp_update_rtt (tc, vnet_buffer (b)->tcp.ack_number);
1589 }
Florin Coras93992a92017-05-24 18:03:56 -07001590
Florin Coras6534b7a2017-07-18 05:38:03 -04001591 TCP_EVT_DBG (TCP_EVT_ACK_RCVD, tc);
1592
Florin Coras93992a92017-05-24 18:03:56 -07001593 /*
1594 * Check if we have congestion event
1595 */
1596
1597 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
Dave Barach68b0fb02017-02-28 15:15:56 -05001598 {
Florin Coras93992a92017-05-24 18:03:56 -07001599 tcp_cc_handle_event (tc, is_dack);
Florin Corasb2215d62017-08-01 16:56:58 -07001600 if (!tcp_in_cong_recovery (tc))
1601 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001602 *error = TCP_ERROR_ACK_DUP;
Florin Corasca09d072018-10-01 18:31:02 -07001603 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1604 return 0;
1605 return -1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001606 }
1607
Florin Coras6792ec02017-03-13 03:49:51 -07001608 /*
Florin Coras93992a92017-05-24 18:03:56 -07001609 * Update congestion control (slow start/congestion avoidance)
Florin Coras6792ec02017-03-13 03:49:51 -07001610 */
Florin Coras93992a92017-05-24 18:03:56 -07001611 tcp_cc_update (tc, b);
Florin Coras00cd22d2018-04-18 13:20:18 -07001612 *error = TCP_ERROR_ACK_OK;
Dave Barach68b0fb02017-02-28 15:15:56 -05001613 return 0;
1614}
1615
Florin Corasb11175d2018-11-09 14:34:08 -08001616static void
1617tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1618{
1619 if (!tcp_disconnect_pending (tc))
1620 {
1621 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1622 tcp_disconnect_pending_on (tc);
1623 }
1624}
1625
1626static void
1627tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1628{
1629 u32 thread_index, *pending_disconnects;
1630 tcp_connection_t *tc;
1631 int i;
1632
1633 if (!vec_len (wrk->pending_disconnects))
1634 return;
1635
1636 thread_index = wrk->vm->thread_index;
1637 pending_disconnects = wrk->pending_disconnects;
1638 for (i = 0; i < vec_len (pending_disconnects); i++)
1639 {
1640 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1641 tcp_disconnect_pending_off (tc);
1642 stream_session_disconnect_notify (&tc->connection);
1643 }
1644 _vec_len (wrk->pending_disconnects) = 0;
1645}
1646
1647static void
1648tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1649 u32 * error)
1650{
1651 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1652 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1653 /* Account for the FIN if nothing else was received */
1654 if (vnet_buffer (b)->tcp.data_len == 0)
1655 tc->rcv_nxt += 1;
1656 tcp_program_ack (wrk, tc);
1657 tc->state = TCP_STATE_CLOSE_WAIT;
1658 tcp_program_disconnect (wrk, tc);
1659 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
1660 TCP_EVT_DBG (TCP_EVT_FIN_RCVD, tc);
1661 *error = TCP_ERROR_FIN_RCVD;
1662}
1663
Florin Coras3eb50622017-07-13 01:24:57 -04001664static u8
1665tcp_sack_vector_is_sane (sack_block_t * sacks)
1666{
1667 int i;
1668 for (i = 1; i < vec_len (sacks); i++)
1669 {
1670 if (sacks[i - 1].end == sacks[i].start)
1671 return 0;
1672 }
1673 return 1;
1674}
1675
Dave Barach68b0fb02017-02-28 15:15:56 -05001676/**
1677 * Build SACK list as per RFC2018.
1678 *
1679 * Makes sure the first block contains the segment that generated the current
1680 * ACK and the following ones are the ones most recently reported in SACK
1681 * blocks.
1682 *
1683 * @param tc TCP connection for which the SACK list is updated
1684 * @param start Start sequence number of the newest SACK block
1685 * @param end End sequence of the newest SACK block
1686 */
Florin Coras45d34962017-04-25 00:05:27 -07001687void
Dave Barach68b0fb02017-02-28 15:15:56 -05001688tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1689{
Florin Coras45d34962017-04-25 00:05:27 -07001690 sack_block_t *new_list = 0, *block = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001691 int i;
Dave Barach68b0fb02017-02-28 15:15:56 -05001692
1693 /* If the first segment is ooo add it to the list. Last write might've moved
1694 * rcv_nxt over the first segment. */
1695 if (seq_lt (tc->rcv_nxt, start))
1696 {
Florin Coras45d34962017-04-25 00:05:27 -07001697 vec_add2 (new_list, block, 1);
1698 block->start = start;
1699 block->end = end;
Dave Barach68b0fb02017-02-28 15:15:56 -05001700 }
1701
1702 /* Find the blocks still worth keeping. */
1703 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1704 {
Florin Coras45d34962017-04-25 00:05:27 -07001705 /* Discard if rcv_nxt advanced beyond current block */
1706 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
Dave Barach68b0fb02017-02-28 15:15:56 -05001707 continue;
1708
Florin Coras45d34962017-04-25 00:05:27 -07001709 /* Merge or drop if segment overlapped by the new segment */
1710 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1711 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1712 {
1713 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1714 new_list[0].start = tc->snd_sacks[i].start;
1715 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1716 new_list[0].end = tc->snd_sacks[i].end;
1717 continue;
1718 }
1719
1720 /* Save to new SACK list if we have space. */
1721 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1722 {
1723 vec_add1 (new_list, tc->snd_sacks[i]);
1724 }
Florin Corasf03a59a2017-06-09 21:07:32 -07001725 else
1726 {
1727 clib_warning ("sack discarded");
1728 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001729 }
1730
Florin Coras45d34962017-04-25 00:05:27 -07001731 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
Florin Coras6792ec02017-03-13 03:49:51 -07001732
Dave Barach68b0fb02017-02-28 15:15:56 -05001733 /* Replace old vector with new one */
1734 vec_free (tc->snd_sacks);
1735 tc->snd_sacks = new_list;
Florin Coras3eb50622017-07-13 01:24:57 -04001736
1737 /* Segments should not 'touch' */
1738 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
Dave Barach68b0fb02017-02-28 15:15:56 -05001739}
1740
Florin Corasca1c8f32018-05-23 21:01:30 -07001741u32
1742tcp_sack_list_bytes (tcp_connection_t * tc)
1743{
1744 u32 bytes = 0, i;
1745 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1746 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1747 return bytes;
1748}
1749
Dave Barach68b0fb02017-02-28 15:15:56 -05001750/** Enqueue data for delivery to application */
Florin Coras0dbd5172018-06-25 16:19:34 -07001751static int
Dave Barach68b0fb02017-02-28 15:15:56 -05001752tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1753 u16 data_len)
1754{
Florin Coras1f152cd2017-08-18 19:28:03 -07001755 int written, error = TCP_ERROR_ENQUEUED;
Dave Barach68b0fb02017-02-28 15:15:56 -05001756
Dave Barach2c25a622017-06-26 11:35:07 -04001757 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
Florin Coras00cd22d2018-04-18 13:20:18 -07001758 ASSERT (data_len);
Florin Coras3cbc04b2017-10-02 00:18:51 -07001759 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1760 1 /* queue event */ , 1);
Dave Barach68b0fb02017-02-28 15:15:56 -05001761
Florin Coras6792ec02017-03-13 03:49:51 -07001762 TCP_EVT_DBG (TCP_EVT_INPUT, tc, 0, data_len, written);
1763
Dave Barach68b0fb02017-02-28 15:15:56 -05001764 /* Update rcv_nxt */
1765 if (PREDICT_TRUE (written == data_len))
1766 {
Florin Coras1f152cd2017-08-18 19:28:03 -07001767 tc->rcv_nxt += written;
Dave Barach68b0fb02017-02-28 15:15:56 -05001768 }
1769 /* If more data written than expected, account for out-of-order bytes. */
1770 else if (written > data_len)
1771 {
Florin Coras1f152cd2017-08-18 19:28:03 -07001772 tc->rcv_nxt += written;
Florin Corasca1c8f32018-05-23 21:01:30 -07001773 TCP_EVT_DBG (TCP_EVT_CC_INPUT, tc, data_len, written);
Florin Coras6792ec02017-03-13 03:49:51 -07001774 }
1775 else if (written > 0)
1776 {
1777 /* We've written something but FIFO is probably full now */
1778 tc->rcv_nxt += written;
Florin Coras1f152cd2017-08-18 19:28:03 -07001779 error = TCP_ERROR_PARTIALLY_ENQUEUED;
Dave Barach68b0fb02017-02-28 15:15:56 -05001780 }
1781 else
1782 {
Dave Barach68b0fb02017-02-28 15:15:56 -05001783 return TCP_ERROR_FIFO_FULL;
1784 }
1785
Florin Coras6792ec02017-03-13 03:49:51 -07001786 /* Update SACK list if need be */
Florin Coras93992a92017-05-24 18:03:56 -07001787 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Coras6792ec02017-03-13 03:49:51 -07001788 {
1789 /* Remove SACK blocks that have been delivered */
1790 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1791 }
1792
Florin Coras1f152cd2017-08-18 19:28:03 -07001793 return error;
Dave Barach68b0fb02017-02-28 15:15:56 -05001794}
1795
1796/** Enqueue out-of-order data */
Florin Coras0dbd5172018-06-25 16:19:34 -07001797static int
Dave Barach68b0fb02017-02-28 15:15:56 -05001798tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1799 u16 data_len)
1800{
1801 stream_session_t *s0;
Florin Coras3eb50622017-07-13 01:24:57 -04001802 int rv, offset;
Florin Coras6792ec02017-03-13 03:49:51 -07001803
Florin Corasf03a59a2017-06-09 21:07:32 -07001804 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
Florin Coras00cd22d2018-04-18 13:20:18 -07001805 ASSERT (data_len);
Dave Barach68b0fb02017-02-28 15:15:56 -05001806
Florin Corasf03a59a2017-06-09 21:07:32 -07001807 /* Enqueue out-of-order data with relative offset */
Florin Coras3cbc04b2017-10-02 00:18:51 -07001808 rv = session_enqueue_stream_connection (&tc->connection, b,
1809 vnet_buffer (b)->tcp.seq_number -
1810 tc->rcv_nxt, 0 /* queue event */ ,
1811 0);
Florin Coras6792ec02017-03-13 03:49:51 -07001812
1813 /* Nothing written */
1814 if (rv)
1815 {
1816 TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, 0);
1817 return TCP_ERROR_FIFO_FULL;
1818 }
1819
1820 TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, data_len);
Dave Barach68b0fb02017-02-28 15:15:56 -05001821
1822 /* Update SACK list if in use */
Florin Coras93992a92017-05-24 18:03:56 -07001823 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -05001824 {
1825 ooo_segment_t *newest;
1826 u32 start, end;
1827
Florin Corascea194d2017-10-02 00:18:51 -07001828 s0 = session_get (tc->c_s_index, tc->c_thread_index);
Florin Corasf6d68ed2017-05-07 19:12:02 -07001829
Dave Barach68b0fb02017-02-28 15:15:56 -05001830 /* Get the newest segment from the fifo */
1831 newest = svm_fifo_newest_ooo_segment (s0->server_rx_fifo);
Florin Corasf03a59a2017-06-09 21:07:32 -07001832 if (newest)
1833 {
Florin Coras3eb50622017-07-13 01:24:57 -04001834 offset = ooo_segment_offset (s0->server_rx_fifo, newest);
1835 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1836 start = tc->rcv_nxt + offset;
Florin Corasf03a59a2017-06-09 21:07:32 -07001837 end = start + ooo_segment_length (s0->server_rx_fifo, newest);
1838 tcp_update_sack_list (tc, start, end);
Florin Coras3eb50622017-07-13 01:24:57 -04001839 svm_fifo_newest_ooo_segment_reset (s0->server_rx_fifo);
Florin Corasca1c8f32018-05-23 21:01:30 -07001840 TCP_EVT_DBG (TCP_EVT_CC_SACKS, tc);
Florin Corasf03a59a2017-06-09 21:07:32 -07001841 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001842 }
1843
Florin Coras00cd22d2018-04-18 13:20:18 -07001844 return TCP_ERROR_ENQUEUED_OOO;
Dave Barach68b0fb02017-02-28 15:15:56 -05001845}
1846
1847/**
Florin Coras6792ec02017-03-13 03:49:51 -07001848 * Check if ACK could be delayed. If ack can be delayed, it should return
1849 * true for a full frame. If we're always acking return 0.
