blob: 928e8249eb1361214b2716fb7411ee0af4c1fb1a [file] [log] [blame]
Dave Barach68b0fb02017-02-28 15:15:56 -05001/*
Florin Coras222e1f412019-02-16 20:47:32 -08002 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
Dave Barach68b0fb02017-02-28 15:15:56 -05003 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16#include <vnet/tcp/tcp.h>
Florin Coras999840c2020-03-18 20:31:34 +000017#include <vnet/tcp/tcp_inlines.h>
Florin Corasb2215d62017-08-01 16:56:58 -070018#include <math.h>
Neale Rannse4031132020-10-26 13:00:06 +000019#include <vnet/ip/ip4_inlines.h>
20#include <vnet/ip/ip6_inlines.h>
Dave Barach68b0fb02017-02-28 15:15:56 -050021
Dave Barach2c25a622017-06-26 11:35:07 -040022typedef enum _tcp_output_next
Dave Barach68b0fb02017-02-28 15:15:56 -050023{
24 TCP_OUTPUT_NEXT_DROP,
Dave Barach2c25a622017-06-26 11:35:07 -040025 TCP_OUTPUT_NEXT_IP_LOOKUP,
Florin Corasf9d05682018-04-26 08:26:52 -070026 TCP_OUTPUT_NEXT_IP_REWRITE,
27 TCP_OUTPUT_NEXT_IP_ARP,
Dave Barach68b0fb02017-02-28 15:15:56 -050028 TCP_OUTPUT_N_NEXT
29} tcp_output_next_t;
30
31#define foreach_tcp4_output_next \
32 _ (DROP, "error-drop") \
Florin Corasf9d05682018-04-26 08:26:52 -070033 _ (IP_LOOKUP, "ip4-lookup") \
34 _ (IP_REWRITE, "ip4-rewrite") \
35 _ (IP_ARP, "ip4-arp")
Dave Barach68b0fb02017-02-28 15:15:56 -050036
37#define foreach_tcp6_output_next \
38 _ (DROP, "error-drop") \
Florin Corasf9d05682018-04-26 08:26:52 -070039 _ (IP_LOOKUP, "ip6-lookup") \
40 _ (IP_REWRITE, "ip6-rewrite") \
41 _ (IP_ARP, "ip6-discover-neighbor")
Dave Barach68b0fb02017-02-28 15:15:56 -050042
43static char *tcp_error_strings[] = {
44#define tcp_error(n,s) s,
45#include <vnet/tcp/tcp_error.def>
46#undef tcp_error
47};
48
49typedef struct
50{
Clement Durand6cf260c2017-04-13 13:27:04 +020051 tcp_header_t tcp_header;
52 tcp_connection_t tcp_connection;
Dave Barach68b0fb02017-02-28 15:15:56 -050053} tcp_tx_trace_t;
54
Filip Tehlare275bed2019-03-06 00:06:56 -080055static u8 *
Dave Barach68b0fb02017-02-28 15:15:56 -050056format_tcp_tx_trace (u8 * s, va_list * args)
57{
58 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
59 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
Clement Durand6cf260c2017-04-13 13:27:04 +020060 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
Florin Coras30928f82020-01-27 19:21:28 -080061 tcp_connection_t *tc = &t->tcp_connection;
Christophe Fontained3c008d2017-10-02 18:10:54 +020062 u32 indent = format_get_indent (s);
Dave Barach68b0fb02017-02-28 15:15:56 -050063
Florin Coras30928f82020-01-27 19:21:28 -080064 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
65 format_tcp_state, tc->state, format_white_space, indent,
66 format_tcp_header, &t->tcp_header, 128);
Dave Barach68b0fb02017-02-28 15:15:56 -050067
68 return s;
69}
70
Filip Tehlare275bed2019-03-06 00:06:56 -080071#ifndef CLIB_MARCH_VARIANT
Dave Barach68b0fb02017-02-28 15:15:56 -050072static u8
Florin Coras4eeeaaf2017-09-05 14:03:37 -040073tcp_window_compute_scale (u32 window)
Dave Barach68b0fb02017-02-28 15:15:56 -050074{
75 u8 wnd_scale = 0;
Florin Coras4eeeaaf2017-09-05 14:03:37 -040076 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
Dave Barach68b0fb02017-02-28 15:15:56 -050077 wnd_scale++;
78 return wnd_scale;
79}
80
81/**
Florin Coras6534b7a2017-07-18 05:38:03 -040082 * TCP's initial window
Florin Corase04c2992017-03-01 08:17:34 -080083 */
84always_inline u32
85tcp_initial_wnd_unscaled (tcp_connection_t * tc)
86{
Florin Coras6534b7a2017-07-18 05:38:03 -040087 /* RFC 6928 recommends the value lower. However at the time our connections
88 * are initialized, fifos may not be allocated. Therefore, advertise the
89 * smallest possible unscaled window size and update once fifos are
90 * assigned to the session.
91 */
92 /*
93 tcp_update_rcv_mss (tc);
94 TCP_IW_N_SEGMENTS * tc->mss;
95 */
Florin Coras9094b5c2019-08-12 14:17:47 -070096 return tcp_cfg.min_rx_fifo;
Florin Corase04c2992017-03-01 08:17:34 -080097}
98
99/**
Dave Barach68b0fb02017-02-28 15:15:56 -0500100 * Compute initial window and scale factor. As per RFC1323, window field in
101 * SYN and SYN-ACK segments is never scaled.
102 */
103u32
104tcp_initial_window_to_advertise (tcp_connection_t * tc)
105{
Florin Corase80b5912018-12-12 19:25:43 -0800106 /* Compute rcv wscale only if peer advertised support for it */
107 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
Florin Coras9094b5c2019-08-12 14:17:47 -0700108 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
Florin Corase80b5912018-12-12 19:25:43 -0800109
Florin Corase04c2992017-03-01 08:17:34 -0800110 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500111
112 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
113}
114
Florin Corasf20fd1a2019-03-28 13:21:19 -0700115static inline void
Florin Coras6792ec02017-03-13 03:49:51 -0700116tcp_update_rcv_wnd (tcp_connection_t * tc)
117{
Florin Corasf20fd1a2019-03-28 13:21:19 -0700118 u32 available_space, wnd;
Florin Coras6792ec02017-03-13 03:49:51 -0700119 i32 observed_wnd;
Florin Corasf20fd1a2019-03-28 13:21:19 -0700120
Florin Corase04c2992017-03-01 08:17:34 -0800121 /*
122 * Figure out how much space we have available
123 */
Florin Corasd2aab832018-05-22 11:39:59 -0700124 available_space = transport_max_rx_enqueue (&tc->connection);
Ryujiro Shibuyacc108562020-06-24 08:36:14 +0100125
Florin Corase04c2992017-03-01 08:17:34 -0800126 /*
127 * Use the above and what we know about what we've previously advertised
128 * to compute the new window
129 */
Florin Coras6792ec02017-03-13 03:49:51 -0700130 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
Florin Corase04c2992017-03-01 08:17:34 -0800131
Florin Corasc78d47b2020-07-06 08:06:54 -0700132 /* Check if we are about to retract the window. Do the comparison before
133 * rounding to avoid errors. Per RFC7323 sec. 2.4 we could remove this */
Florin Corasf20fd1a2019-03-28 13:21:19 -0700134 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
Florin Corase04c2992017-03-01 08:17:34 -0800135 {
Florin Corasc78d47b2020-07-06 08:06:54 -0700136 wnd = round_down_pow2 (clib_max (observed_wnd, 0), 1 << tc->rcv_wscale);
Florin Corasa436a422019-08-20 07:09:31 -0700137 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
Florin Corase04c2992017-03-01 08:17:34 -0800138 }
Florin Coras6792ec02017-03-13 03:49:51 -0700139 else
Florin Corase04c2992017-03-01 08:17:34 -0800140 {
Florin Corasc78d47b2020-07-06 08:06:54 -0700141 /* Make sure we have a multiple of 1 << rcv_wscale. We round down to
142 * avoid advertising a window larger than what can be buffered */
143 wnd = round_down_pow2 (available_space, 1 << tc->rcv_wscale);
Florin Corase04c2992017-03-01 08:17:34 -0800144 }
145
Florin Corasc78d47b2020-07-06 08:06:54 -0700146 if (PREDICT_FALSE (wnd < tc->rcv_opts.mss))
147 wnd = 0;
148
Florin Coras6792ec02017-03-13 03:49:51 -0700149 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
Dave Barach68b0fb02017-02-28 15:15:56 -0500150}
151
152/**
Florin Coras0dbd5172018-06-25 16:19:34 -0700153 * Compute and return window to advertise, scaled as per RFC1323
154 */
Florin Coras47596832019-03-12 18:58:54 -0700155static inline u32
Florin Coras0dbd5172018-06-25 16:19:34 -0700156tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
157{
158 if (state < TCP_STATE_ESTABLISHED)
159 return tcp_initial_window_to_advertise (tc);
160
161 tcp_update_rcv_wnd (tc);
Florin Coras0dbd5172018-06-25 16:19:34 -0700162 return tc->rcv_wnd >> tc->rcv_wscale;
163}
164
Florin Coras0dbd5172018-06-25 16:19:34 -0700165static int
Florin Corascedcf602019-08-27 12:15:43 -0700166tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
Dave Barach68b0fb02017-02-28 15:15:56 -0500167{
168 u8 len = 0;
169
170 opts->flags |= TCP_OPTS_FLAG_MSS;
Florin Corascedcf602019-08-27 12:15:43 -0700171 opts->mss = tc->mss;
Dave Barach68b0fb02017-02-28 15:15:56 -0500172 len += TCP_OPTION_LEN_MSS;
173
174 opts->flags |= TCP_OPTS_FLAG_WSCALE;
Florin Corascedcf602019-08-27 12:15:43 -0700175 opts->wscale = tc->rcv_wscale;
Dave Barach68b0fb02017-02-28 15:15:56 -0500176 len += TCP_OPTION_LEN_WINDOW_SCALE;
177
178 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
Florin Coras8f10b902021-04-02 18:32:00 -0700179 opts->tsval = tcp_time_tstamp (tc->c_thread_index);
Dave Barach68b0fb02017-02-28 15:15:56 -0500180 opts->tsecr = 0;
181 len += TCP_OPTION_LEN_TIMESTAMP;
182
Florin Coras93992a92017-05-24 18:03:56 -0700183 if (TCP_USE_SACKS)
184 {
185 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
186 len += TCP_OPTION_LEN_SACK_PERMITTED;
187 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500188
189 /* Align to needed boundary */
190 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
191 return len;
192}
193
Florin Coras0dbd5172018-06-25 16:19:34 -0700194static int
Dave Barach68b0fb02017-02-28 15:15:56 -0500195tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
196{
197 u8 len = 0;
198
199 opts->flags |= TCP_OPTS_FLAG_MSS;
Florin Corasc8343412017-05-04 14:25:50 -0700200 opts->mss = tc->mss;
Dave Barach68b0fb02017-02-28 15:15:56 -0500201 len += TCP_OPTION_LEN_MSS;
202
Florin Coras93992a92017-05-24 18:03:56 -0700203 if (tcp_opts_wscale (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500204 {
205 opts->flags |= TCP_OPTS_FLAG_WSCALE;
206 opts->wscale = tc->rcv_wscale;
207 len += TCP_OPTION_LEN_WINDOW_SCALE;
208 }
209
Florin Coras93992a92017-05-24 18:03:56 -0700210 if (tcp_opts_tstamp (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500211 {
212 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
Florin Coras8f10b902021-04-02 18:32:00 -0700213 opts->tsval = tcp_time_tstamp (tc->c_thread_index);
Dave Barach68b0fb02017-02-28 15:15:56 -0500214 opts->tsecr = tc->tsval_recent;
215 len += TCP_OPTION_LEN_TIMESTAMP;
216 }
217
Florin Coras93992a92017-05-24 18:03:56 -0700218 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500219 {
220 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
221 len += TCP_OPTION_LEN_SACK_PERMITTED;
222 }
223
224 /* Align to needed boundary */
225 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
226 return len;
227}
228
Florin Coras0dbd5172018-06-25 16:19:34 -0700229static int
Dave Barach68b0fb02017-02-28 15:15:56 -0500230tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
231{
232 u8 len = 0;
233
234 opts->flags = 0;
235
Florin Coras93992a92017-05-24 18:03:56 -0700236 if (tcp_opts_tstamp (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500237 {
238 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
Vladimir Kropylev1cfcb782019-07-02 11:25:26 +0300239 opts->tsval = tcp_tstamp (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500240 opts->tsecr = tc->tsval_recent;
241 len += TCP_OPTION_LEN_TIMESTAMP;
242 }
Florin Coras93992a92017-05-24 18:03:56 -0700243 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Dave Barach68b0fb02017-02-28 15:15:56 -0500244 {
245 if (vec_len (tc->snd_sacks))
246 {
247 opts->flags |= TCP_OPTS_FLAG_SACK;
Florin Corase5b17912019-02-21 16:46:24 -0800248 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
249 tc->snd_sack_pos = 0;
250 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
251 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
252 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
Florin Corasc28764f2017-04-26 00:08:42 -0700253 TCP_OPTS_MAX_SACK_BLOCKS);
Florin Corase5b17912019-02-21 16:46:24 -0800254 tc->snd_sack_pos += opts->n_sack_blocks;
Dave Barach68b0fb02017-02-28 15:15:56 -0500255 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
256 }
257 }
258
259 /* Align to needed boundary */
260 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
261 return len;
262}
263
264always_inline int
265tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
266 tcp_state_t state)
267{
268 switch (state)
269 {
270 case TCP_STATE_ESTABLISHED:
Florin Coras25579b42018-06-06 17:55:02 -0700271 case TCP_STATE_CLOSE_WAIT:
Florin Coras54ddf432018-12-21 13:54:09 -0800272 case TCP_STATE_FIN_WAIT_1:
273 case TCP_STATE_LAST_ACK:
274 case TCP_STATE_CLOSING:
275 case TCP_STATE_FIN_WAIT_2:
276 case TCP_STATE_TIME_WAIT:
277 case TCP_STATE_CLOSED:
Dave Barach68b0fb02017-02-28 15:15:56 -0500278 return tcp_make_established_options (tc, opts);
279 case TCP_STATE_SYN_RCVD:
280 return tcp_make_synack_options (tc, opts);
281 case TCP_STATE_SYN_SENT:
Florin Corascedcf602019-08-27 12:15:43 -0700282 return tcp_make_syn_options (tc, opts);
Dave Barach68b0fb02017-02-28 15:15:56 -0500283 default:
Florin Coras371ca502018-02-21 12:07:41 -0800284 clib_warning ("State not handled! %d", state);
Dave Barach68b0fb02017-02-28 15:15:56 -0500285 return 0;
286 }
287}
288
Florin Corasc8343412017-05-04 14:25:50 -0700289/**
Florin Corasb26743d2018-06-26 09:31:04 -0700290 * Update burst send vars
291 *
292 * - Updates snd_mss to reflect the effective segment size that we can send
293 * by taking into account all TCP options, including SACKs.
294 * - Cache 'on the wire' options for reuse
295 * - Updates receive window which can be reused for a burst.
296 *
297 * This should *only* be called when doing bursts
Florin Corasc8343412017-05-04 14:25:50 -0700298 */
299void
Florin Corasb26743d2018-06-26 09:31:04 -0700300tcp_update_burst_snd_vars (tcp_connection_t * tc)
Florin Corasc8343412017-05-04 14:25:50 -0700301{
Florin Corasb26743d2018-06-26 09:31:04 -0700302 tcp_main_t *tm = &tcp_main;
303
Florin Corasc8343412017-05-04 14:25:50 -0700304 /* Compute options to be used for connection. These may be reused when
305 * sending data or to compute the effective mss (snd_mss) */
Florin Corasb26743d2018-06-26 09:31:04 -0700306 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
307 TCP_STATE_ESTABLISHED);
Florin Corasc8343412017-05-04 14:25:50 -0700308
309 /* XXX check if MTU has been updated */
Florin Coras93992a92017-05-24 18:03:56 -0700310 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
Florin Corasdb84e572017-05-09 18:54:52 -0700311 ASSERT (tc->snd_mss > 0);
Florin Corasb26743d2018-06-26 09:31:04 -0700312
313 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
314 &tc->snd_opts);
315
316 tcp_update_rcv_wnd (tc);
Florin Coras52814732019-06-12 15:38:19 -0700317
Florin Corasbbcfaac2019-10-10 13:52:04 -0700318 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Corasd6ae4bf2019-10-12 18:10:20 -0700319 tcp_bt_check_app_limited (tc);
Florin Corasca2831a2019-07-04 17:05:59 -0700320
321 if (tc->snd_una == tc->snd_nxt)
Florin Corasc31dc312019-10-06 14:06:14 -0700322 {
323 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
Florin Coras11e9e352019-11-13 19:09:47 -0800324 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST);
Florin Corasc31dc312019-10-06 14:06:14 -0700325 }
Florin Corasfb9d3742020-11-05 19:01:44 -0800326
327 if (tc->flags & TCP_CONN_PSH_PENDING)
328 {
329 u32 max_deq = transport_max_tx_dequeue (&tc->connection);
330 /* Last byte marked for push */
331 tc->psh_seq = tc->snd_una + max_deq - 1;
332 }
Florin Corasc8343412017-05-04 14:25:50 -0700333}
334
Filip Tehlare275bed2019-03-06 00:06:56 -0800335#endif /* CLIB_MARCH_VARIANT */
Florin Corasc8343412017-05-04 14:25:50 -0700336
Florin Coras0dbd5172018-06-25 16:19:34 -0700337static void *
Dave Barach68b0fb02017-02-28 15:15:56 -0500338tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
339{
Florin Corasb2215d62017-08-01 16:56:58 -0700340 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
341 vlib_buffer_free_one (vm, b->next_buffer);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400342 /* Zero all flags but free list index and trace flag */
343 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
Florin Coras1f152cd2017-08-18 19:28:03 -0700344 b->current_data = 0;
345 b->current_length = 0;
346 b->total_length_not_including_first_buffer = 0;
347 vnet_buffer (b)->tcp.flags = 0;
Florin Corasb2215d62017-08-01 16:56:58 -0700348
Dave Barach68b0fb02017-02-28 15:15:56 -0500349 /* Leave enough space for headers */
Florin Coras1ee78302019-02-05 15:51:15 -0800350 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
Florin Coras1f152cd2017-08-18 19:28:03 -0700351}
352
Filip Tehlare275bed2019-03-06 00:06:56 -0800353#ifndef CLIB_MARCH_VARIANT
Florin Coras0dbd5172018-06-25 16:19:34 -0700354static void *
Florin Coras1f152cd2017-08-18 19:28:03 -0700355tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
356{
357 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400358 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
Florin Coras1f152cd2017-08-18 19:28:03 -0700359 b->total_length_not_including_first_buffer = 0;
Florin Coras24793e32018-05-09 11:34:25 -0700360 b->current_data = 0;
Florin Corasd79b41e2017-03-04 05:37:52 -0800361 vnet_buffer (b)->tcp.flags = 0;
Florin Corasf988e692017-11-27 04:34:14 -0500362 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
Florin Coras1f152cd2017-08-18 19:28:03 -0700363 /* Leave enough space for headers */
Florin Coras1ee78302019-02-05 15:51:15 -0800364 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
Dave Barach68b0fb02017-02-28 15:15:56 -0500365}
366
Srikanth A02833ff2019-10-02 17:48:58 -0700367
368/* Compute TCP checksum in software when offloading is disabled for a connection */
369u16
370ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
371 ip46_address_t * src, ip46_address_t * dst)
372{
373 ip_csum_t sum0;
374 u16 payload_length_host_byte_order;
375 u32 i;
376
377 /* Initialize checksum with ip header. */
378 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
379 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
380 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
381
382 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
383 {
384 sum0 = ip_csum_with_carry
385 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
386 sum0 = ip_csum_with_carry
387 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
388 }
389
390 return ip_calculate_l4_checksum (vm, p0, sum0,
391 payload_length_host_byte_order, NULL, 0,
392 NULL);
393}
394
395u16
396ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
397 ip46_address_t * src, ip46_address_t * dst)
398{
399 ip_csum_t sum0;
400 u32 payload_length_host_byte_order;
401
402 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
403 sum0 =
404 clib_host_to_net_u32 (payload_length_host_byte_order +
405 (IP_PROTOCOL_TCP << 16));
406
407 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
408 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
409
410 return ip_calculate_l4_checksum (vm, p0, sum0,
411 payload_length_host_byte_order, NULL, 0,
412 NULL);
413}
414
415static inline u16
416tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
417{
418 u16 checksum = 0;
Florin Corasbbcfaac2019-10-10 13:52:04 -0700419 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
Srikanth A02833ff2019-10-02 17:48:58 -0700420 {
421 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
422 vlib_main_t *vm = wrk->vm;
423
424 if (tc->c_is_ip4)
425 checksum = ip4_tcp_compute_checksum_custom
426 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
427 else
428 checksum = ip6_tcp_compute_checksum_custom
429 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
430 }
431 else
432 {
Mohsin Kazmi68095382021-02-10 11:26:24 +0100433 vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TCP_CKSUM);
Srikanth A02833ff2019-10-02 17:48:58 -0700434 }
435 return checksum;
436}
437
Dave Barach68b0fb02017-02-28 15:15:56 -0500438/**
439 * Prepare ACK
440 */
Florin Corasbdf7fd62019-01-31 17:31:01 -0800441static inline void
Dave Barach68b0fb02017-02-28 15:15:56 -0500442tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
443 u8 flags)
444{
445 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
446 u8 tcp_opts_len, tcp_hdr_opts_len;
447 tcp_header_t *th;
448 u16 wnd;
449
450 wnd = tcp_window_to_advertise (tc, state);
451
452 /* Make and write options */
453 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
454 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
455
456 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
457 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
458
459 tcp_options_write ((u8 *) (th + 1), snd_opts);
Srikanth A02833ff2019-10-02 17:48:58 -0700460
461 th->checksum = tcp_compute_checksum (tc, b);
462
Dave Barach68b0fb02017-02-28 15:15:56 -0500463 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Vladimir Kropylev398afbd2019-06-25 00:06:52 +0300464
465 if (wnd == 0)
466 tcp_zero_rwnd_sent_on (tc);
467 else
468 tcp_zero_rwnd_sent_off (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500469}
470
471/**
472 * Convert buffer to ACK
473 */
Florin Corasbdf7fd62019-01-31 17:31:01 -0800474static inline void
Dave Barach68b0fb02017-02-28 15:15:56 -0500475tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
476{
Dave Barach68b0fb02017-02-28 15:15:56 -0500477 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
Florin Corasa436a422019-08-20 07:09:31 -0700478 TCP_EVT (TCP_EVT_ACK_SENT, tc);
Florin Coras3e350af2017-03-30 02:54:28 -0700479 tc->rcv_las = tc->rcv_nxt;
Dave Barach68b0fb02017-02-28 15:15:56 -0500480}
481
482/**
483 * Convert buffer to FIN-ACK