Dave Barach68b0fb02017-02-28 15:15:56 -05001850 */
1851always_inline int
1852tcp_can_delack (tcp_connection_t * tc)
1853{
Florin Coras6792ec02017-03-13 03:49:51 -07001854 /* Send ack if ... */
1855 if (TCP_ALWAYS_ACK
1856 /* just sent a rcv wnd 0 */
1857 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0
1858 /* constrained to send ack */
1859 || (tc->flags & TCP_CONN_SNDACK) != 0
1860 /* we're almost out of tx wnd */
Florin Corasca1c8f32018-05-23 21:01:30 -07001861 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
Florin Coras6792ec02017-03-13 03:49:51 -07001862 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05001863
Florin Coras6792ec02017-03-13 03:49:51 -07001864 return 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001865}
1866
1867static int
Florin Corasb2215d62017-08-01 16:56:58 -07001868tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1869{
Florin Coras1f152cd2017-08-18 19:28:03 -07001870 u32 discard, first = b->current_length;
Florin Corasb2215d62017-08-01 16:56:58 -07001871 vlib_main_t *vm = vlib_get_main ();
1872
Florin Coras1f152cd2017-08-18 19:28:03 -07001873 /* Handle multi-buffer segments */
Florin Corasb2215d62017-08-01 16:56:58 -07001874 if (n_bytes_to_drop > b->current_length)
1875 {
1876 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1877 return -1;
1878 do
1879 {
1880 discard = clib_min (n_bytes_to_drop, b->current_length);
1881 vlib_buffer_advance (b, discard);
1882 b = vlib_get_buffer (vm, b->next_buffer);
1883 n_bytes_to_drop -= discard;
1884 }
1885 while (n_bytes_to_drop);
Florin Coras1f152cd2017-08-18 19:28:03 -07001886 if (n_bytes_to_drop > first)
1887 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
Florin Corasb2215d62017-08-01 16:56:58 -07001888 }
Florin Coras1f152cd2017-08-18 19:28:03 -07001889 else
1890 vlib_buffer_advance (b, n_bytes_to_drop);
1891 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
Florin Corasb2215d62017-08-01 16:56:58 -07001892 return 0;
1893}
1894
Florin Coras00cd22d2018-04-18 13:20:18 -07001895/**
1896 * Receive buffer for connection and handle acks
1897 *
1898 * It handles both in order or out-of-order data.
1899 */
Florin Corasb2215d62017-08-01 16:56:58 -07001900static int
Florin Coras7ac053b2018-11-05 15:57:21 -08001901tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1902 vlib_buffer_t * b)
Dave Barach68b0fb02017-02-28 15:15:56 -05001903{
Florin Coras00cd22d2018-04-18 13:20:18 -07001904 u32 error, n_bytes_to_drop, n_data_bytes;
Florin Coras6534b7a2017-07-18 05:38:03 -04001905
1906 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1907 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1908 ASSERT (n_data_bytes);
Dave Barach68b0fb02017-02-28 15:15:56 -05001909
1910 /* Handle out-of-order data */
1911 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1912 {
Florin Coras6792ec02017-03-13 03:49:51 -07001913 /* Old sequence numbers allowed through because they overlapped
1914 * the rx window */
1915 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
Dave Barach68b0fb02017-02-28 15:15:56 -05001916 {
Florin Coras00cd22d2018-04-18 13:20:18 -07001917 /* Completely in the past (possible retransmit). Ack
1918 * retransmissions since we may not have any data to send */
Florin Corasf03a59a2017-06-09 21:07:32 -07001919 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
Florin Coras6534b7a2017-07-18 05:38:03 -04001920 {
Florin Coras7ac053b2018-11-05 15:57:21 -08001921 tcp_program_ack (wrk, tc);
Florin Coras00cd22d2018-04-18 13:20:18 -07001922 error = TCP_ERROR_SEGMENT_OLD;
Florin Coras6534b7a2017-07-18 05:38:03 -04001923 goto done;
1924 }
Dave Barach259cdae2017-05-15 16:27:05 -04001925
Florin Coras00cd22d2018-04-18 13:20:18 -07001926 /* Chop off the bytes in the past and see if what is left
1927 * can be enqueued in order */
Florin Corasdb84e572017-05-09 18:54:52 -07001928 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1929 n_data_bytes -= n_bytes_to_drop;
Dave Barach2c25a622017-06-26 11:35:07 -04001930 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
Florin Corasb2215d62017-08-01 16:56:58 -07001931 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
Florin Coras00cd22d2018-04-18 13:20:18 -07001932 {
1933 error = TCP_ERROR_SEGMENT_OLD;
Florin Coras00cd22d2018-04-18 13:20:18 -07001934 goto done;
1935 }
Florin Corasdb84e572017-05-09 18:54:52 -07001936 goto in_order;
Dave Barach68b0fb02017-02-28 15:15:56 -05001937 }
1938
Florin Coras00cd22d2018-04-18 13:20:18 -07001939 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
Florin Coras6792ec02017-03-13 03:49:51 -07001940 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
Florin Coras7ac053b2018-11-05 15:57:21 -08001941 tcp_program_dupack (wrk, tc);
Florin Corasca1c8f32018-05-23 21:01:30 -07001942 TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
Dave Barach68b0fb02017-02-28 15:15:56 -05001943 goto done;
1944 }
1945
Florin Corasdb84e572017-05-09 18:54:52 -07001946in_order:
1947
Dave Barach68b0fb02017-02-28 15:15:56 -05001948 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1949 * segments can be enqueued after fifo tail offset changes. */
1950 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
Florin Coras3e350af2017-03-30 02:54:28 -07001951 if (tcp_can_delack (tc))
Dave Barach68b0fb02017-02-28 15:15:56 -05001952 {
Florin Coras6792ec02017-03-13 03:49:51 -07001953 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1954 tcp_timer_set (tc, TCP_TIMER_DELACK, TCP_DELACK_TIME);
Florin Coras3e350af2017-03-30 02:54:28 -07001955 goto done;
Dave Barach68b0fb02017-02-28 15:15:56 -05001956 }
1957
Florin Coras7ac053b2018-11-05 15:57:21 -08001958 tcp_program_ack (wrk, tc);
Florin Coras3e350af2017-03-30 02:54:28 -07001959
Dave Barach68b0fb02017-02-28 15:15:56 -05001960done:
1961 return error;
1962}
1963
Clement Durand6cf260c2017-04-13 13:27:04 +02001964typedef struct
1965{
1966 tcp_header_t tcp_header;
1967 tcp_connection_t tcp_connection;
1968} tcp_rx_trace_t;
1969
Florin Coras0dbd5172018-06-25 16:19:34 -07001970static u8 *
Clement Durand6cf260c2017-04-13 13:27:04 +02001971format_tcp_rx_trace (u8 * s, va_list * args)
1972{
1973 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1974 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1975 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
Christophe Fontained3c008d2017-10-02 18:10:54 +02001976 u32 indent = format_get_indent (s);
Clement Durand6cf260c2017-04-13 13:27:04 +02001977
1978 s = format (s, "%U\n%U%U",
1979 format_tcp_header, &t->tcp_header, 128,
1980 format_white_space, indent,
Florin Corasbb292f42017-05-19 09:49:19 -07001981 format_tcp_connection, &t->tcp_connection, 1);
Clement Durand6cf260c2017-04-13 13:27:04 +02001982
1983 return s;
1984}
1985
Florin Coras0dbd5172018-06-25 16:19:34 -07001986static u8 *
Clement Durand6cf260c2017-04-13 13:27:04 +02001987format_tcp_rx_trace_short (u8 * s, va_list * args)
1988{
1989 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1990 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1991 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1992
1993 s = format (s, "%d -> %d (%U)",
Florin Coras4df38712018-06-20 12:44:16 -07001994 clib_net_to_host_u16 (t->tcp_header.dst_port),
1995 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
Florin Corasbb292f42017-05-19 09:49:19 -07001996 t->tcp_connection.state);
Clement Durand6cf260c2017-04-13 13:27:04 +02001997
1998 return s;
1999}
2000
Florin Coras4df38712018-06-20 12:44:16 -07002001static void
Florin Coras82b13a82017-04-25 11:58:06 -07002002tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
2003 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
2004{
2005 if (tc0)
2006 {
Dave Barach178cf492018-11-13 16:34:13 -05002007 clib_memcpy_fast (&t0->tcp_connection, tc0,
2008 sizeof (t0->tcp_connection));
Florin Coras82b13a82017-04-25 11:58:06 -07002009 }
2010 else
2011 {
2012 th0 = tcp_buffer_hdr (b0);
2013 }
Dave Barach178cf492018-11-13 16:34:13 -05002014 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
Florin Coras82b13a82017-04-25 11:58:06 -07002015}
2016
Florin Coras4df38712018-06-20 12:44:16 -07002017static void
2018tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2019 vlib_frame_t * frame, u8 is_ip4)
2020{
2021 u32 *from, n_left;
2022
2023 n_left = frame->n_vectors;
2024 from = vlib_frame_vector_args (frame);
2025
2026 while (n_left >= 1)
2027 {
2028 tcp_connection_t *tc0;
2029 tcp_rx_trace_t *t0;
2030 tcp_header_t *th0;
2031 vlib_buffer_t *b0;
2032 u32 bi0;
2033
2034 bi0 = from[0];
2035 b0 = vlib_get_buffer (vm, bi0);
2036
2037 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2038 {
2039 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2040 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2041 vm->thread_index);
2042 th0 = tcp_buffer_hdr (b0);
2043 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2044 }
2045
2046 from += 1;
2047 n_left -= 1;
2048 }
2049}
2050
Florin Coras6792ec02017-03-13 03:49:51 -07002051always_inline void
Florin Coras00cd22d2018-04-18 13:20:18 -07002052tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2053 u8 is_ip4, u32 evt, u32 val)
Dave Barach68b0fb02017-02-28 15:15:56 -05002054{
Florin Coras6792ec02017-03-13 03:49:51 -07002055 if (is_ip4)
Florin Coras3cbc04b2017-10-02 00:18:51 -07002056 vlib_node_increment_counter (vm, tcp4_node, evt, val);
Florin Coras6792ec02017-03-13 03:49:51 -07002057 else
Florin Coras3cbc04b2017-10-02 00:18:51 -07002058 vlib_node_increment_counter (vm, tcp6_node, evt, val);
Dave Barach68b0fb02017-02-28 15:15:56 -05002059}
2060
Florin Coras00cd22d2018-04-18 13:20:18 -07002061#define tcp_maybe_inc_counter(node_id, err, count) \
2062{ \
2063 if (next0 != tcp_next_drop (is_ip4)) \
2064 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2065 tcp6_##node_id##_node.index, is_ip4, err, \
2066 1); \
2067}
2068#define tcp_inc_counter(node_id, err, count) \
2069 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2070 tcp6_##node_id##_node.index, is_ip4, \
2071 err, count)
2072#define tcp_maybe_inc_err_counter(cnts, err) \
2073{ \
2074 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2075}
2076#define tcp_inc_err_counter(cnts, err, val) \
2077{ \
2078 cnts[err] += val; \
2079}
2080#define tcp_store_err_counters(node_id, cnts) \
2081{ \
2082 int i; \
2083 for (i = 0; i < TCP_N_ERROR; i++) \
2084 if (cnts[i]) \
2085 tcp_inc_counter(node_id, i, cnts[i]); \
2086}
2087
2088
Dave Barach68b0fb02017-02-28 15:15:56 -05002089always_inline uword
2090tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
Florin Coras4df38712018-06-20 12:44:16 -07002091 vlib_frame_t * frame, int is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05002092{
Florin Coras4df38712018-06-20 12:44:16 -07002093 u32 thread_index = vm->thread_index, errors = 0;
Florin Coras9ece3c02018-11-05 11:06:53 -08002094 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -08002095 u32 n_left_from, *from, *first_buffer;
Florin Coras00cd22d2018-04-18 13:20:18 -07002096 u16 err_counters[TCP_N_ERROR] = { 0 };
Dave Barach1f75cfd2017-04-14 16:46:44 -04002097 u8 is_fin = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002098
Florin Coras4df38712018-06-20 12:44:16 -07002099 if (node->flags & VLIB_NODE_FLAG_TRACE)
2100 tcp_established_trace_frame (vm, node, frame, is_ip4);
2101
Florin Coras7ac053b2018-11-05 15:57:21 -08002102 first_buffer = from = vlib_frame_vector_args (frame);
Florin Coras4df38712018-06-20 12:44:16 -07002103 n_left_from = frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002104
2105 while (n_left_from > 0)
2106 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002107 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2108 vlib_buffer_t *b0;
2109 tcp_header_t *th0 = 0;
2110 tcp_connection_t *tc0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002111
Florin Coras7ac053b2018-11-05 15:57:21 -08002112 if (n_left_from > 1)
Dave Barach68b0fb02017-02-28 15:15:56 -05002113 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002114 vlib_buffer_t *pb;
2115 pb = vlib_get_buffer (vm, from[1]);
2116 vlib_prefetch_buffer_header (pb, LOAD);
2117 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
Dave Barach68b0fb02017-02-28 15:15:56 -05002118 }
2119
Florin Coras7ac053b2018-11-05 15:57:21 -08002120 bi0 = from[0];
2121 from += 1;
2122 n_left_from -= 1;
2123
2124 b0 = vlib_get_buffer (vm, bi0);
2125 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2126 thread_index);
2127
2128 if (PREDICT_FALSE (tc0 == 0))
2129 {
2130 error0 = TCP_ERROR_INVALID_CONNECTION;
2131 goto done;
2132 }
2133
2134 th0 = tcp_buffer_hdr (b0);
2135 /* N.B. buffer is rewritten if segment is ooo. Thus, th0 becomes a
2136 * dangling reference. */
2137 is_fin = tcp_is_fin (th0);
2138
2139 /* SYNs, FINs and data consume sequence numbers */
2140 vnet_buffer (b0)->tcp.seq_end = vnet_buffer (b0)->tcp.seq_number
2141 + tcp_is_syn (th0) + is_fin + vnet_buffer (b0)->tcp.data_len;
2142
2143 /* TODO header prediction fast path */
2144
2145 /* 1-4: check SEQ, RST, SYN */
2146 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2147 {
2148 TCP_EVT_DBG (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2149 goto done;
2150 }
2151
2152 /* 5: check the ACK field */
2153 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2154 goto done;
2155
2156 /* 6: check the URG bit TODO */
2157
2158 /* 7: process the segment text */
2159 if (vnet_buffer (b0)->tcp.data_len)
2160 error0 = tcp_segment_rcv (wrk, tc0, b0);
2161
2162 /* 8: check the FIN bit */
2163 if (PREDICT_FALSE (is_fin))
Florin Corasb11175d2018-11-09 14:34:08 -08002164 tcp_rcv_fin (wrk, tc0, b0, &error0);
Florin Coras7ac053b2018-11-05 15:57:21 -08002165
2166 done:
2167 tcp_inc_err_counter (err_counters, error0, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -05002168 }
2169
Florin Coras3cbc04b2017-10-02 00:18:51 -07002170 errors = session_manager_flush_enqueue_events (TRANSPORT_PROTO_TCP,
Florin Coras4df38712018-06-20 12:44:16 -07002171 thread_index);
Florin Coras00cd22d2018-04-18 13:20:18 -07002172 err_counters[TCP_ERROR_EVENT_FIFO_FULL] = errors;
2173 tcp_store_err_counters (established, err_counters);
Florin Coras9ece3c02018-11-05 11:06:53 -08002174 tcp_handle_postponed_dequeues (wrk);
Florin Corasb11175d2018-11-09 14:34:08 -08002175 tcp_handle_disconnects (wrk);
Florin Coras7ac053b2018-11-05 15:57:21 -08002176 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
Florin Coras4df38712018-06-20 12:44:16 -07002177
2178 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002179}
2180
2181static uword
2182tcp4_established (vlib_main_t * vm, vlib_node_runtime_t * node,
2183 vlib_frame_t * from_frame)
2184{
2185 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2186}
2187
2188static uword
2189tcp6_established (vlib_main_t * vm, vlib_node_runtime_t * node,
2190 vlib_frame_t * from_frame)
2191{
2192 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2193}
2194
2195/* *INDENT-OFF* */
2196VLIB_REGISTER_NODE (tcp4_established_node) =
2197{
2198 .function = tcp4_established,
2199 .name = "tcp4-established",
2200 /* Takes a vector of packets. */
2201 .vector_size = sizeof (u32),
Florin Corase69f4952017-03-07 10:06:24 -08002202 .n_errors = TCP_N_ERROR,
2203 .error_strings = tcp_error_strings,
Dave Barach68b0fb02017-02-28 15:15:56 -05002204 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2205 .next_nodes =
2206 {
2207#define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2208 foreach_tcp_state_next
2209#undef _
2210 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002211 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002212};
2213/* *INDENT-ON* */
2214
2215VLIB_NODE_FUNCTION_MULTIARCH (tcp4_established_node, tcp4_established);
2216
2217/* *INDENT-OFF* */
2218VLIB_REGISTER_NODE (tcp6_established_node) =
2219{
2220 .function = tcp6_established,
2221 .name = "tcp6-established",
2222 /* Takes a vector of packets. */
2223 .vector_size = sizeof (u32),
2224 .n_errors = TCP_N_ERROR,
2225 .error_strings = tcp_error_strings,
2226 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2227 .next_nodes =
2228 {
2229#define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2230 foreach_tcp_state_next
2231#undef _
2232 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002233 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002234};
2235/* *INDENT-ON* */
2236
2237
2238VLIB_NODE_FUNCTION_MULTIARCH (tcp6_established_node, tcp6_established);
2239
2240vlib_node_registration_t tcp4_syn_sent_node;
2241vlib_node_registration_t tcp6_syn_sent_node;
2242
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002243static u8
2244tcp_lookup_is_valid (tcp_connection_t * tc, tcp_header_t * hdr)
2245{
Florin Corascea194d2017-10-02 00:18:51 -07002246 transport_connection_t *tmp = 0;
2247 u64 handle;
2248
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002249 if (!tc)
2250 return 1;
2251
Florin Coras70131132017-11-27 02:43:30 -08002252 /* Proxy case */
2253 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2254 return 1;
2255
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002256 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2257 && (tc->state == TCP_STATE_LISTEN
2258 || tc->c_rmt_port == hdr->src_port));
2259
2260 if (!is_valid)
2261 {
Florin Corascea194d2017-10-02 00:18:51 -07002262 handle = session_lookup_half_open_handle (&tc->connection);
2263 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
Florin Coras3cbc04b2017-10-02 00:18:51 -07002264 tc->c_proto, tc->c_is_ip4);
Florin Corascea194d2017-10-02 00:18:51 -07002265
2266 if (tmp)
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002267 {
2268 if (tmp->lcl_port == hdr->dst_port
2269 && tmp->rmt_port == hdr->src_port)
2270 {
Florin Corascea194d2017-10-02 00:18:51 -07002271 TCP_DBG ("half-open is valid!");
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002272 }
2273 }
2274 }
2275 return is_valid;
2276}
2277
2278/**
2279 * Lookup transport connection
2280 */
2281static tcp_connection_t *
Florin Corascea194d2017-10-02 00:18:51 -07002282tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2283 u8 is_ip4)
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002284{
2285 tcp_header_t *tcp;
2286 transport_connection_t *tconn;
2287 tcp_connection_t *tc;
Florin Corasdff48db2017-11-19 18:06:58 -08002288 u8 is_filtered = 0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002289 if (is_ip4)
2290 {
2291 ip4_header_t *ip4;
2292 ip4 = vlib_buffer_get_current (b);
2293 tcp = ip4_next_header (ip4);
Florin Corascea194d2017-10-02 00:18:51 -07002294 tconn = session_lookup_connection_wt4 (fib_index,
2295 &ip4->dst_address,
2296 &ip4->src_address,
2297 tcp->dst_port,
2298 tcp->src_port,
2299 TRANSPORT_PROTO_TCP,
Florin Corasdff48db2017-11-19 18:06:58 -08002300 thread_index, &is_filtered);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002301 tc = tcp_get_connection_from_transport (tconn);
2302 ASSERT (tcp_lookup_is_valid (tc, tcp));
2303 }
2304 else
2305 {
2306 ip6_header_t *ip6;
2307 ip6 = vlib_buffer_get_current (b);
2308 tcp = ip6_next_header (ip6);
Florin Corascea194d2017-10-02 00:18:51 -07002309 tconn = session_lookup_connection_wt6 (fib_index,
2310 &ip6->dst_address,
2311 &ip6->src_address,
2312 tcp->dst_port,
2313 tcp->src_port,
2314 TRANSPORT_PROTO_TCP,
Florin Corasdff48db2017-11-19 18:06:58 -08002315 thread_index, &is_filtered);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04002316 tc = tcp_get_connection_from_transport (tconn);
2317 ASSERT (tcp_lookup_is_valid (tc, tcp));
2318 }
2319 return tc;
2320}
2321
Dave Barach68b0fb02017-02-28 15:15:56 -05002322always_inline uword
2323tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2324 vlib_frame_t * from_frame, int is_ip4)
2325{
2326 tcp_main_t *tm = vnet_get_tcp_main ();
Florin Coras7ac053b2018-11-05 15:57:21 -08002327 u32 n_left_from, *from, *first_buffer, errors = 0;
2328 u32 my_thread_index = vm->thread_index;