484 */
Florin Coras999840c2020-03-18 20:31:34 +0000485static void
Florin Corasd79b41e2017-03-04 05:37:52 -0800486tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
Dave Barach68b0fb02017-02-28 15:15:56 -0500487{
Florin Corasbdf7fd62019-01-31 17:31:01 -0800488 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400489}
Dave Barach68b0fb02017-02-28 15:15:56 -0500490
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400491/**
492 * Convert buffer to SYN
493 */
494void
495tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
496{
497 u8 tcp_hdr_opts_len, tcp_opts_len;
498 tcp_header_t *th;
499 u16 initial_wnd;
500 tcp_options_t snd_opts;
501
502 initial_wnd = tcp_initial_window_to_advertise (tc);
503
504 /* Make and write options */
Dave Barachb7b92992018-10-17 10:38:51 -0400505 clib_memset (&snd_opts, 0, sizeof (snd_opts));
Florin Corascedcf602019-08-27 12:15:43 -0700506 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400507 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
508
509 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
510 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
511 initial_wnd);
512 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
513 tcp_options_write ((u8 *) (th + 1), &snd_opts);
Srikanth A02833ff2019-10-02 17:48:58 -0700514 th->checksum = tcp_compute_checksum (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500515}
516
517/**
518 * Convert buffer to SYN-ACK
519 */
Florin Coras999840c2020-03-18 20:31:34 +0000520static void
Dave Barach68b0fb02017-02-28 15:15:56 -0500521tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
522{
Dave Barach68b0fb02017-02-28 15:15:56 -0500523 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
524 u8 tcp_opts_len, tcp_hdr_opts_len;
525 tcp_header_t *th;
526 u16 initial_wnd;
Dave Barach68b0fb02017-02-28 15:15:56 -0500527
Dave Barachb7b92992018-10-17 10:38:51 -0400528 clib_memset (snd_opts, 0, sizeof (*snd_opts));
Dave Barach68b0fb02017-02-28 15:15:56 -0500529 initial_wnd = tcp_initial_window_to_advertise (tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500530 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
531 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
532
533 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
534 tc->rcv_nxt, tcp_hdr_opts_len,
535 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
Dave Barach68b0fb02017-02-28 15:15:56 -0500536 tcp_options_write ((u8 *) (th + 1), snd_opts);
537
538 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Srikanth A02833ff2019-10-02 17:48:58 -0700539 th->checksum = tcp_compute_checksum (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500540}
541
Florin Coras5484daa2020-03-27 23:55:06 +0000542static void
543tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
544 u8 is_ip4, u32 fib_index)
Dave Barach68b0fb02017-02-28 15:15:56 -0500545{
Florin Coras5484daa2020-03-27 23:55:06 +0000546 tcp_main_t *tm = &tcp_main;
Florin Corasbe72ae62018-11-01 11:23:03 -0700547 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -0500548
Damjan Marion213b5aa2017-07-13 21:19:27 +0200549 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
Dave Barach68b0fb02017-02-28 15:15:56 -0500550 b->error = 0;
551
Florin Coras56b39f62018-03-27 17:29:32 -0700552 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
553 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500554
Florin Corasf988e692017-11-27 04:34:14 -0500555 tcp_trajectory_add_start (b, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500556
Florin Coras5484daa2020-03-27 23:55:06 +0000557 session_add_pending_tx_buffer (vm->thread_index, bi,
558 tm->ipl_next_node[!is_ip4]);
Florin Coras9d063042017-09-14 03:08:00 -0400559
Florin Coras5484daa2020-03-27 23:55:06 +0000560 if (vm->thread_index == 0 && vlib_num_workers ())
561 session_queue_run_on_main_thread (wrk->vm);
Dave Barach68b0fb02017-02-28 15:15:56 -0500562}
563
Florin Coras0dbd5172018-06-25 16:19:34 -0700564static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700565tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
566 u8 is_ip4)
Florin Coras1f152cd2017-08-18 19:28:03 -0700567{
Florin Coras2a7ea2e2019-10-16 22:06:08 -0700568 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
569 b->error = 0;
570
Florin Coras5484daa2020-03-27 23:55:06 +0000571 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
572 wrk->tco_next_node[!is_ip4]);
Florin Coras1f152cd2017-08-18 19:28:03 -0700573}
574
Filip Tehlare275bed2019-03-06 00:06:56 -0800575#endif /* CLIB_MARCH_VARIANT */
Florin Coras1f152cd2017-08-18 19:28:03 -0700576
Florin Coras0dbd5172018-06-25 16:19:34 -0700577static int
Florin Coras360336f2020-02-13 18:46:18 +0000578tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b, u8 is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -0500579{
Dave Barach68b0fb02017-02-28 15:15:56 -0500580 ip4_header_t *ih4;
581 ip6_header_t *ih6;
Florin Coras360336f2020-02-13 18:46:18 +0000582 tcp_header_t *th;
583 ip4_address_t src_ip4, dst_ip4;
584 ip6_address_t src_ip6, dst_ip6;
Florin Corasdc629cd2017-05-09 00:52:37 -0700585 u16 src_port, dst_port;
Florin Coras360336f2020-02-13 18:46:18 +0000586 u32 tmp, len, seq, ack;
Florin Corasdc629cd2017-05-09 00:52:37 -0700587 u8 flags;
Dave Barach68b0fb02017-02-28 15:15:56 -0500588
589 /* Find IP and TCP headers */
Florin Coras360336f2020-02-13 18:46:18 +0000590 th = tcp_buffer_hdr (b);
Florin Corasdc629cd2017-05-09 00:52:37 -0700591
592 /* Save src and dst ip */
Dave Barach68b0fb02017-02-28 15:15:56 -0500593 if (is_ip4)
594 {
Florin Coras360336f2020-02-13 18:46:18 +0000595 ih4 = vlib_buffer_get_current (b);
Florin Corasdc629cd2017-05-09 00:52:37 -0700596 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
Florin Coras360336f2020-02-13 18:46:18 +0000597 src_ip4.as_u32 = ih4->src_address.as_u32;
598 dst_ip4.as_u32 = ih4->dst_address.as_u32;
Dave Barach68b0fb02017-02-28 15:15:56 -0500599 }
600 else
601 {
Florin Coras360336f2020-02-13 18:46:18 +0000602 ih6 = vlib_buffer_get_current (b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500603 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
Florin Coras360336f2020-02-13 18:46:18 +0000604 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
605 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
Dave Barach68b0fb02017-02-28 15:15:56 -0500606 }
607
Florin Coras360336f2020-02-13 18:46:18 +0000608 src_port = th->src_port;
609 dst_port = th->dst_port;
610 flags = TCP_FLAG_RST;
Florin Corasdc629cd2017-05-09 00:52:37 -0700611
Florin Coras360336f2020-02-13 18:46:18 +0000612 /*
613 * RFC 793. If the ACK bit is off, sequence number zero is used,
614 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
615 * If the ACK bit is on,
616 * <SEQ=SEG.ACK><CTL=RST>
617 */
618 if (tcp_ack (th))
Dave Barach68b0fb02017-02-28 15:15:56 -0500619 {
Florin Coras360336f2020-02-13 18:46:18 +0000620 seq = th->ack_number;
Florin Corasdc629cd2017-05-09 00:52:37 -0700621 ack = 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500622 }
Florin Coras360336f2020-02-13 18:46:18 +0000623 else
624 {
625 flags |= TCP_FLAG_ACK;
626 tmp = clib_net_to_host_u32 (th->seq_number);
627 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
628 ack = clib_host_to_net_u32 (tmp + len);
629 seq = 0;
630 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500631
Florin Coras360336f2020-02-13 18:46:18 +0000632 tcp_reuse_buffer (vm, b);
633 tcp_trajectory_add_start (b, 4);
634 th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack,
635 sizeof (tcp_header_t), flags, 0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500636
Dave Barach68b0fb02017-02-28 15:15:56 -0500637 if (is_ip4)
638 {
Florin Coras360336f2020-02-13 18:46:18 +0000639 ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4,
Florin Corasfdbc3822017-07-27 00:34:12 -0700640 IP_PROTOCOL_TCP, 1);
Florin Coras360336f2020-02-13 18:46:18 +0000641 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
Dave Barach68b0fb02017-02-28 15:15:56 -0500642 }
643 else
644 {
645 int bogus = ~0;
Florin Coras360336f2020-02-13 18:46:18 +0000646 ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP);
647 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
Dave Barach68b0fb02017-02-28 15:15:56 -0500648 ASSERT (!bogus);
649 }
650
651 return 0;
652}
653
Filip Tehlare275bed2019-03-06 00:06:56 -0800654#ifndef CLIB_MARCH_VARIANT
Dave Barach68b0fb02017-02-28 15:15:56 -0500655/**
656 * Send reset without reusing existing buffer
Florin Coras1f152cd2017-08-18 19:28:03 -0700657 *
658 * It extracts connection info out of original packet
Dave Barach68b0fb02017-02-28 15:15:56 -0500659 */
660void
Florin Corasd4c49be2019-02-07 00:15:53 -0800661tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
662 u32 thread_index, u8 is_ip4)
Dave Barach68b0fb02017-02-28 15:15:56 -0500663{
Florin Corasd4c49be2019-02-07 00:15:53 -0800664 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
Florin Corasbe72ae62018-11-01 11:23:03 -0700665 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -0500666 vlib_buffer_t *b;
Florin Coras56b39f62018-03-27 17:29:32 -0700667 u32 bi, sw_if_index, fib_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500668 u8 tcp_hdr_len, flags = 0;
669 tcp_header_t *th, *pkt_th;
670 u32 seq, ack;
671 ip4_header_t *ih4, *pkt_ih4;
672 ip6_header_t *ih6, *pkt_ih6;
Florin Coras56b39f62018-03-27 17:29:32 -0700673 fib_protocol_t fib_proto;
Dave Barach68b0fb02017-02-28 15:15:56 -0500674
Florin Corasbdf7fd62019-01-31 17:31:01 -0800675 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Corasd4712a82020-05-22 21:51:30 +0000676 {
677 tcp_worker_stats_inc (wrk, no_buffer, 1);
678 return;
679 }
Florin Coras66b11312017-07-31 17:18:03 -0700680
Dave Barach68b0fb02017-02-28 15:15:56 -0500681 b = vlib_get_buffer (vm, bi);
Florin Coras56b39f62018-03-27 17:29:32 -0700682 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
683 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
684 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
Florin Coras1f152cd2017-08-18 19:28:03 -0700685 tcp_init_buffer (vm, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500686
687 /* Make and write options */
688 tcp_hdr_len = sizeof (tcp_header_t);
689
690 if (is_ip4)
691 {
692 pkt_ih4 = vlib_buffer_get_current (pkt);
693 pkt_th = ip4_next_header (pkt_ih4);
694 }
695 else
696 {
697 pkt_ih6 = vlib_buffer_get_current (pkt);
698 pkt_th = ip6_next_header (pkt_ih6);
699 }
700
701 if (tcp_ack (pkt_th))
702 {
703 flags = TCP_FLAG_RST;
704 seq = pkt_th->ack_number;