2329 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
Dave Barach68b0fb02017-02-28 15:15:56 -05002330
Florin Coras7ac053b2018-11-05 15:57:21 -08002331 from = first_buffer = vlib_frame_vector_args (from_frame);
Dave Barach68b0fb02017-02-28 15:15:56 -05002332 n_left_from = from_frame->n_vectors;
2333
Dave Barach68b0fb02017-02-28 15:15:56 -05002334 while (n_left_from > 0)
2335 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002336 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2337 tcp_connection_t *tc0, *new_tc0;
2338 tcp_header_t *tcp0 = 0;
2339 tcp_rx_trace_t *t0;
2340 vlib_buffer_t *b0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002341
Florin Coras7ac053b2018-11-05 15:57:21 -08002342 bi0 = from[0];
2343 from += 1;
2344 n_left_from -= 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05002345
Florin Coras7ac053b2018-11-05 15:57:21 -08002346 b0 = vlib_get_buffer (vm, bi0);
2347 tc0 =
2348 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2349 if (PREDICT_FALSE (tc0 == 0))
Dave Barach68b0fb02017-02-28 15:15:56 -05002350 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002351 error0 = TCP_ERROR_INVALID_CONNECTION;
2352 goto drop;
Dave Barach68b0fb02017-02-28 15:15:56 -05002353 }
2354
Florin Coras7ac053b2018-11-05 15:57:21 -08002355 /* Half-open completed recently but the connection was't removed
2356 * yet by the owning thread */
2357 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2358 {
2359 /* Make sure the connection actually exists */
2360 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2361 my_thread_index, is_ip4));
2362 goto drop;
2363 }
2364
2365 ack0 = vnet_buffer (b0)->tcp.ack_number;
2366 seq0 = vnet_buffer (b0)->tcp.seq_number;
2367 tcp0 = tcp_buffer_hdr (b0);
2368
2369 /* Crude check to see if the connection handle does not match
2370 * the packet. Probably connection just switched to established */
2371 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2372 || tcp0->src_port != tc0->c_rmt_port))
2373 {
2374 error0 = TCP_ERROR_INVALID_CONNECTION;
2375 goto drop;
2376 }
2377
2378 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2379 && !tcp_syn (tcp0)))
2380 {
2381 error0 = TCP_ERROR_SEGMENT_INVALID;
2382 goto drop;
2383 }
2384
2385 /* SYNs, FINs and data consume sequence numbers */
2386 vnet_buffer (b0)->tcp.seq_end =
2387 seq0 + tcp_is_syn (tcp0) + tcp_is_fin (tcp0) +
2388 vnet_buffer (b0)->tcp.data_len;
2389
2390 /*
2391 * 1. check the ACK bit
2392 */
2393
2394 /*
2395 * If the ACK bit is set
2396 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2397 * the RST bit is set, if so drop the segment and return)
2398 * <SEQ=SEG.ACK><CTL=RST>
2399 * and discard the segment. Return.
2400 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2401 */
2402 if (tcp_ack (tcp0))
2403 {
2404 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2405 {
2406 if (!tcp_rst (tcp0))
2407 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
2408 error0 = TCP_ERROR_RCV_WND;
2409 goto drop;
2410 }
2411
2412 /* Make sure ACK is valid */
2413 if (seq_gt (tc0->snd_una, ack0))
2414 {
2415 error0 = TCP_ERROR_ACK_INVALID;
2416 goto drop;
2417 }
2418 }
2419
2420 /*
2421 * 2. check the RST bit
2422 */
2423
2424 if (tcp_rst (tcp0))
2425 {
2426 /* If ACK is acceptable, signal client that peer is not
2427 * willing to accept connection and drop connection*/
2428 if (tcp_ack (tcp0))
2429 tcp_connection_reset (tc0);
2430 error0 = TCP_ERROR_RST_RCVD;
2431 goto drop;
2432 }
2433
2434 /*
2435 * 3. check the security and precedence (skipped)
2436 */
2437
2438 /*
2439 * 4. check the SYN bit
2440 */
2441
2442 /* No SYN flag. Drop. */
2443 if (!tcp_syn (tcp0))
2444 {
2445 clib_warning ("not synack");
2446 error0 = TCP_ERROR_SEGMENT_INVALID;
2447 goto drop;
2448 }
2449
2450 /* Parse options */
Florin Coras80231112018-12-05 15:59:31 -08002451 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
Florin Coras7ac053b2018-11-05 15:57:21 -08002452 {
2453 clib_warning ("options parse fail");
2454 error0 = TCP_ERROR_OPTIONS;
2455 goto drop;
2456 }
2457
2458 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2459 * current thread pool. */
2460 pool_get (tm->connections[my_thread_index], new_tc0);
Dave Barach178cf492018-11-13 16:34:13 -05002461 clib_memcpy_fast (new_tc0, tc0, sizeof (*new_tc0));
Florin Coras7ac053b2018-11-05 15:57:21 -08002462 new_tc0->c_c_index = new_tc0 - tm->connections[my_thread_index];
2463 new_tc0->c_thread_index = my_thread_index;
2464 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2465 new_tc0->irs = seq0;
2466 new_tc0->timers[TCP_TIMER_ESTABLISH] = TCP_TIMER_HANDLE_INVALID;
2467 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2468 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2469
2470 /* If this is not the owning thread, wait for syn retransmit to
2471 * expire and cleanup then */
2472 if (tcp_half_open_connection_cleanup (tc0))
2473 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2474
2475 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2476 {
2477 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2478 new_tc0->tsval_recent_age = tcp_time_now ();
2479 }
2480
2481 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2482 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
Florin Corase80b5912018-12-12 19:25:43 -08002483 else
2484 new_tc0->rcv_wscale = 0;
Florin Coras7ac053b2018-11-05 15:57:21 -08002485
2486 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2487 << new_tc0->snd_wscale;
2488 new_tc0->snd_wl1 = seq0;
2489 new_tc0->snd_wl2 = ack0;
2490
2491 tcp_connection_init_vars (new_tc0);
2492
2493 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2494 if (PREDICT_TRUE (tcp_ack (tcp0)))
2495 {
2496 /* Our SYN is ACKed: we have iss < ack = snd_una */
2497
2498 /* TODO Dequeue acknowledged segments if we support Fast Open */
2499 new_tc0->snd_una = ack0;
2500 new_tc0->state = TCP_STATE_ESTABLISHED;
2501
2502 /* Make sure las is initialized for the wnd computation */
2503 new_tc0->rcv_las = new_tc0->rcv_nxt;
2504
2505 /* Notify app that we have connection. If session layer can't
2506 * allocate session send reset */
2507 if (session_stream_connect_notify (&new_tc0->connection, 0))
2508 {
2509 clib_warning ("connect notify fail");
2510 tcp_send_reset_w_pkt (new_tc0, b0, is_ip4);
2511 tcp_connection_cleanup (new_tc0);
2512 goto drop;
2513 }
2514
Florin Coras2e31cc32018-09-25 14:00:34 -07002515 new_tc0->tx_fifo_size =
2516 transport_tx_fifo_size (&new_tc0->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08002517 /* Update rtt with the syn-ack sample */
Florin Corasefefc6b2018-11-07 12:49:19 -08002518 tcp_estimate_initial_rtt (new_tc0);
Florin Coras7ac053b2018-11-05 15:57:21 -08002519 TCP_EVT_DBG (TCP_EVT_SYNACK_RCVD, new_tc0);
2520 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2521 }
2522 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2523 else
2524 {
2525 new_tc0->state = TCP_STATE_SYN_RCVD;
2526
2527 /* Notify app that we have connection */
2528 if (session_stream_connect_notify (&new_tc0->connection, 0))
2529 {
2530 tcp_connection_cleanup (new_tc0);
2531 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
2532 TCP_EVT_DBG (TCP_EVT_RST_SENT, tc0);
2533 goto drop;
2534 }
2535
Florin Coras2e31cc32018-09-25 14:00:34 -07002536 new_tc0->tx_fifo_size =
2537 transport_tx_fifo_size (&new_tc0->connection);
2538 new_tc0->rtt_ts = 0;
2539 tcp_init_snd_vars (new_tc0);
Florin Coras7ac053b2018-11-05 15:57:21 -08002540 tcp_send_synack (new_tc0);
2541 error0 = TCP_ERROR_SYNS_RCVD;
2542 goto drop;
2543 }
2544
2545 /* Read data, if any */
2546 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2547 {
2548 clib_warning ("rcvd data in syn-sent");
2549 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2550 if (error0 == TCP_ERROR_ACK_OK)
2551 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2552 }
2553 else
2554 {
2555 tcp_program_ack (wrk, new_tc0);
2556 }
2557
2558 drop:
2559
2560 tcp_inc_counter (syn_sent, error0, 1);
2561 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2562 {
2563 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
Dave Barach178cf492018-11-13 16:34:13 -05002564 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2565 clib_memcpy_fast (&t0->tcp_connection, tc0,
2566 sizeof (t0->tcp_connection));
Florin Coras7ac053b2018-11-05 15:57:21 -08002567 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002568 }
2569
Florin Coras3cbc04b2017-10-02 00:18:51 -07002570 errors = session_manager_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2571 my_thread_index);
Florin Coras00cd22d2018-04-18 13:20:18 -07002572 tcp_inc_counter (syn_sent, TCP_ERROR_EVENT_FIFO_FULL, errors);
Florin Coras7ac053b2018-11-05 15:57:21 -08002573 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2574
Dave Barach68b0fb02017-02-28 15:15:56 -05002575 return from_frame->n_vectors;
2576}
2577
2578static uword
2579tcp4_syn_sent (vlib_main_t * vm, vlib_node_runtime_t * node,
2580 vlib_frame_t * from_frame)
2581{
2582 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2583}
2584
2585static uword
2586tcp6_syn_sent_rcv (vlib_main_t * vm, vlib_node_runtime_t * node,
2587 vlib_frame_t * from_frame)
2588{
2589 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2590}
2591
2592/* *INDENT-OFF* */
2593VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2594{
2595 .function = tcp4_syn_sent,
2596 .name = "tcp4-syn-sent",
2597 /* Takes a vector of packets. */
2598 .vector_size = sizeof (u32),
2599 .n_errors = TCP_N_ERROR,
2600 .error_strings = tcp_error_strings,
2601 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2602 .next_nodes =
2603 {
2604#define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2605 foreach_tcp_state_next
2606#undef _
2607 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002608 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05002609};
2610/* *INDENT-ON* */
2611
2612VLIB_NODE_FUNCTION_MULTIARCH (tcp4_syn_sent_node, tcp4_syn_sent);