Florin Coras776f3d82018-11-02 08:23:58 -0700705 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500706 }
707 else
708 {
709 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
710 seq = 0;
711 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
712 }
713
714 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
715 seq, ack, tcp_hdr_len, flags, 0);
716
717 /* Swap src and dst ip */
718 if (is_ip4)
719 {
720 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
721 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
Srikanth A02833ff2019-10-02 17:48:58 -0700722 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
Florin Corasbbcfaac2019-10-10 13:52:04 -0700723 tcp_csum_offload (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500724 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
725 }
726 else
727 {
728 int bogus = ~0;
Dave Barach68b0fb02017-02-28 15:15:56 -0500729 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
730 0x60);
Tarun Gupta2089c692019-11-04 16:35:59 -0800731 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
732 &pkt_ih6->src_address,
733 IP_PROTOCOL_TCP,
734 tc->ipv6_flow_label);
Dave Barach68b0fb02017-02-28 15:15:56 -0500735 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
736 ASSERT (!bogus);
737 }
738
Florin Coras5484daa2020-03-27 23:55:06 +0000739 tcp_enqueue_to_ip_lookup (wrk, b, bi, is_ip4, fib_index);
Florin Corasa436a422019-08-20 07:09:31 -0700740 TCP_EVT (TCP_EVT_RST_SENT, tc);
Florin Coras1f421012019-07-26 10:18:51 -0700741 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
742 TCP_ERROR_RST_SENT, 1);
Dave Barach68b0fb02017-02-28 15:15:56 -0500743}
744
Florin Coras1f152cd2017-08-18 19:28:03 -0700745/**
746 * Build and set reset packet for connection
747 */
748void
749tcp_send_reset (tcp_connection_t * tc)
750{
Florin Corasbe72ae62018-11-01 11:23:03 -0700751 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
752 vlib_main_t *vm = wrk->vm;
Florin Coras1f152cd2017-08-18 19:28:03 -0700753 vlib_buffer_t *b;
754 u32 bi;
755 tcp_header_t *th;
756 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
757 u8 flags;
758
Florin Corasbdf7fd62019-01-31 17:31:01 -0800759 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Corasd4712a82020-05-22 21:51:30 +0000760 {
761 tcp_worker_stats_inc (wrk, no_buffer, 1);
762 return;
763 }
Florin Coras1f152cd2017-08-18 19:28:03 -0700764 b = vlib_get_buffer (vm, bi);
765 tcp_init_buffer (vm, b);
766
767 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
768 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
Florin Coras4e783b92020-03-23 23:24:19 +0000769 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
Florin Coras1f152cd2017-08-18 19:28:03 -0700770 flags = TCP_FLAG_RST;
771 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
772 tc->rcv_nxt, tcp_hdr_opts_len, flags,
773 advertise_wnd);
774 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
Srikanth A02833ff2019-10-02 17:48:58 -0700775 th->checksum = tcp_compute_checksum (tc, b);
Florin Coras1f152cd2017-08-18 19:28:03 -0700776 ASSERT (opts_write_len == tc->snd_opts_len);
777 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Florin Corasdf36f492019-08-18 18:09:28 -0700778 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasa436a422019-08-20 07:09:31 -0700779 TCP_EVT (TCP_EVT_RST_SENT, tc);
Florin Coras1f421012019-07-26 10:18:51 -0700780 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
781 TCP_ERROR_RST_SENT, 1);
Florin Coras1f152cd2017-08-18 19:28:03 -0700782}
783
Florin Coras0dbd5172018-06-25 16:19:34 -0700784static void
Florin Corasbe72ae62018-11-01 11:23:03 -0700785tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
786 vlib_buffer_t * b)
Dave Barach68b0fb02017-02-28 15:15:56 -0500787{
Dave Barach68b0fb02017-02-28 15:15:56 -0500788 if (tc->c_is_ip4)
789 {
Florin Corasf4ce6ba2019-11-20 18:34:58 -0800790 vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4,
791 IP_PROTOCOL_TCP, tcp_csum_offload (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -0500792 }
793 else
794 {
Florin Corasf4ce6ba2019-11-20 18:34:58 -0800795 vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6,
796 IP_PROTOCOL_TCP, tc->ipv6_flow_label);
Dave Barach68b0fb02017-02-28 15:15:56 -0500797 }
798}
799
800/**
801 * Send SYN
802 *
803 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
804 * The packet is not forwarded through tcpx_output to avoid doing lookups
805 * in the half_open pool.
806 */
807void
808tcp_send_syn (tcp_connection_t * tc)
809{
Florin Corasbe72ae62018-11-01 11:23:03 -0700810 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
811 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -0500812 vlib_buffer_t *b;
813 u32 bi;
Dave Barach68b0fb02017-02-28 15:15:56 -0500814
Florin Corasf988e692017-11-27 04:34:14 -0500815 /*
816 * Setup retransmit and establish timers before requesting buffer
817 * such that we can return if we've ran out.
818 */
Florin Coras0765d972020-03-18 21:26:41 +0000819 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
Florin Corasf988e692017-11-27 04:34:14 -0500820 tc->rto * TCP_TO_TIMER_TICK);
821
Florin Corasbdf7fd62019-01-31 17:31:01 -0800822 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras222e1f412019-02-16 20:47:32 -0800823 {
Florin Coras0765d972020-03-18 21:26:41 +0000824 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
Florin Corasd4712a82020-05-22 21:51:30 +0000825 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Coras222e1f412019-02-16 20:47:32 -0800826 return;
827 }
Florin Coras66b11312017-07-31 17:18:03 -0700828
Dave Barach68b0fb02017-02-28 15:15:56 -0500829 b = vlib_get_buffer (vm, bi);
Florin Coras1f152cd2017-08-18 19:28:03 -0700830 tcp_init_buffer (vm, b);
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400831 tcp_make_syn (tc, b);
Dave Barach68b0fb02017-02-28 15:15:56 -0500832
833 /* Measure RTT with this */
Florin Corasefefc6b2018-11-07 12:49:19 -0800834 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
Dave Barach68b0fb02017-02-28 15:15:56 -0500835 tc->rtt_seq = tc->snd_nxt;
Dave Barach68b0fb02017-02-28 15:15:56 -0500836 tc->rto_boff = 0;
837
Florin Corasbe72ae62018-11-01 11:23:03 -0700838 tcp_push_ip_hdr (wrk, tc, b);
839 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
Florin Corasa436a422019-08-20 07:09:31 -0700840 TCP_EVT (TCP_EVT_SYN_SENT, tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500841}
842
Florin Coras7ac053b2018-11-05 15:57:21 -0800843void
844tcp_send_synack (tcp_connection_t * tc)
845{
846 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
847 vlib_main_t *vm = wrk->vm;
848 vlib_buffer_t *b;
849 u32 bi;
850
Florin Coraseaec00c2020-10-22 11:22:22 -0700851 ASSERT (tc->snd_una != tc->snd_nxt);
852 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
Florin Coras222e1f412019-02-16 20:47:32 -0800853
Florin Corasbdf7fd62019-01-31 17:31:01 -0800854 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras222e1f412019-02-16 20:47:32 -0800855 {
Florin Coras0765d972020-03-18 21:26:41 +0000856 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
Florin Corasd4712a82020-05-22 21:51:30 +0000857 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Coras222e1f412019-02-16 20:47:32 -0800858 return;
859 }
Florin Coras7ac053b2018-11-05 15:57:21 -0800860
Florin Corasdf084782018-12-06 17:41:10 -0800861 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
Florin Coras7ac053b2018-11-05 15:57:21 -0800862 b = vlib_get_buffer (vm, bi);
Florin Corasbdf7fd62019-01-31 17:31:01 -0800863 tcp_init_buffer (vm, b);
Florin Coras7ac053b2018-11-05 15:57:21 -0800864 tcp_make_synack (tc, b);
865 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasa436a422019-08-20 07:09:31 -0700866 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
Florin Coras7ac053b2018-11-05 15:57:21 -0800867}
868
Florin Coras66b11312017-07-31 17:18:03 -0700869/**
Dave Barach68b0fb02017-02-28 15:15:56 -0500870 * Send FIN
871 */
872void
873tcp_send_fin (tcp_connection_t * tc)
874{
Florin Corasbe72ae62018-11-01 11:23:03 -0700875 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
876 vlib_main_t *vm = wrk->vm;
Florin Coras9d063042017-09-14 03:08:00 -0400877 vlib_buffer_t *b;
878 u32 bi;
879 u8 fin_snt = 0;
880
Florin Corasc977e7c2018-10-16 20:30:31 -0700881 fin_snt = tc->flags & TCP_CONN_FINSNT;
882 if (fin_snt)
Florin Coras47596832019-03-12 18:58:54 -0700883 tc->snd_nxt -= 1;
Florin Corasc977e7c2018-10-16 20:30:31 -0700884
Florin Corasbdf7fd62019-01-31 17:31:01 -0800885 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coraseb97e5f2018-10-15 21:35:42 -0700886 {
887 /* Out of buffers so program fin retransmit ASAP */
Florin Coras0765d972020-03-18 21:26:41 +0000888 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
Florin Coras85a3ddd2018-12-24 16:54:34 -0800889 if (fin_snt)
Florin Coras47596832019-03-12 18:58:54 -0700890 tc->snd_nxt += 1;
Florin Coras222e1f412019-02-16 20:47:32 -0800891 else
892 /* Make sure retransmit retries a fin not data */
893 tc->flags |= TCP_CONN_FINSNT;
Florin Corasd4712a82020-05-22 21:51:30 +0000894 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Coras85a3ddd2018-12-24 16:54:34 -0800895 return;
Florin Coraseb97e5f2018-10-15 21:35:42 -0700896 }
897
Florin Corascb711a42019-10-16 19:28:17 -0700898 /* If we have non-dupacks programmed, no need to send them */
899 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
900 tc->flags &= ~TCP_CONN_SNDACK;
901
Dave Barach68b0fb02017-02-28 15:15:56 -0500902 b = vlib_get_buffer (vm, bi);
Florin Coras24793e32018-05-09 11:34:25 -0700903 tcp_init_buffer (vm, b);
Florin Corasd79b41e2017-03-04 05:37:52 -0800904 tcp_make_fin (tc, b);
Florin Coras2a7ea2e2019-10-16 22:06:08 -0700905 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasa436a422019-08-20 07:09:31 -0700906 TCP_EVT (TCP_EVT_FIN_SENT, tc);
Florin Coras47596832019-03-12 18:58:54 -0700907 /* Account for the FIN */
908 tc->snd_nxt += 1;
Florin Coraseaec00c2020-10-22 11:22:22 -0700909 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
Florin Coras9d063042017-09-14 03:08:00 -0400910 if (!fin_snt)
Florin Coras4eeeaaf2017-09-05 14:03:37 -0400911 {
912 tc->flags |= TCP_CONN_FINSNT;
913 tc->flags &= ~TCP_CONN_FINPNDG;
Florin Corasa096f2d2017-09-28 23:49:42 -0400914 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500915}
916
Dave Barach68b0fb02017-02-28 15:15:56 -0500917/**
Florin Corasfd247442019-03-12 16:56:26 -0700918 * Push TCP header and update connection variables. Should only be called
919 * for segments with data, not for 'control' packets.