2613
2614/* *INDENT-OFF* */
2615VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2616{
2617 .function = tcp6_syn_sent_rcv,
2618 .name = "tcp6-syn-sent",
2619 /* Takes a vector of packets. */
2620 .vector_size = sizeof (u32),
2621 .n_errors = TCP_N_ERROR,
2622 .error_strings = tcp_error_strings,
2623 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2624 .next_nodes =
2625 {
2626#define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2627 foreach_tcp_state_next
2628#undef _
Clement Durand6cf260c2017-04-13 13:27:04 +02002629 },
2630 .format_trace = format_tcp_rx_trace_short,
2631};
Dave Barach68b0fb02017-02-28 15:15:56 -05002632/* *INDENT-ON* */
2633
2634VLIB_NODE_FUNCTION_MULTIARCH (tcp6_syn_sent_node, tcp6_syn_sent_rcv);
Florin Coras6534b7a2017-07-18 05:38:03 -04002635
Florin Coras3cbc04b2017-10-02 00:18:51 -07002636vlib_node_registration_t tcp4_rcv_process_node;
2637vlib_node_registration_t tcp6_rcv_process_node;
2638
Dave Barach68b0fb02017-02-28 15:15:56 -05002639/**
Florin Corasd79b41e2017-03-04 05:37:52 -08002640 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
Dave Barach68b0fb02017-02-28 15:15:56 -05002641 * as per RFC793 p. 64
2642 */
2643always_inline uword
2644tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2645 vlib_frame_t * from_frame, int is_ip4)
2646{
Florin Coras7ac053b2018-11-05 15:57:21 -08002647 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2648 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2649 u32 n_left_from, *from;
Dave Barach68b0fb02017-02-28 15:15:56 -05002650
Florin Coras7ac053b2018-11-05 15:57:21 -08002651 from = first_buffer = vlib_frame_vector_args (from_frame);
Dave Barach68b0fb02017-02-28 15:15:56 -05002652 n_left_from = from_frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002653
2654 while (n_left_from > 0)
2655 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002656 u32 bi0, error0 = TCP_ERROR_NONE;
2657 tcp_header_t *tcp0 = 0;
2658 tcp_connection_t *tc0;
2659 vlib_buffer_t *b0;
2660 u8 is_fin0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002661
Florin Coras7ac053b2018-11-05 15:57:21 -08002662 bi0 = from[0];
2663 from += 1;
2664 n_left_from -= 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05002665
Florin Coras7ac053b2018-11-05 15:57:21 -08002666 b0 = vlib_get_buffer (vm, bi0);
2667 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2668 thread_index);
2669 if (PREDICT_FALSE (tc0 == 0))
Dave Barach68b0fb02017-02-28 15:15:56 -05002670 {
Florin Coras7ac053b2018-11-05 15:57:21 -08002671 error0 = TCP_ERROR_INVALID_CONNECTION;
2672 goto drop;
Dave Barach68b0fb02017-02-28 15:15:56 -05002673 }
2674
Florin Coras7ac053b2018-11-05 15:57:21 -08002675 tcp0 = tcp_buffer_hdr (b0);
2676 is_fin0 = tcp_is_fin (tcp0);
2677
2678 /* SYNs, FINs and data consume sequence numbers */
2679 vnet_buffer (b0)->tcp.seq_end = vnet_buffer (b0)->tcp.seq_number
2680 + tcp_is_syn (tcp0) + is_fin0 + vnet_buffer (b0)->tcp.data_len;
2681
2682 if (CLIB_DEBUG)
2683 {
2684 tcp_connection_t *tmp;
2685 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2686 is_ip4);
2687 if (tmp->state != tc0->state)
2688 {
2689 clib_warning ("state changed");
2690 goto drop;
2691 }
2692 }
2693
2694 /*
2695 * Special treatment for CLOSED
2696 */
2697 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2698 {
2699 error0 = TCP_ERROR_CONNECTION_CLOSED;
2700 goto drop;
2701 }
2702
2703 /*
2704 * For all other states (except LISTEN)
2705 */
2706
2707 /* 1-4: check SEQ, RST, SYN */
2708 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2709 goto drop;
2710
2711 /* 5: check the ACK field */
2712 switch (tc0->state)
2713 {
2714 case TCP_STATE_SYN_RCVD:
2715 /*
2716 * If the segment acknowledgment is not acceptable, form a
2717 * reset segment,
2718 * <SEQ=SEG.ACK><CTL=RST>
2719 * and send it.
2720 */
2721 if (!tcp_rcv_ack_is_acceptable (tc0, b0))
2722 {
2723 TCP_DBG ("connection not accepted");
2724 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
2725 error0 = TCP_ERROR_ACK_INVALID;
2726 goto drop;
2727 }
2728
Florin Coras4850e3e2018-12-12 14:34:38 -08002729 /* Make sure the ack is exactly right */
Florin Coras2e7e6ae2018-12-12 23:31:33 -08002730 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
Florin Coras4850e3e2018-12-12 14:34:38 -08002731 {
2732 error0 = TCP_ERROR_SEGMENT_INVALID;
2733 tcp_send_reset_w_pkt (tc0, b0, is_ip4);
2734 goto drop;
2735 }
2736
Florin Coras7ac053b2018-11-05 15:57:21 -08002737 /* Update rtt and rto */
Florin Corasefefc6b2018-11-07 12:49:19 -08002738 tcp_estimate_initial_rtt (tc0);
Florin Coras7ac053b2018-11-05 15:57:21 -08002739
2740 /* Switch state to ESTABLISHED */
2741 tc0->state = TCP_STATE_ESTABLISHED;
2742 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2743
2744 /* Initialize session variables */
2745 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2746 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2747 << tc0->rcv_opts.wscale;
2748 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2749 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2750
2751 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2752 tcp_retransmit_timer_reset (tc0);
2753 tcp_timer_reset (tc0, TCP_TIMER_ESTABLISH);
2754 stream_session_accept_notify (&tc0->connection);
2755 error0 = TCP_ERROR_ACK_OK;
2756 break;
2757 case TCP_STATE_ESTABLISHED:
2758 /* We can get packets in established state here because they
2759 * were enqueued before state change */
2760 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2761 goto drop;
2762
2763 break;
2764 case TCP_STATE_FIN_WAIT_1:
2765 /* In addition to the processing for the ESTABLISHED state, if
2766 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2767 * continue processing in that state. */
2768 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2769 goto drop;
2770
2771 /* Still have to send the FIN */
2772 if (tc0->flags & TCP_CONN_FINPNDG)
2773 {
2774 /* TX fifo finally drained */
2775 if (!session_tx_fifo_max_dequeue (&tc0->connection))
2776 tcp_send_fin (tc0);
2777 }
2778 /* If FIN is ACKed */
2779 else if (tc0->snd_una == tc0->snd_una_max)
2780 {
2781 tc0->state = TCP_STATE_FIN_WAIT_2;
2782 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2783
2784 /* Stop all retransmit timers because we have nothing more
2785 * to send. Enable waitclose though because we're willing to
2786 * wait for peer's FIN but not indefinitely. */
2787 tcp_connection_timers_reset (tc0);
2788 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
Florin Corasefefc6b2018-11-07 12:49:19 -08002789
2790 /* Don't try to deq the FIN acked */
2791 if (tc0->burst_acked > 1)
2792 stream_session_dequeue_drop (&tc0->connection,
2793 tc0->burst_acked - 1);
2794 tc0->burst_acked = 0;
Florin Coras7ac053b2018-11-05 15:57:21 -08002795 }
2796 break;
2797 case TCP_STATE_FIN_WAIT_2:
2798 /* In addition to the processing for the ESTABLISHED state, if
2799 * the retransmission queue is empty, the user's CLOSE can be
2800 * acknowledged ("ok") but do not delete the TCB. */
2801 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2802 goto drop;
Florin Corasefefc6b2018-11-07 12:49:19 -08002803 tc0->burst_acked = 0;
Florin Coras7ac053b2018-11-05 15:57:21 -08002804 break;
2805 case TCP_STATE_CLOSE_WAIT:
2806 /* Do the same processing as for the ESTABLISHED state. */
2807 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2808 goto drop;
2809
2810 if (tc0->flags & TCP_CONN_FINPNDG)
2811 {
2812 /* TX fifo finally drained */
2813 if (!session_tx_fifo_max_dequeue (&tc0->connection))
2814 {
2815 tcp_send_fin (tc0);
2816 tcp_connection_timers_reset (tc0);
2817 tc0->state = TCP_STATE_LAST_ACK;
2818 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
2819 }
2820 }
2821 break;
2822 case TCP_STATE_CLOSING:
2823 /* In addition to the processing for the ESTABLISHED state, if
2824 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2825 * otherwise ignore the segment. */
2826 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2827 goto drop;
2828
2829 tc0->state = TCP_STATE_TIME_WAIT;
2830 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2831 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
2832 goto drop;
2833
2834 break;
2835 case TCP_STATE_LAST_ACK:
2836 /* The only thing that [should] arrive in this state is an
2837 * acknowledgment of our FIN. If our FIN is now acknowledged,
2838 * delete the TCB, enter the CLOSED state, and return. */
2839
2840 if (!tcp_rcv_ack_is_acceptable (tc0, b0))
2841 {
2842 error0 = TCP_ERROR_ACK_INVALID;
2843 goto drop;
2844 }
2845 error0 = TCP_ERROR_ACK_OK;
2846 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2847 /* Apparently our ACK for the peer's FIN was lost */
2848 if (is_fin0 && tc0->snd_una != tc0->snd_una_max)
2849 {
2850 tcp_send_fin (tc0);
2851 goto drop;
2852 }
2853
2854 tc0->state = TCP_STATE_CLOSED;
2855 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2856
2857 /* Don't free the connection from the data path since
2858 * we can't ensure that we have no packets already enqueued
2859 * to output. Rely instead on the waitclose timer */
2860 tcp_connection_timers_reset (tc0);
2861 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, 1);
2862
2863 goto drop;
2864
2865 break;
2866 case TCP_STATE_TIME_WAIT:
2867 /* The only thing that can arrive in this state is a
2868 * retransmission of the remote FIN. Acknowledge it, and restart
2869 * the 2 MSL timeout. */
2870
2871 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2872 goto drop;
2873
2874 tcp_program_ack (wrk, tc0);
2875 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
2876 goto drop;
2877
2878 break;
2879 default:
2880 ASSERT (0);
2881 }
2882
2883 /* 6: check the URG bit TODO */
2884
2885 /* 7: process the segment text */
2886 switch (tc0->state)
2887 {
2888 case TCP_STATE_ESTABLISHED:
2889 case TCP_STATE_FIN_WAIT_1:
2890 case TCP_STATE_FIN_WAIT_2:
2891 if (vnet_buffer (b0)->tcp.data_len)