Dave Barach68b0fb02017-02-28 15:15:56 -0500920 */
Florin Coras0dbd5172018-06-25 16:19:34 -0700921always_inline void
Florin Coras47596832019-03-12 18:58:54 -0700922tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
923 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
Dave Barach68b0fb02017-02-28 15:15:56 -0500924{
Florin Corasfd247442019-03-12 16:56:26 -0700925 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
Dave Barach68b0fb02017-02-28 15:15:56 -0500926 u32 advertise_wnd, data_len;
Florin Corasb26743d2018-06-26 09:31:04 -0700927 tcp_main_t *tm = &tcp_main;
Dave Barach68b0fb02017-02-28 15:15:56 -0500928 tcp_header_t *th;
929
Florin Corasb26743d2018-06-26 09:31:04 -0700930 data_len = b->current_length;
931 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
932 data_len += b->total_length_not_including_first_buffer;
933
Dave Barach68b0fb02017-02-28 15:15:56 -0500934 vnet_buffer (b)->tcp.flags = 0;
Florin Corasb26743d2018-06-26 09:31:04 -0700935 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
Dave Barach68b0fb02017-02-28 15:15:56 -0500936
Florin Corasc8343412017-05-04 14:25:50 -0700937 if (compute_opts)
938 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
939
Florin Corasc8343412017-05-04 14:25:50 -0700940 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
Florin Corasb26743d2018-06-26 09:31:04 -0700941
942 if (maybe_burst)
943 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
944 else
Florin Coras47596832019-03-12 18:58:54 -0700945 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
Florin Corasb26743d2018-06-26 09:31:04 -0700946
Florin Coras42ceddb2018-12-12 10:56:01 -0800947 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
948 {
Florin Coras47596832019-03-12 18:58:54 -0700949 if (seq_geq (tc->psh_seq, snd_nxt)
950 && seq_lt (tc->psh_seq, snd_nxt + data_len))
Florin Coras42ceddb2018-12-12 10:56:01 -0800951 flags |= TCP_FLAG_PSH;
952 }
Florin Coras47596832019-03-12 18:58:54 -0700953 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
Dave Barach68b0fb02017-02-28 15:15:56 -0500954 tc->rcv_nxt, tcp_hdr_opts_len, flags,
955 advertise_wnd);
Dave Barach68b0fb02017-02-28 15:15:56 -0500956
Florin Corasb26743d2018-06-26 09:31:04 -0700957 if (maybe_burst)
958 {
Dave Barach178cf492018-11-13 16:34:13 -0500959 clib_memcpy_fast ((u8 *) (th + 1),
960 tm->wrk_ctx[tc->c_thread_index].cached_opts,
961 tc->snd_opts_len);
Florin Corasb26743d2018-06-26 09:31:04 -0700962 }
963 else
964 {
965 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
966 ASSERT (len == tc->snd_opts_len);
967 }
Dave Barach68b0fb02017-02-28 15:15:56 -0500968
Florin Coras93992a92017-05-24 18:03:56 -0700969 /*
970 * Update connection variables
971 */
972
Florin Coras47596832019-03-12 18:58:54 -0700973 if (update_snd_nxt)
974 tc->snd_nxt += data_len;
Florin Corasc28764f2017-04-26 00:08:42 -0700975 tc->rcv_las = tc->rcv_nxt;
Florin Coras3e350af2017-03-30 02:54:28 -0700976
Florin Corasedfe0ee2019-07-29 18:13:25 -0700977 tc->bytes_out += data_len;
978 tc->data_segs_out += 1;
979
Srikanth A02833ff2019-10-02 17:48:58 -0700980 th->checksum = tcp_compute_checksum (tc, b);
981
Florin Corasa436a422019-08-20 07:09:31 -0700982 TCP_EVT (TCP_EVT_PKTIZE, tc);
Dave Barach68b0fb02017-02-28 15:15:56 -0500983}
984
Florin Corasd6ae4bf2019-10-12 18:10:20 -0700985always_inline u32
986tcp_buffer_len (vlib_buffer_t * b)
987{
988 u32 data_len = b->current_length;
989 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
990 data_len += b->total_length_not_including_first_buffer;
991 return data_len;
992}
993
Florin Coras0dbd5172018-06-25 16:19:34 -0700994u32
Florin Coras14ed6df2019-03-06 21:13:42 -0800995tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
Florin Coras0dbd5172018-06-25 16:19:34 -0700996{
Florin Coras14ed6df2019-03-06 21:13:42 -0800997 tcp_connection_t *tc = (tcp_connection_t *) tconn;
Florin Coras52814732019-06-12 15:38:19 -0700998
Florin Corasd6ae4bf2019-10-12 18:10:20 -0700999 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1000 tcp_bt_track_tx (tc, tcp_buffer_len (b));
Florin Coras52814732019-06-12 15:38:19 -07001001
Florin Coras47596832019-03-12 18:58:54 -07001002 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1003 /* update_snd_nxt */ 1);
Florin Coras52814732019-06-12 15:38:19 -07001004
Florin Coras55e556c2020-10-23 10:45:48 -07001005 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
Florin Coras0dbd5172018-06-25 16:19:34 -07001006 /* If not tracking an ACK, start tracking */
1007 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1008 {
Florin Corasd67f1122018-05-21 17:47:40 -07001009 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
Florin Coras0dbd5172018-06-25 16:19:34 -07001010 tc->rtt_seq = tc->snd_nxt;
1011 }
1012 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1013 {
Florin Coras0765d972020-03-18 21:26:41 +00001014 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1015 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
Florin Coras0dbd5172018-06-25 16:19:34 -07001016 tc->rto_boff = 0;
1017 }
1018 tcp_trajectory_add_start (b, 3);
1019 return 0;
1020}
1021
Dave Barach68b0fb02017-02-28 15:15:56 -05001022void
Florin Coras6792ec02017-03-13 03:49:51 -07001023tcp_send_ack (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001024{
Florin Corasbe72ae62018-11-01 11:23:03 -07001025 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1026 vlib_main_t *vm = wrk->vm;
Dave Barach68b0fb02017-02-28 15:15:56 -05001027 vlib_buffer_t *b;
1028 u32 bi;
1029
Florin Corasbdf7fd62019-01-31 17:31:01 -08001030 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras222e1f412019-02-16 20:47:32 -08001031 {
1032 tcp_update_rcv_wnd (tc);
Florin Corasd4712a82020-05-22 21:51:30 +00001033 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Coras222e1f412019-02-16 20:47:32 -08001034 return;
1035 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001036 b = vlib_get_buffer (vm, bi);
Florin Coras24793e32018-05-09 11:34:25 -07001037 tcp_init_buffer (vm, b);
Dave Barach68b0fb02017-02-28 15:15:56 -05001038 tcp_make_ack (tc, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001039 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05001040}
1041
Florin Coras7ac053b2018-11-05 15:57:21 -08001042void
Florin Coras26dd6de2019-07-23 23:54:47 -07001043tcp_program_ack (tcp_connection_t * tc)
Florin Coras7ac053b2018-11-05 15:57:21 -08001044{
1045 if (!(tc->flags & TCP_CONN_SNDACK))
1046 {
Florin Coras26dd6de2019-07-23 23:54:47 -07001047 session_add_self_custom_tx_evt (&tc->connection, 1);
Florin Coras7ac053b2018-11-05 15:57:21 -08001048 tc->flags |= TCP_CONN_SNDACK;
1049 }
1050}
1051
1052void
Florin Coras26dd6de2019-07-23 23:54:47 -07001053tcp_program_dupack (tcp_connection_t * tc)
Florin Coras7ac053b2018-11-05 15:57:21 -08001054{
1055 if (!(tc->flags & TCP_CONN_SNDACK))
1056 {
Florin Coras26dd6de2019-07-23 23:54:47 -07001057 session_add_self_custom_tx_evt (&tc->connection, 1);
Florin Coras7ac053b2018-11-05 15:57:21 -08001058 tc->flags |= TCP_CONN_SNDACK;
1059 }
1060 if (tc->pending_dupacks < 255)
1061 tc->pending_dupacks += 1;
1062}
1063
1064void
Florin Coras36ebcff2019-09-12 18:36:44 -07001065tcp_program_retransmit (tcp_connection_t * tc)
Florin Coras7ac053b2018-11-05 15:57:21 -08001066{
Florin Coras36ebcff2019-09-12 18:36:44 -07001067 if (!(tc->flags & TCP_CONN_RXT_PENDING))
Florin Coras7ac053b2018-11-05 15:57:21 -08001068 {
Florin Coras26dd6de2019-07-23 23:54:47 -07001069 session_add_self_custom_tx_evt (&tc->connection, 0);
Florin Coras36ebcff2019-09-12 18:36:44 -07001070 tc->flags |= TCP_CONN_RXT_PENDING;
Florin Coras7ac053b2018-11-05 15:57:21 -08001071 }
Florin Coras7ac053b2018-11-05 15:57:21 -08001072}
1073
Florin Corasb2215d62017-08-01 16:56:58 -07001074/**
Florin Coras017dc452019-08-30 11:06:35 -07001075 * Send window update ack
1076 *
1077 * Ensures that it will be sent only once, after a zero rwnd has been
1078 * advertised in a previous ack, and only if rwnd has grown beyond a
1079 * configurable value.
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001080 */
1081void
1082tcp_send_window_update_ack (tcp_connection_t * tc)
1083{
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001084 if (tcp_zero_rwnd_sent (tc))
1085 {
Florin Coras017dc452019-08-30 11:06:35 -07001086 tcp_update_rcv_wnd (tc);
1087 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001088 {
1089 tcp_zero_rwnd_sent_off (tc);
Florin Coras26dd6de2019-07-23 23:54:47 -07001090 tcp_program_ack (tc);
Vladimir Kropylev398afbd2019-06-25 00:06:52 +03001091 }
1092 }
1093}
1094
1095/**
Florin Coras36ee9f12018-11-02 12:52:10 -07001096 * Allocate a new buffer and build a new tcp segment
Dave Barach68b0fb02017-02-28 15:15:56 -05001097 *
Florin Coras36ee9f12018-11-02 12:52:10 -07001098 * @param wrk tcp worker
1099 * @param tc connection for which the segment will be allocated
1100 * @param offset offset of the first byte in the tx fifo
1101 * @param max_deq_byte segment size
1102 * @param[out] b pointer to buffer allocated
1103 *
1104 * @return the number of bytes in the segment or 0 if buffer cannot be
1105 * allocated or no data available
Florin Coras93992a92017-05-24 18:03:56 -07001106 */
Florin Coras36ee9f12018-11-02 12:52:10 -07001107static int
1108tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1109 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
Dave Barach68b0fb02017-02-28 15:15:56 -05001110{
Florin Corasbe72ae62018-11-01 11:23:03 -07001111 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1112 vlib_main_t *vm = wrk->vm;
Florin Corasbdf7fd62019-01-31 17:31:01 -08001113 u32 bi, seg_size;
Florin Coras93992a92017-05-24 18:03:56 -07001114 int n_bytes = 0;
Florin Corase87216f2017-08-17 16:59:22 -07001115 u8 *data;
Dave Barach68b0fb02017-02-28 15:15:56 -05001116
Florin Coras1ee78302019-02-05 15:51:15 -08001117 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
Florin Coras1f152cd2017-08-18 19:28:03 -07001118
Florin Corasb2215d62017-08-01 16:56:58 -07001119 /*
1120 * Prepare options
1121 */
Florin Corasc8343412017-05-04 14:25:50 -07001122 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1123
Florin Corasb2215d62017-08-01 16:56:58 -07001124 /*
1125 * Allocate and fill in buffer(s)
1126 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001127
Florin Corasb2215d62017-08-01 16:56:58 -07001128 /* Easy case, buffer size greater than mss */
Florin Corasbe72ae62018-11-01 11:23:03 -07001129 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
Florin Corasb2215d62017-08-01 16:56:58 -07001130 {
Florin Corasbdf7fd62019-01-31 17:31:01 -08001131 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Corasd4712a82020-05-22 21:51:30 +00001132 {
1133 tcp_worker_stats_inc (wrk, no_buffer, 1);
1134 return 0;
1135 }
Florin Coras24793e32018-05-09 11:34:25 -07001136 *b = vlib_get_buffer (vm, bi);
1137 data = tcp_init_buffer (vm, *b);
Florin Coras31c99552019-03-01 13:00:58 -08001138 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1139 max_deq_bytes);
Florin Corasb2215d62017-08-01 16:56:58 -07001140 ASSERT (n_bytes == max_deq_bytes);
1141 b[0]->current_length = n_bytes;
Florin Coras47596832019-03-12 18:58:54 -07001142 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1143 /* burst */ 0, /* update_snd_nxt */ 0);
Florin Corasb2215d62017-08-01 16:56:58 -07001144 }
1145 /* Split mss into multiple buffers */
1146 else
1147 {
Florin Corasbdf7fd62019-01-31 17:31:01 -08001148 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1149 u16 n_peeked, len_to_deq;
Florin Corasb2215d62017-08-01 16:56:58 -07001150 vlib_buffer_t *chain_b, *prev_b;
Florin Corasb2215d62017-08-01 16:56:58 -07001151 int i;
1152
Florin Corasb2215d62017-08-01 16:56:58 -07001153 /* Make sure we have enough buffers */
Florin Corasbe72ae62018-11-01 11:23:03 -07001154 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001155 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1156 CLIB_CACHE_LINE_BYTES);
1157 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1158 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
Florin Corasb2215d62017-08-01 16:56:58 -07001159 {
Florin Corasbdf7fd62019-01-31 17:31:01 -08001160 if (n_bufs)
1161 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
Florin Corasd4712a82020-05-22 21:51:30 +00001162 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001163 return 0;
Florin Corasb2215d62017-08-01 16:56:58 -07001164 }
1165
Florin Corasbdf7fd62019-01-31 17:31:01 -08001166 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
Florin Coras24793e32018-05-09 11:34:25 -07001167 data = tcp_init_buffer (vm, *b);
Florin Coras31c99552019-03-01 13:00:58 -08001168 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1169 bytes_per_buffer -
1170 TRANSPORT_MAX_HDRS_LEN);
Florin Corasb2215d62017-08-01 16:56:58 -07001171 b[0]->current_length = n_bytes;
1172 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1173 b[0]->total_length_not_including_first_buffer = 0;
Florin Corasb2215d62017-08-01 16:56:58 -07001174 max_deq_bytes -= n_bytes;
1175
1176 chain_b = *b;
1177 for (i = 1; i < n_bufs_per_seg; i++)
1178 {
1179 prev_b = chain_b;
Florin Corasbe72ae62018-11-01 11:23:03 -07001180 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001181 chain_bi = wrk->tx_buffers[--n_bufs];
Florin Corasb2215d62017-08-01 16:56:58 -07001182 chain_b = vlib_get_buffer (vm, chain_bi);
1183 chain_b->current_data = 0;
Florin Corase87216f2017-08-17 16:59:22 -07001184 data = vlib_buffer_get_current (chain_b);
Florin Coras31c99552019-03-01 13:00:58 -08001185 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1186 offset + n_bytes,
1187 len_to_deq);
Florin Corasb2215d62017-08-01 16:56:58 -07001188 ASSERT (n_peeked == len_to_deq);
Florin Coras1f152cd2017-08-18 19:28:03 -07001189 n_bytes += n_peeked;
Florin Corasb2215d62017-08-01 16:56:58 -07001190 chain_b->current_length = n_peeked;
Florin Coras1f152cd2017-08-18 19:28:03 -07001191 chain_b->next_buffer = 0;
Florin Corasb2215d62017-08-01 16:56:58 -07001192
1193 /* update previous buffer */
1194 prev_b->next_buffer = chain_bi;
1195 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1196
Florin Corasb2215d62017-08-01 16:56:58 -07001197 max_deq_bytes -= n_peeked;
Florin Coras1f152cd2017-08-18 19:28:03 -07001198 b[0]->total_length_not_including_first_buffer += n_peeked;
Florin Corasb2215d62017-08-01 16:56:58 -07001199 }
Florin Coras1f152cd2017-08-18 19:28:03 -07001200
Florin Coras47596832019-03-12 18:58:54 -07001201 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1202 /* burst */ 0, /* update_snd_nxt */ 0);
Florin Corasbdf7fd62019-01-31 17:31:01 -08001203
1204 if (PREDICT_FALSE (n_bufs))
1205 {
1206 clib_warning ("not all buffers consumed");
1207 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1208 }
Florin Corasb2215d62017-08-01 16:56:58 -07001209 }
1210
Florin Coras93992a92017-05-24 18:03:56 -07001211 ASSERT (n_bytes > 0);
Florin Corasbe72ae62018-11-01 11:23:03 -07001212 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
Florin Corasbb292f42017-05-19 09:49:19 -07001213
Florin Coras36ee9f12018-11-02 12:52:10 -07001214 return n_bytes;
1215}
1216
1217/**
1218 * Build a retransmit segment
1219 *
1220 * @return the number of bytes in the segment or 0 if there's nothing to
1221 * retransmit
1222 */
1223static u32
1224tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1225 tcp_connection_t * tc, u32 offset,
1226 u32 max_deq_bytes, vlib_buffer_t ** b)
1227{
1228 u32 start, available_bytes;
1229 int n_bytes = 0;
1230
1231 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1232 ASSERT (max_deq_bytes != 0);
1233
1234 /*
1235 * Make sure we can retransmit something
1236 */
Florin Coras31c99552019-03-01 13:00:58 -08001237 available_bytes = transport_max_tx_dequeue (&tc->connection);
Florin Coras36ee9f12018-11-02 12:52:10 -07001238 ASSERT (available_bytes >= offset);
1239 available_bytes -= offset;
1240 if (!available_bytes)
1241 return 0;
1242
1243 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1244 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1245
Florin Coras36ee9f12018-11-02 12:52:10 -07001246 start = tc->snd_una + offset;
Florin Coras81cb8e42019-10-22 19:44:45 -07001247 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1248
Florin Coras36ee9f12018-11-02 12:52:10 -07001249 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1250 if (!n_bytes)
1251 return 0;
1252
Florin Coras36ebcff2019-09-12 18:36:44 -07001253 tc->snd_rxt_bytes += n_bytes;
1254
Florin Corasbbcfaac2019-10-10 13:52:04 -07001255 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Coras36ebcff2019-09-12 18:36:44 -07001256 tcp_bt_track_rxt (tc, start, start + n_bytes);
Dave Barach68b0fb02017-02-28 15:15:56 -05001257
Florin Corasedfe0ee2019-07-29 18:13:25 -07001258 tc->bytes_retrans += n_bytes;
1259 tc->segs_retrans += 1;
Florin Coras0765d972020-03-18 21:26:41 +00001260 tcp_worker_stats_inc (wrk, rxt_segs, 1);
Florin Corasa436a422019-08-20 07:09:31 -07001261 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
Florin Coras36ebcff2019-09-12 18:36:44 -07001262
Dave Barach68b0fb02017-02-28 15:15:56 -05001263 return n_bytes;
1264}
1265
Florin Coras36ebcff2019-09-12 18:36:44 -07001266static void
1267tcp_check_sack_reneging (tcp_connection_t * tc)
1268{
1269 sack_scoreboard_t *sb = &tc->sack_sb;
1270 sack_scoreboard_hole_t *hole;
1271
1272 hole = scoreboard_first_hole (sb);
1273 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1274 return;
1275
1276 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1277}
1278
Florin Coras6792ec02017-03-13 03:49:51 -07001279/**
1280 * Reset congestion control, switch cwnd to loss window and try again.