2892 error0 = tcp_segment_rcv (wrk, tc0, b0);
2893 else if (is_fin0)
2894 tc0->rcv_nxt += 1;
2895 break;
2896 case TCP_STATE_CLOSE_WAIT:
2897 case TCP_STATE_CLOSING:
2898 case TCP_STATE_LAST_ACK:
2899 case TCP_STATE_TIME_WAIT:
2900 /* This should not occur, since a FIN has been received from the
2901 * remote side. Ignore the segment text. */
2902 break;
2903 }
2904
2905 /* 8: check the FIN bit */
2906 if (!is_fin0)
2907 goto drop;
2908
2909 switch (tc0->state)
2910 {
2911 case TCP_STATE_ESTABLISHED:
2912 case TCP_STATE_SYN_RCVD:
2913 /* Send FIN-ACK notify app and enter CLOSE-WAIT */
2914 tcp_connection_timers_reset (tc0);
2915 tcp_send_fin (tc0);
2916 stream_session_disconnect_notify (&tc0->connection);
2917 tc0->state = TCP_STATE_CLOSE_WAIT;
2918 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2919 break;
2920 case TCP_STATE_CLOSE_WAIT:
2921 case TCP_STATE_CLOSING:
2922 case TCP_STATE_LAST_ACK:
2923 /* move along .. */
2924 break;
2925 case TCP_STATE_FIN_WAIT_1:
2926 tc0->state = TCP_STATE_CLOSING;
2927 tcp_program_ack (wrk, tc0);
2928 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2929 /* Wait for ACK but not forever */
2930 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
2931 break;
2932 case TCP_STATE_FIN_WAIT_2:
2933 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2934 tc0->state = TCP_STATE_TIME_WAIT;
2935 tcp_connection_timers_reset (tc0);
2936 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
2937 tcp_program_ack (wrk, tc0);
2938 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc0);
2939 break;
2940 case TCP_STATE_TIME_WAIT:
2941 /* Remain in the TIME-WAIT state. Restart the time-wait
2942 * timeout.
2943 */
2944 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_TIMEWAIT_TIME);
2945 break;
2946 }
2947 error0 = TCP_ERROR_FIN_RCVD;
2948 TCP_EVT_DBG (TCP_EVT_FIN_RCVD, tc0);
2949
2950 drop:
2951
2952 tcp_inc_counter (rcv_process, error0, 1);
2953 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2954 {
2955 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2956 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2957 }
Dave Barach68b0fb02017-02-28 15:15:56 -05002958 }
2959
Florin Coras3cbc04b2017-10-02 00:18:51 -07002960 errors = session_manager_flush_enqueue_events (TRANSPORT_PROTO_TCP,
Florin Coras7ac053b2018-11-05 15:57:21 -08002961 thread_index);
Florin Coras00cd22d2018-04-18 13:20:18 -07002962 tcp_inc_counter (rcv_process, TCP_ERROR_EVENT_FIFO_FULL, errors);
Florin Coras9ece3c02018-11-05 11:06:53 -08002963 tcp_handle_postponed_dequeues (wrk);
Florin Coras7ac053b2018-11-05 15:57:21 -08002964 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2965
Dave Barach68b0fb02017-02-28 15:15:56 -05002966 return from_frame->n_vectors;
2967}
2968
2969static uword
2970tcp4_rcv_process (vlib_main_t * vm, vlib_node_runtime_t * node,
2971 vlib_frame_t * from_frame)
2972{
2973 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2974}
2975
2976static uword
2977tcp6_rcv_process (vlib_main_t * vm, vlib_node_runtime_t * node,
2978 vlib_frame_t * from_frame)
2979{
2980 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2981}
2982
2983/* *INDENT-OFF* */
2984VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2985{
2986 .function = tcp4_rcv_process,
2987 .name = "tcp4-rcv-process",
2988 /* Takes a vector of packets. */
2989 .vector_size = sizeof (u32),
2990 .n_errors = TCP_N_ERROR,
2991 .error_strings = tcp_error_strings,
2992 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2993 .next_nodes =
2994 {
2995#define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2996 foreach_tcp_state_next
2997#undef _
2998 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002999 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05003000};
3001/* *INDENT-ON* */
3002
3003VLIB_NODE_FUNCTION_MULTIARCH (tcp4_rcv_process_node, tcp4_rcv_process);
3004
3005/* *INDENT-OFF* */
3006VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3007{
3008 .function = tcp6_rcv_process,
3009 .name = "tcp6-rcv-process",
3010 /* Takes a vector of packets. */
3011 .vector_size = sizeof (u32),
3012 .n_errors = TCP_N_ERROR,
3013 .error_strings = tcp_error_strings,
3014 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3015 .next_nodes =
3016 {
3017#define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3018 foreach_tcp_state_next
3019#undef _
3020 },
Clement Durand6cf260c2017-04-13 13:27:04 +02003021 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05003022};
3023/* *INDENT-ON* */
3024
3025VLIB_NODE_FUNCTION_MULTIARCH (tcp6_rcv_process_node, tcp6_rcv_process);
3026
3027vlib_node_registration_t tcp4_listen_node;
3028vlib_node_registration_t tcp6_listen_node;
3029
3030/**
3031 * LISTEN state processing as per RFC 793 p. 65
3032 */
3033always_inline uword
3034tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3035 vlib_frame_t * from_frame, int is_ip4)
3036{
Florin Coras7ac053b2018-11-05 15:57:21 -08003037 u32 n_left_from, *from, n_syns = 0, *first_buffer;
Damjan Marion586afd72017-04-05 19:18:20 +02003038 u32 my_thread_index = vm->thread_index;
Dave Barach68b0fb02017-02-28 15:15:56 -05003039
Florin Coras7ac053b2018-11-05 15:57:21 -08003040 from = first_buffer = vlib_frame_vector_args (from_frame);
Dave Barach68b0fb02017-02-28 15:15:56 -05003041 n_left_from = from_frame->n_vectors;
3042
Dave Barach68b0fb02017-02-28 15:15:56 -05003043 while (n_left_from > 0)
3044 {
Florin Coras7ac053b2018-11-05 15:57:21 -08003045 u32 bi0;
3046 vlib_buffer_t *b0;
3047 tcp_rx_trace_t *t0;
3048 tcp_header_t *th0 = 0;
3049 tcp_connection_t *lc0;
3050 ip4_header_t *ip40;
3051 ip6_header_t *ip60;
3052 tcp_connection_t *child0;
3053 u32 error0 = TCP_ERROR_NONE;
Dave Barach68b0fb02017-02-28 15:15:56 -05003054
Florin Coras7ac053b2018-11-05 15:57:21 -08003055 bi0 = from[0];
3056 from += 1;
3057 n_left_from -= 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05003058
Florin Coras7ac053b2018-11-05 15:57:21 -08003059 b0 = vlib_get_buffer (vm, bi0);
3060 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3061
3062 if (is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05003063 {
Florin Coras7ac053b2018-11-05 15:57:21 -08003064 ip40 = vlib_buffer_get_current (b0);
3065 th0 = ip4_next_header (ip40);
3066 }
3067 else
3068 {
3069 ip60 = vlib_buffer_get_current (b0);
3070 th0 = ip6_next_header (ip60);
Dave Barach68b0fb02017-02-28 15:15:56 -05003071 }
3072
Florin Coras7ac053b2018-11-05 15:57:21 -08003073 /* Create child session. For syn-flood protection use filter */
3074
3075 /* 1. first check for an RST: handled in dispatch */
3076 /* if (tcp_rst (th0))
3077 goto drop;
3078 */
3079
3080 /* 2. second check for an ACK: handled in dispatch */
3081 /* if (tcp_ack (th0))
3082 {
3083 tcp_send_reset (b0, is_ip4);
3084 goto drop;
3085 }
3086 */
3087
3088 /* 3. check for a SYN (did that already) */
3089
3090 /* Make sure connection wasn't just created */
3091 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3092 is_ip4);
3093 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3094 {
3095 error0 = TCP_ERROR_CREATE_EXISTS;
3096 goto drop;
3097 }
3098
3099 /* Create child session and send SYN-ACK */
Florin Coras8124cb72018-12-16 20:57:29 -08003100 child0 = tcp_connection_alloc (my_thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -08003101 child0->c_lcl_port = th0->dst_port;
3102 child0->c_rmt_port = th0->src_port;
3103 child0->c_is_ip4 = is_ip4;
3104 child0->state = TCP_STATE_SYN_RCVD;
3105 child0->c_fib_index = lc0->c_fib_index;
3106
3107 if (is_ip4)
3108 {
3109 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3110 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3111 }
3112 else
3113 {
Dave Barach178cf492018-11-13 16:34:13 -05003114 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3115 sizeof (ip6_address_t));
3116 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3117 sizeof (ip6_address_t));
Florin Coras7ac053b2018-11-05 15:57:21 -08003118 }
3119
Florin Coras80231112018-12-05 15:59:31 -08003120 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
Florin Coras7ac053b2018-11-05 15:57:21 -08003121 {
Florin Coras8124cb72018-12-16 20:57:29 -08003122 error0 = TCP_ERROR_OPTIONS;
3123 tcp_connection_free (child0);
Florin Coras7ac053b2018-11-05 15:57:21 -08003124 goto drop;
3125 }
3126
3127 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3128 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3129 child0->rcv_las = child0->rcv_nxt;
3130 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3131
3132 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3133 * segments are used to initialize PAWS. */
3134 if (tcp_opts_tstamp (&child0->rcv_opts))
3135 {
3136 child0->tsval_recent = child0->rcv_opts.tsval;
3137 child0->tsval_recent_age = tcp_time_now ();
3138 }
3139
3140 if (tcp_opts_wscale (&child0->rcv_opts))
3141 child0->snd_wscale = child0->rcv_opts.wscale;
3142
3143 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3144 << child0->snd_wscale;
3145 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3146 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3147
3148 tcp_connection_init_vars (child0);
3149 TCP_EVT_DBG (TCP_EVT_SYN_RCVD, child0, 1);
3150
3151 if (stream_session_accept (&child0->connection, lc0->c_s_index,
3152 0 /* notify */ ))
3153 {
3154 clib_warning ("session accept fail");
3155 tcp_connection_cleanup (child0);
3156 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3157 goto drop;
3158 }
3159
Florin Coras2e31cc32018-09-25 14:00:34 -07003160 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
Florin Coras7ac053b2018-11-05 15:57:21 -08003161 tcp_send_synack (child0);
3162 tcp_timer_set (child0, TCP_TIMER_ESTABLISH, TCP_SYN_RCVD_TIME);
3163
3164 drop:
3165
3166 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3167 {
3168 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
Dave Barach178cf492018-11-13 16:34:13 -05003169 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3170 clib_memcpy_fast (&t0->tcp_connection, lc0,
3171 sizeof (t0->tcp_connection));
Florin Coras7ac053b2018-11-05 15:57:21 -08003172 }
3173
3174 n_syns += (error0 == TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003175 }
Florin Coras00cd22d2018-04-18 13:20:18 -07003176
3177 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
Florin Coras7ac053b2018-11-05 15:57:21 -08003178 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3179
Dave Barach68b0fb02017-02-28 15:15:56 -05003180 return from_frame->n_vectors;
3181}
3182
3183static uword
3184tcp4_listen (vlib_main_t * vm, vlib_node_runtime_t * node,
3185 vlib_frame_t * from_frame)
3186{
3187 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3188}
3189
3190static uword
3191tcp6_listen (vlib_main_t * vm, vlib_node_runtime_t * node,
3192 vlib_frame_t * from_frame)
3193{
3194 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3195}
3196
3197/* *INDENT-OFF* */
3198VLIB_REGISTER_NODE (tcp4_listen_node) =
3199{
3200 .function = tcp4_listen,
3201 .name = "tcp4-listen",
3202 /* Takes a vector of packets. */
3203 .vector_size = sizeof (u32),
3204 .n_errors = TCP_N_ERROR,
3205 .error_strings = tcp_error_strings,
3206 .n_next_nodes = TCP_LISTEN_N_NEXT,
3207 .next_nodes =
3208 {
3209#define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3210 foreach_tcp_state_next
3211#undef _
3212 },
Clement Durand6cf260c2017-04-13 13:27:04 +02003213 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05003214};
3215/* *INDENT-ON* */
3216
3217VLIB_NODE_FUNCTION_MULTIARCH (tcp4_listen_node, tcp4_listen);
3218
3219/* *INDENT-OFF* */
3220VLIB_REGISTER_NODE (tcp6_listen_node) =
3221{
3222 .function = tcp6_listen,
3223 .name = "tcp6-listen",
3224 /* Takes a vector of packets. */
3225 .vector_size = sizeof (u32),
3226 .n_errors = TCP_N_ERROR,
3227 .error_strings = tcp_error_strings,
3228 .n_next_nodes = TCP_LISTEN_N_NEXT,
3229 .next_nodes =
3230 {
3231#define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3232 foreach_tcp_state_next
3233#undef _
3234 },
Clement Durand6cf260c2017-04-13 13:27:04 +02003235 .format_trace = format_tcp_rx_trace_short,
Dave Barach68b0fb02017-02-28 15:15:56 -05003236};
3237/* *INDENT-ON* */
3238
3239VLIB_NODE_FUNCTION_MULTIARCH (tcp6_listen_node, tcp6_listen);
3240
3241vlib_node_registration_t tcp4_input_node;
3242vlib_node_registration_t tcp6_input_node;
3243
3244typedef enum _tcp_input_next
3245{
3246 TCP_INPUT_NEXT_DROP,
3247 TCP_INPUT_NEXT_LISTEN,
3248 TCP_INPUT_NEXT_RCV_PROCESS,
3249 TCP_INPUT_NEXT_SYN_SENT,
3250 TCP_INPUT_NEXT_ESTABLISHED,
3251 TCP_INPUT_NEXT_RESET,
Pierre Pfister7fe51f32017-09-20 08:48:36 +02003252 TCP_INPUT_NEXT_PUNT,
Dave Barach68b0fb02017-02-28 15:15:56 -05003253 TCP_INPUT_N_NEXT
3254} tcp_input_next_t;
3255
3256#define foreach_tcp4_input_next \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -08003257 _ (DROP, "ip4-drop") \
Dave Barach68b0fb02017-02-28 15:15:56 -05003258 _ (LISTEN, "tcp4-listen") \
3259 _ (RCV_PROCESS, "tcp4-rcv-process") \
3260 _ (SYN_SENT, "tcp4-syn-sent") \
3261 _ (ESTABLISHED, "tcp4-established") \
Pierre Pfister7fe51f32017-09-20 08:48:36 +02003262 _ (RESET, "tcp4-reset") \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -08003263 _ (PUNT, "ip4-punt")
Dave Barach68b0fb02017-02-28 15:15:56 -05003264
3265#define foreach_tcp6_input_next \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -08003266 _ (DROP, "ip6-drop") \
Dave Barach68b0fb02017-02-28 15:15:56 -05003267 _ (LISTEN, "tcp6-listen") \
3268 _ (RCV_PROCESS, "tcp6-rcv-process") \
3269 _ (SYN_SENT, "tcp6-syn-sent") \
3270 _ (ESTABLISHED, "tcp6-established") \
Pierre Pfister7fe51f32017-09-20 08:48:36 +02003271 _ (RESET, "tcp6-reset") \
Vijayabhaskar Katamreddyce074122017-11-15 13:50:26 -08003272 _ (PUNT, "ip6-punt")
Dave Barach68b0fb02017-02-28 15:15:56 -05003273
Dave Barach68b0fb02017-02-28 15:15:56 -05003274#define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3275
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003276static void
3277tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
Florin Coras4df38712018-06-20 12:44:16 -07003278 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -05003279{
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003280 tcp_connection_t *tc;
3281 tcp_header_t *tcp;
3282 tcp_rx_trace_t *t;
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003283 int i;
Dave Barach68b0fb02017-02-28 15:15:56 -05003284
Florin Coras4df38712018-06-20 12:44:16 -07003285 for (i = 0; i < n_bufs; i++)
Dave Barach68b0fb02017-02-28 15:15:56 -05003286 {
Florin Coras4df38712018-06-20 12:44:16 -07003287 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3288 {
3289 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3290 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3291 vm->thread_index);
3292 tcp = vlib_buffer_get_current (bs[i]);
3293 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3294 }
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003295 }
3296}
Dave Barach68b0fb02017-02-28 15:15:56 -05003297
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003298static void
3299tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3300{
3301 if (*error == TCP_ERROR_FILTERED)
3302 {
3303 *next = TCP_INPUT_NEXT_DROP;
3304 }
3305 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3306 {
3307 *next = TCP_INPUT_NEXT_PUNT;
3308 *error = TCP_ERROR_PUNT;
3309 }
3310 else
3311 {
3312 *next = TCP_INPUT_NEXT_RESET;
3313 *error = TCP_ERROR_NO_LISTENER;
3314 }
3315}
Dave Barach68b0fb02017-02-28 15:15:56 -05003316
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003317static inline tcp_connection_t *
3318tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3319 u8 is_ip4)
3320{
3321 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3322 int n_advance_bytes, n_data_bytes;
3323 transport_connection_t *tc;
3324 tcp_header_t *tcp;
3325 u8 is_filtered = 0;
3326
3327 if (is_ip4)
3328 {
3329 ip4_header_t *ip4 = vlib_buffer_get_current (b);
Florin Corasb8dda5f2018-12-05 10:03:34 -08003330 int ip_hdr_bytes = ip4_header_bytes (ip4);
3331 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3332 {
3333 *error = TCP_ERROR_LENGTH;
3334 return 0;
3335 }
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003336 tcp = ip4_next_header (ip4);
3337 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
Florin Corasb8dda5f2018-12-05 10:03:34 -08003338 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003339 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3340
3341 /* Length check. Checksum computed by ipx_local no need to compute again */
Florin Corasb8dda5f2018-12-05 10:03:34 -08003342 if (PREDICT_FALSE (n_data_bytes < 0))
Dave Barach68b0fb02017-02-28 15:15:56 -05003343 {
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003344 *error = TCP_ERROR_LENGTH;
3345 return 0;
Dave Barach68b0fb02017-02-28 15:15:56 -05003346 }
3347
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003348 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3349 &ip4->src_address, tcp->dst_port,
3350 tcp->src_port, TRANSPORT_PROTO_TCP,
3351 thread_index, &is_filtered);
3352 }
3353 else
3354 {
3355 ip6_header_t *ip6 = vlib_buffer_get_current (b);
Florin Corasb8dda5f2018-12-05 10:03:34 -08003356 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3357 {
3358 *error = TCP_ERROR_LENGTH;
3359 return 0;
3360 }
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003361 tcp = ip6_next_header (ip6);
3362 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3363 n_advance_bytes = tcp_header_bytes (tcp);
3364 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3365 - n_advance_bytes;
3366 n_advance_bytes += sizeof (ip6[0]);
3367
Florin Corasb8dda5f2018-12-05 10:03:34 -08003368 if (PREDICT_FALSE (n_data_bytes < 0))
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003369 {
3370 *error = TCP_ERROR_LENGTH;
3371 return 0;
3372 }
3373
3374 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3375 &ip6->src_address, tcp->dst_port,
3376 tcp->src_port, TRANSPORT_PROTO_TCP,
3377 thread_index, &is_filtered);
Dave Barach68b0fb02017-02-28 15:15:56 -05003378 }
3379
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003380 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3381 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3382 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3383 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3384 vnet_buffer (b)->tcp.flags = 0;
3385
3386 *error = is_filtered ? TCP_ERROR_FILTERED : *error;
3387
3388 return tcp_get_connection_from_transport (tc);
3389}
3390
3391static inline void
3392tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3393 vlib_buffer_t * b, u16 * next, u32 * error)
3394{
3395 tcp_header_t *tcp;
3396 u8 flags;
3397
3398 tcp = tcp_buffer_hdr (b);
3399 flags = tcp->flags & filter_flags;
3400 *next = tm->dispatch_table[tc->state][flags].next;
3401 *error = tm->dispatch_table[tc->state][flags].error;
3402
3403 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3404 || *next == TCP_INPUT_NEXT_RESET))
3405 {
3406 /* Overload tcp flags to store state */
3407 tcp_state_t state = tc->state;
3408 vnet_buffer (b)->tcp.flags = tc->state;
3409
3410 if (*error == TCP_ERROR_DISPATCH)
3411 clib_warning ("disp error state %U flags %U", format_tcp_state,
3412 state, format_tcp_flags, (int) flags);
3413 }
3414}
3415
3416always_inline uword
3417tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3418 vlib_frame_t * frame, int is_ip4)
3419{
3420 u32 n_left_from, *from, thread_index = vm->thread_index;
3421 tcp_main_t *tm = vnet_get_tcp_main ();
3422 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3423 u16 nexts[VLIB_FRAME_SIZE], *next;
3424
Florin Corasbe72ae62018-11-01 11:23:03 -07003425 tcp_set_time_now (tcp_get_worker (thread_index));
Florin Coras0c8a3bc2018-06-14 17:11:56 -07003426
3427 from = vlib_frame_vector_args (frame);
3428 n_left_from = frame->n_vectors;
3429 vlib_get_buffers (vm, from, bufs, n_left_from);
3430
3431 b = bufs;