1281 */
1282static void
Florin Corasa3c32652019-07-03 17:47:22 -07001283tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
Florin Coras6792ec02017-03-13 03:49:51 -07001284{
Florin Corasa436a422019-08-20 07:09:31 -07001285 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
Florin Coras36ebcff2019-09-12 18:36:44 -07001286
Florin Coras93992a92017-05-24 18:03:56 -07001287 tc->prev_ssthresh = tc->ssthresh;
1288 tc->prev_cwnd = tc->cwnd;
1289
Florin Coras36ebcff2019-09-12 18:36:44 -07001290 /* If we entrered loss without fast recovery, notify cc algo of the
1291 * congestion event such that it can update ssthresh and its state */
1292 if (!tcp_in_fastrecovery (tc))
1293 tcp_cc_congestion (tc);
Florin Corasa3c32652019-07-03 17:47:22 -07001294
Florin Coras36ebcff2019-09-12 18:36:44 -07001295 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
Florin Corasa3c32652019-07-03 17:47:22 -07001296 tcp_cc_loss (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001297
Florin Corasf1762d62017-09-24 19:43:08 -04001298 tc->rtt_ts = 0;
Florin Corasd2aab832018-05-22 11:39:59 -07001299 tc->cwnd_acc_bytes = 0;
Florin Corasedfe0ee2019-07-29 18:13:25 -07001300 tc->tr_occurences += 1;
Florin Corascc4d6d02020-07-29 23:03:39 -07001301 tc->sack_sb.reorder = TCP_DUPACK_THRESHOLD;
Florin Coras3af90fc2017-05-03 21:09:42 -07001302 tcp_recovery_on (tc);
Florin Coras6792ec02017-03-13 03:49:51 -07001303}
1304
Florin Coras75c48c12019-08-02 15:17:21 -07001305void
Florin Corasaa388692020-02-14 23:41:25 +00001306tcp_timer_retransmit_handler (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001307{
Florin Corasaa388692020-02-14 23:41:25 +00001308 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
Florin Corasbe72ae62018-11-01 11:23:03 -07001309 vlib_main_t *vm = wrk->vm;
Florin Corasb2215d62017-08-01 16:56:58 -07001310 vlib_buffer_t *b = 0;
Florin Coras3af90fc2017-05-03 21:09:42 -07001311 u32 bi, n_bytes;
Dave Barach68b0fb02017-02-28 15:15:56 -05001312
Florin Coras0765d972020-03-18 21:26:41 +00001313 tcp_worker_stats_inc (wrk, tr_events, 1);
Florin Coras75c48c12019-08-02 15:17:21 -07001314
Florin Corasaa388692020-02-14 23:41:25 +00001315 /* Should be handled by a different handler */
1316 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
Florin Coras75c48c12019-08-02 15:17:21 -07001317 return;
1318
Florin Coras75c48c12019-08-02 15:17:21 -07001319 /* Wait-close and retransmit could pop at the same time */
1320 if (tc->state == TCP_STATE_CLOSED)
1321 return;
Dave Barach68b0fb02017-02-28 15:15:56 -05001322
Florin Corase04c2992017-03-01 08:17:34 -08001323 if (tc->state >= TCP_STATE_ESTABLISHED)
Dave Barach68b0fb02017-02-28 15:15:56 -05001324 {
Florin Corasa436a422019-08-20 07:09:31 -07001325 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
Florin Corase55a6d72018-10-31 23:09:22 -07001326
Florin Coras93992a92017-05-24 18:03:56 -07001327 /* Lost FIN, retransmit and return */
Florin Coras222e1f412019-02-16 20:47:32 -08001328 if (tc->flags & TCP_CONN_FINSNT)
Florin Coras93992a92017-05-24 18:03:56 -07001329 {
1330 tcp_send_fin (tc);
Florin Corasf988e692017-11-27 04:34:14 -05001331 tc->rto_boff += 1;
1332 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
Florin Coras93992a92017-05-24 18:03:56 -07001333 return;
1334 }
1335
Florin Coraseaec00c2020-10-22 11:22:22 -07001336 /* Shouldn't be here */
1337 if (tc->snd_una == tc->snd_nxt)
Florin Corasa096f2d2017-09-28 23:49:42 -04001338 {
Florin Coras3ec66b02018-08-23 16:27:05 -07001339 ASSERT (!tcp_in_recovery (tc));
1340 tc->rto_boff = 0;
Florin Corasa096f2d2017-09-28 23:49:42 -04001341 return;
1342 }
1343
Florin Coras3ec66b02018-08-23 16:27:05 -07001344 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1345 * to persist timer timeout */
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001346 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1347 {
1348 tc->rto_boff = 0;
1349 tcp_update_rto (tc);
1350 }
1351
Florin Coras548f7572019-06-07 15:31:06 -07001352 /* Peer is dead or network connectivity is lost. Close connection.
1353 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1354 * a min rto of 0.2s we need to retry about 8 times. */
1355 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1356 {
1357 tcp_send_reset (tc);
1358 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1359 session_transport_closing_notify (&tc->connection);
Florin Coras52be6742019-11-14 23:32:08 -08001360 session_transport_closed_notify (&tc->connection);
Florin Coras548f7572019-06-07 15:31:06 -07001361 tcp_connection_timers_reset (tc);
Florin Coras7a3a8662020-02-22 02:27:21 +00001362 tcp_program_cleanup (wrk, tc);
Florin Coras0765d972020-03-18 21:26:41 +00001363 tcp_worker_stats_inc (wrk, tr_abort, 1);
Florin Coras548f7572019-06-07 15:31:06 -07001364 return;
1365 }
1366
Florin Coras36ebcff2019-09-12 18:36:44 -07001367 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1368 tcp_check_sack_reneging (tc);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001369
Florin Coras36ebcff2019-09-12 18:36:44 -07001370 /* Update send congestion to make sure that rxt has data to send */
1371 tc->snd_congestion = tc->snd_nxt;
Florin Corasa3c32652019-07-03 17:47:22 -07001372
Florin Coras36ebcff2019-09-12 18:36:44 -07001373 /* Send the first unacked segment. If we're short on buffers, return
1374 * as soon as possible */
Florin Coras81cb8e42019-10-22 19:44:45 -07001375 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1376 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
Florin Coras85a3ddd2018-12-24 16:54:34 -08001377 if (!n_bytes)
Florin Corase04c2992017-03-01 08:17:34 -08001378 {
Florin Coras0765d972020-03-18 21:26:41 +00001379 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
Florin Corase04c2992017-03-01 08:17:34 -08001380 return;
1381 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001382
Dave Barachb7f1faa2017-08-29 11:43:37 -04001383 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001384 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras75c48c12019-08-02 15:17:21 -07001385
1386 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
Florin Coraseaec00c2020-10-22 11:22:22 -07001387 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
Florin Coras36ebcff2019-09-12 18:36:44 -07001388
1389 tc->rto_boff += 1;
1390 if (tc->rto_boff == 1)
1391 {
1392 tcp_cc_init_rxt_timeout (tc);
1393 /* Record timestamp. Eifel detection algorithm RFC3522 */
1394 tc->snd_rxt_ts = tcp_tstamp (tc);
1395 }
1396
1397 if (tcp_opts_sack_permitted (&tc->rcv_opts))
Florin Corasbe237bf2019-09-27 08:16:40 -07001398 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
Florin Coras36ebcff2019-09-12 18:36:44 -07001399
1400 tcp_program_retransmit (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001401 }
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001402 /* Retransmit SYN-ACK */
1403 else if (tc->state == TCP_STATE_SYN_RCVD)
1404 {
Florin Corasa436a422019-08-20 07:09:31 -07001405 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
Florin Corase55a6d72018-10-31 23:09:22 -07001406
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001407 tc->rtt_ts = 0;
1408
Florin Coras75c48c12019-08-02 15:17:21 -07001409 /* Passive open establish timeout */
1410 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1411 {
1412 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1413 tcp_connection_timers_reset (tc);
Florin Coras7a3a8662020-02-22 02:27:21 +00001414 tcp_program_cleanup (wrk, tc);
Florin Coras0765d972020-03-18 21:26:41 +00001415 tcp_worker_stats_inc (wrk, tr_abort, 1);
Florin Coras75c48c12019-08-02 15:17:21 -07001416 return;
1417 }
Florin Coras222e1f412019-02-16 20:47:32 -08001418
Florin Corasbdf7fd62019-01-31 17:31:01 -08001419 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Corasf988e692017-11-27 04:34:14 -05001420 {
Florin Coras0765d972020-03-18 21:26:41 +00001421 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
Florin Corasd4712a82020-05-22 21:51:30 +00001422 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Corasf988e692017-11-27 04:34:14 -05001423 return;
1424 }
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001425
Florin Coras75c48c12019-08-02 15:17:21 -07001426 tc->rto_boff += 1;
1427 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1428 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1429
Florin Coraseaec00c2020-10-22 11:22:22 -07001430 ASSERT (tc->snd_una != tc->snd_nxt);
1431 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
Florin Coras75c48c12019-08-02 15:17:21 -07001432
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001433 b = vlib_get_buffer (vm, bi);
Florin Coras24793e32018-05-09 11:34:25 -07001434 tcp_init_buffer (vm, b);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001435 tcp_make_synack (tc, b);
Florin Corasa436a422019-08-20 07:09:31 -07001436 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
Florin Coras4eeeaaf2017-09-05 14:03:37 -04001437
1438 /* Retransmit timer already updated, just enqueue to output */
Florin Corasbe72ae62018-11-01 11:23:03 -07001439 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05001440 }
Florin Coras93992a92017-05-24 18:03:56 -07001441 else
1442 {
1443 ASSERT (tc->state == TCP_STATE_CLOSED);
Florin Coras93992a92017-05-24 18:03:56 -07001444 return;
1445 }
Dave Barach68b0fb02017-02-28 15:15:56 -05001446}
1447
Florin Coras75c48c12019-08-02 15:17:21 -07001448/**
1449 * SYN retransmit timer handler. Active open only.
1450 */
Dave Barach68b0fb02017-02-28 15:15:56 -05001451void
Florin Corasaa388692020-02-14 23:41:25 +00001452tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001453{
Florin Corasaa388692020-02-14 23:41:25 +00001454 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
Florin Coras75c48c12019-08-02 15:17:21 -07001455 vlib_main_t *vm = wrk->vm;
Florin Coras75c48c12019-08-02 15:17:21 -07001456 vlib_buffer_t *b = 0;
1457 u32 bi;
Dave Barach68b0fb02017-02-28 15:15:56 -05001458
Florin Coras75c48c12019-08-02 15:17:21 -07001459 /* Note: the connection may have transitioned to ESTABLISHED... */
Florin Corasaa388692020-02-14 23:41:25 +00001460 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
Florin Coras75c48c12019-08-02 15:17:21 -07001461 return;
1462
Florin Coras75c48c12019-08-02 15:17:21 -07001463 /* Half-open connection actually moved to established but we were
1464 * waiting for syn retransmit to pop to call cleanup from the right
1465 * thread. */
1466 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1467 {
1468 if (tcp_half_open_connection_cleanup (tc))
1469 TCP_DBG ("could not remove half-open connection");
1470 return;
1471 }
1472
Florin Corasa436a422019-08-20 07:09:31 -07001473 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
Florin Coras75c48c12019-08-02 15:17:21 -07001474 tc->rtt_ts = 0;
1475
1476 /* Active open establish timeout */
1477 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1478 {
Florin Coras00e01d32019-10-21 16:07:46 -07001479 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
Florin Coras75c48c12019-08-02 15:17:21 -07001480 tcp_connection_cleanup (tc);
1481 return;
1482 }
1483
1484 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1485 {
Florin Coras0765d972020-03-18 21:26:41 +00001486 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
Florin Corasd4712a82020-05-22 21:51:30 +00001487 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Coras75c48c12019-08-02 15:17:21 -07001488 return;
1489 }
1490
1491 /* Try without increasing RTO a number of times. If this fails,
1492 * start growing RTO exponentially */
1493 tc->rto_boff += 1;
1494 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1495 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1496
1497 b = vlib_get_buffer (vm, bi);
1498 tcp_init_buffer (vm, b);
1499 tcp_make_syn (tc, b);
1500
Florin Corasa436a422019-08-20 07:09:31 -07001501 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
Florin Coras75c48c12019-08-02 15:17:21 -07001502
1503 /* This goes straight to ipx_lookup */
1504 tcp_push_ip_hdr (wrk, tc, b);
1505 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1506
Florin Coras0765d972020-03-18 21:26:41 +00001507 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
Florin Coras75c48c12019-08-02 15:17:21 -07001508 tc->rto * TCP_TO_TIMER_TICK);
Dave Barach68b0fb02017-02-28 15:15:56 -05001509}
1510
1511/**
Florin Coras3e350af2017-03-30 02:54:28 -07001512 * Got 0 snd_wnd from peer, try to do something about it.