3432 next = nexts;
3433
3434 while (n_left_from >= 4)
3435 {
3436 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3437 tcp_connection_t *tc0, *tc1;
3438
3439 {
3440 vlib_prefetch_buffer_header (b[2], STORE);
3441 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3442
3443 vlib_prefetch_buffer_header (b[3], STORE);
3444 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3445 }
3446
3447 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3448
3449 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4);
3450 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4);
3451
3452 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3453 {
3454 ASSERT (tcp_lookup_is_valid (tc0, tcp_buffer_hdr (b[0])));
3455 ASSERT (tcp_lookup_is_valid (tc1, tcp_buffer_hdr (b[1])));
3456
3457 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3458 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3459
3460 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3461 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3462 }
3463 else
3464 {
3465 if (PREDICT_TRUE (tc0 != 0))
3466 {
3467 ASSERT (tcp_lookup_is_valid (tc0, tcp_buffer_hdr (b[0])));
3468 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3469 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3470 }
3471 else
3472 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3473
3474 if (PREDICT_TRUE (tc1 != 0))
3475 {
3476 ASSERT (tcp_lookup_is_valid (tc1, tcp_buffer_hdr (b[1])));
3477 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3478 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3479 }
3480 else
3481 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3482 }
3483
3484 b += 2;
3485 next += 2;
3486 n_left_from -= 2;
3487 }
3488 while (n_left_from > 0)
3489 {
3490 tcp_connection_t *tc0;
3491 u32 error0 = TCP_ERROR_NO_LISTENER;
3492
3493 if (n_left_from > 1)
3494 {
3495 vlib_prefetch_buffer_header (b[1], STORE);
3496 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3497 }
3498
3499 next[0] = TCP_INPUT_NEXT_DROP;
3500 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4);
3501 if (PREDICT_TRUE (tc0 != 0))
3502 {
3503 ASSERT (tcp_lookup_is_valid (tc0, tcp_buffer_hdr (b[0])));
3504 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3505 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3506 }
3507 else
3508 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3509
3510 b += 1;
3511 next += 1;
3512 n_left_from -= 1;
3513 }
3514
3515 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3516 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3517
3518 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3519 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05003520}
3521
3522static uword
3523tcp4_input (vlib_main_t * vm, vlib_node_runtime_t * node,
3524 vlib_frame_t * from_frame)
3525{
3526 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3527}
3528
3529static uword
3530tcp6_input (vlib_main_t * vm, vlib_node_runtime_t * node,
3531 vlib_frame_t * from_frame)
3532{
3533 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3534}
3535
3536/* *INDENT-OFF* */
3537VLIB_REGISTER_NODE (tcp4_input_node) =
3538{
3539 .function = tcp4_input,
3540 .name = "tcp4-input",
3541 /* Takes a vector of packets. */
3542 .vector_size = sizeof (u32),
3543 .n_errors = TCP_N_ERROR,
3544 .error_strings = tcp_error_strings,
3545 .n_next_nodes = TCP_INPUT_N_NEXT,
3546 .next_nodes =
3547 {
3548#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3549 foreach_tcp4_input_next
3550#undef _
3551 },
3552 .format_buffer = format_tcp_header,
3553 .format_trace = format_tcp_rx_trace,
3554};
3555/* *INDENT-ON* */
3556
3557VLIB_NODE_FUNCTION_MULTIARCH (tcp4_input_node, tcp4_input);
3558
3559/* *INDENT-OFF* */
3560VLIB_REGISTER_NODE (tcp6_input_node) =
3561{
3562 .function = tcp6_input,
3563 .name = "tcp6-input",
3564 /* Takes a vector of packets. */
3565 .vector_size = sizeof (u32),
3566 .n_errors = TCP_N_ERROR,
3567 .error_strings = tcp_error_strings,
3568 .n_next_nodes = TCP_INPUT_N_NEXT,
3569 .next_nodes =
3570 {
3571#define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3572 foreach_tcp6_input_next
3573#undef _
3574 },
3575 .format_buffer = format_tcp_header,
3576 .format_trace = format_tcp_rx_trace,
3577};
3578/* *INDENT-ON* */
3579
3580VLIB_NODE_FUNCTION_MULTIARCH (tcp6_input_node, tcp6_input);
Dave Barach68b0fb02017-02-28 15:15:56 -05003581
3582static void
3583tcp_dispatch_table_init (tcp_main_t * tm)
3584{
3585 int i, j;
3586 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3587 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3588 {
3589 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3590 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3591 }
3592
3593#define _(t,f,n,e) \
3594do { \
3595 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3596 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3597} while (0)
3598
3599 /* SYNs for new connections -> tcp-listen. */
3600 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
Florin Corasdc629cd2017-05-09 00:52:37 -07003601 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
Florin Coras00cd22d2018-04-18 13:20:18 -07003602 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_RST_RCVD);
Dave Barach2c25a622017-06-26 11:35:07 -04003603 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3604 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003605 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3606 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasc28764f2017-04-26 00:08:42 -07003607 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corase8460c72018-09-24 14:40:40 -07003608 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3609 TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003610 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasc01c4452018-09-20 18:36:54 -07003611 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3612 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003613 /* SYN-ACK for a SYN */
3614 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3615 TCP_ERROR_NONE);
3616 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3617 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3618 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3619 TCP_ERROR_NONE);
3620 /* ACK for for established connection -> tcp-established. */
3621 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3622 /* FIN for for established connection -> tcp-established. */
3623 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3624 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3625 TCP_ERROR_NONE);
Florin Corasd79b41e2017-03-04 05:37:52 -08003626 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Corasdc629cd2017-05-09 00:52:37 -07003627 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3628 TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003629 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
Florin Coras3eb50622017-07-13 01:24:57 -04003630 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3631 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003632 /* ACK or FIN-ACK to our FIN */
3633 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3634 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3635 TCP_ERROR_NONE);
3636 /* FIN in reply to our FIN from the other side */
3637 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach2c25a622017-06-26 11:35:07 -04003638 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras56318932018-05-23 20:44:12 -07003639 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003640 /* FIN confirming that the peer (app) has closed */
3641 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasf6d68ed2017-05-07 19:12:02 -07003642 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003643 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3644 TCP_ERROR_NONE);
Florin Corasf03a59a2017-06-09 21:07:32 -07003645 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3646 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3647 TCP_ERROR_NONE);
Dave Barach68b0fb02017-02-28 15:15:56 -05003648 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras93992a92017-05-24 18:03:56 -07003649 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3650 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3651 TCP_ERROR_NONE);
Florin Corasdb84e572017-05-09 18:54:52 -07003652 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Corasc01d5782018-10-17 14:53:11 -07003653 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras93992a92017-05-24 18:03:56 -07003654 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3655 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3656 TCP_ERROR_NONE);
Florin Coras3eb50622017-07-13 01:24:57 -04003657 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras50958952017-08-29 14:50:13 -07003658 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
Florin Coras9d063042017-09-14 03:08:00 -04003659 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
Florin Corasdc629cd2017-05-09 00:52:37 -07003660 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
Florin Coras9d063042017-09-14 03:08:00 -04003661 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
Dave Barach2c25a622017-06-26 11:35:07 -04003662 TCP_ERROR_CONNECTION_CLOSED);
Dave Barach68b0fb02017-02-28 15:15:56 -05003663#undef _
3664}
3665
Florin Coras0dbd5172018-06-25 16:19:34 -07003666static clib_error_t *
Dave Barach68b0fb02017-02-28 15:15:56 -05003667tcp_input_init (vlib_main_t * vm)
3668{
3669 clib_error_t *error = 0;
3670 tcp_main_t *tm = vnet_get_tcp_main ();
3671
3672 if ((error = vlib_call_init_function (vm, tcp_init)))
3673 return error;
3674
3675 /* Initialize dispatch table. */
3676 tcp_dispatch_table_init (tm);
3677
3678 return error;
3679}
3680
3681VLIB_INIT_FUNCTION (tcp_input_init);
3682
3683/*
3684 * fd.io coding-style-patch-verification: ON
3685 *
3686 * Local Variables:
3687 * eval: (c-set-style "gnu")
3688 * End:
3689 */