1513 *
1514 */
1515void
Florin Corasaa388692020-02-14 23:41:25 +00001516tcp_timer_persist_handler (tcp_connection_t * tc)
Florin Coras3e350af2017-03-30 02:54:28 -07001517{
Florin Corasaa388692020-02-14 23:41:25 +00001518 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
Florin Corasbe72ae62018-11-01 11:23:03 -07001519 u32 bi, max_snd_bytes, available_bytes, offset;
1520 tcp_main_t *tm = vnet_get_tcp_main ();
1521 vlib_main_t *vm = wrk->vm;
Florin Coras3e350af2017-03-30 02:54:28 -07001522 vlib_buffer_t *b;
Florin Coras93992a92017-05-24 18:03:56 -07001523 int n_bytes = 0;
Florin Coras1f152cd2017-08-18 19:28:03 -07001524 u8 *data;
Florin Coras3e350af2017-03-30 02:54:28 -07001525
Florin Coras3e350af2017-03-30 02:54:28 -07001526 /* Problem already solved or worse */
Florin Coras7e74bf32019-03-06 16:51:58 -08001527 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1528 || (tc->flags & TCP_CONN_FINSNT))
Florin Coras70f879d2020-03-13 17:54:42 +00001529 goto update_scheduler;
Florin Coras3e350af2017-03-30 02:54:28 -07001530
Florin Coras31c99552019-03-01 13:00:58 -08001531 available_bytes = transport_max_tx_dequeue (&tc->connection);
Florin Coras47596832019-03-12 18:58:54 -07001532 offset = tc->snd_nxt - tc->snd_una;
Florin Coras50958952017-08-29 14:50:13 -07001533
1534 /* Reprogram persist if no new bytes available to send. We may have data
1535 * next time */
1536 if (!available_bytes)
1537 {
Florin Coras0765d972020-03-18 21:26:41 +00001538 tcp_persist_timer_set (&wrk->timer_wheel, tc);
Florin Coras50958952017-08-29 14:50:13 -07001539 return;
1540 }
1541
1542 if (available_bytes <= offset)
Florin Coras70f879d2020-03-13 17:54:42 +00001543 goto update_scheduler;
Florin Coras50958952017-08-29 14:50:13 -07001544
Florin Coras3e350af2017-03-30 02:54:28 -07001545 /* Increment RTO backoff */
1546 tc->rto_boff += 1;
1547 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1548
Florin Corasb2215d62017-08-01 16:56:58 -07001549 /*
1550 * Try to force the first unsent segment (or buffer)
1551 */
Florin Corasbdf7fd62019-01-31 17:31:01 -08001552 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
Florin Coras3ec66b02018-08-23 16:27:05 -07001553 {
Florin Coras0765d972020-03-18 21:26:41 +00001554 tcp_persist_timer_set (&wrk->timer_wheel, tc);
Florin Corasd4712a82020-05-22 21:51:30 +00001555 tcp_worker_stats_inc (wrk, no_buffer, 1);
Florin Coras3ec66b02018-08-23 16:27:05 -07001556 return;
1557 }
Florin Coras70f879d2020-03-13 17:54:42 +00001558
Florin Coras3e350af2017-03-30 02:54:28 -07001559 b = vlib_get_buffer (vm, bi);
Florin Coras1f152cd2017-08-18 19:28:03 -07001560 data = tcp_init_buffer (vm, b);
Florin Coras93992a92017-05-24 18:03:56 -07001561
Florin Coras1f152cd2017-08-18 19:28:03 -07001562 tcp_validate_txf_size (tc, offset);
Florin Corasc8343412017-05-04 14:25:50 -07001563 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
Florin Coras7e74bf32019-03-06 16:51:58 -08001564 max_snd_bytes = clib_min (tc->snd_mss,
1565 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1566 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1567 max_snd_bytes);
Florin Coras3e350af2017-03-30 02:54:28 -07001568 b->current_length = n_bytes;
Florin Coras84275e92017-09-26 12:30:40 -04001569 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
Florin Coras55e556c2020-10-23 10:45:48 -07001570 || tc->snd_una == tc->snd_nxt
Florin Coras84275e92017-09-26 12:30:40 -04001571 || tc->rto_boff > 1));
Florin Coras93992a92017-05-24 18:03:56 -07001572
Florin Corasbbcfaac2019-10-10 13:52:04 -07001573 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
Florin Corasdd60b1b2019-10-07 17:19:09 -07001574 {
1575 tcp_bt_check_app_limited (tc);
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001576 tcp_bt_track_tx (tc, n_bytes);
Florin Corasdd60b1b2019-10-07 17:19:09 -07001577 }
1578
Florin Coras47596832019-03-12 18:58:54 -07001579 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1580 /* burst */ 0, /* update_snd_nxt */ 1);
Florin Coras55e556c2020-10-23 10:45:48 -07001581 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
Florin Corasbe72ae62018-11-01 11:23:03 -07001582 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras3e350af2017-03-30 02:54:28 -07001583
Florin Coras1f152cd2017-08-18 19:28:03 -07001584 /* Just sent new data, enable retransmit */
Florin Coras0765d972020-03-18 21:26:41 +00001585 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
Florin Coras70f879d2020-03-13 17:54:42 +00001586
Florin Coras6080e0d2020-03-13 20:39:43 +00001587 return;
1588
Florin Coras70f879d2020-03-13 17:54:42 +00001589update_scheduler:
1590
Florin Coras6080e0d2020-03-13 20:39:43 +00001591 if (tcp_is_descheduled (tc))
Florin Coras70f879d2020-03-13 17:54:42 +00001592 transport_connection_reschedule (&tc->connection);
Florin Coras3e350af2017-03-30 02:54:28 -07001593}
1594
1595/**
Florin Coras6792ec02017-03-13 03:49:51 -07001596 * Retransmit first unacked segment
1597 */
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001598int
Florin Corasbe72ae62018-11-01 11:23:03 -07001599tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
Dave Barach68b0fb02017-02-28 15:15:56 -05001600{
Florin Corasbe72ae62018-11-01 11:23:03 -07001601 vlib_main_t *vm = wrk->vm;
1602 vlib_buffer_t *b;
Florin Coras47596832019-03-12 18:58:54 -07001603 u32 bi, n_bytes;
Dave Barach68b0fb02017-02-28 15:15:56 -05001604
Florin Corasa436a422019-08-20 07:09:31 -07001605 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001606
Florin Corasbe72ae62018-11-01 11:23:03 -07001607 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
Florin Corasb2215d62017-08-01 16:56:58 -07001608 if (!n_bytes)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001609 return -1;
1610
Florin Corasb2215d62017-08-01 16:56:58 -07001611 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001612 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001613
1614 return 0;
Florin Coras6792ec02017-03-13 03:49:51 -07001615}
1616
Florin Coras36ee9f12018-11-02 12:52:10 -07001617static int
Florin Coras36ebcff2019-09-12 18:36:44 -07001618tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1619 u32 burst_size)
Florin Coras36ee9f12018-11-02 12:52:10 -07001620{
Florin Coras635acbf2019-07-31 14:11:05 -07001621 u32 offset, n_segs = 0, n_written, bi, available_wnd;
Florin Coras36ee9f12018-11-02 12:52:10 -07001622 vlib_main_t *vm = wrk->vm;
1623 vlib_buffer_t *b = 0;
1624
Florin Coras47596832019-03-12 18:58:54 -07001625 offset = tc->snd_nxt - tc->snd_una;
Florin Coras635acbf2019-07-31 14:11:05 -07001626 available_wnd = tc->snd_wnd - offset;
1627 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1628
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001629 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1630 tcp_bt_check_app_limited (tc);
1631
Florin Coras36ee9f12018-11-02 12:52:10 -07001632 while (n_segs < burst_size)
1633 {
1634 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1635 if (!n_written)
1636 goto done;
1637
1638 bi = vlib_get_buffer_index (vm, b);
1639 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1640 offset += n_written;
1641 n_segs += 1;
Florin Coras47596832019-03-12 18:58:54 -07001642
Florin Corasd6ae4bf2019-10-12 18:10:20 -07001643 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1644 tcp_bt_track_tx (tc, n_written);
1645
Florin Coras47596832019-03-12 18:58:54 -07001646 tc->snd_nxt += n_written;
Florin Coras36ee9f12018-11-02 12:52:10 -07001647 }
1648
1649done:
1650 return n_segs;
1651}
1652
Florin Coras36ebcff2019-09-12 18:36:44 -07001653/**
1654 * Estimate send space using proportional rate reduction (RFC6937)
1655 */
Florin Corasbe237bf2019-09-27 08:16:40 -07001656int
Florin Coras36ebcff2019-09-12 18:36:44 -07001657tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1658{
1659 u32 pipe, prr_out;
1660 int space;
1661
1662 pipe = tcp_flight_size (tc);
1663 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1664
1665 if (pipe > tc->ssthresh)
1666 {
1667 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1668 - prr_out;
1669 }
1670 else
1671 {
Florin Corasbe237bf2019-09-27 08:16:40 -07001672 int limit;
1673 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
Florin Coras36ebcff2019-09-12 18:36:44 -07001674 space = clib_min (tc->ssthresh - pipe, limit);
1675 }
1676 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1677 return space;
1678}
1679
Florin Corasbe237bf2019-09-27 08:16:40 -07001680static inline u8
1681tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1682 sack_scoreboard_t * sb)
1683{
1684 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1685 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1686
Florin Corasb3dce892019-10-30 09:22:14 -07001687 if (tcp_fastrecovery_first (tc))
1688 return 1;
1689
Florin Corasbe237bf2019-09-27 08:16:40 -07001690 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1691}
1692
Florin Corascb711a42019-10-16 19:28:17 -07001693static inline u8
1694tcp_max_tx_deq (tcp_connection_t * tc)
1695{
1696 return (transport_max_tx_dequeue (&tc->connection)
1697 - (tc->snd_nxt - tc->snd_una));
1698}
1699
Florin Coras36ee9f12018-11-02 12:52:10 -07001700#define scoreboard_rescue_rxt_valid(_sb, _tc) \
1701 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1702 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1703
Florin Coras6792ec02017-03-13 03:49:51 -07001704/**
Florin Coras36ebcff2019-09-12 18:36:44 -07001705 * Do retransmit with SACKs
Florin Coras6792ec02017-03-13 03:49:51 -07001706 */
Florin Coras36ebcff2019-09-12 18:36:44 -07001707static int
1708tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1709 u32 burst_size)
Dave Barach68b0fb02017-02-28 15:15:56 -05001710{
Florin Coras36ebcff2019-09-12 18:36:44 -07001711 u32 n_written = 0, offset, max_bytes, n_segs = 0;
Florin Coras11e9e352019-11-13 19:09:47 -08001712 u8 snd_limited = 0, can_rescue = 0;
1713 u32 bi, max_deq, burst_bytes;
Florin Coras93992a92017-05-24 18:03:56 -07001714 sack_scoreboard_hole_t *hole;
Florin Coras36ee9f12018-11-02 12:52:10 -07001715 vlib_main_t *vm = wrk->vm;
1716 vlib_buffer_t *b = 0;
Florin Coras93992a92017-05-24 18:03:56 -07001717 sack_scoreboard_t *sb;
Florin Coras93992a92017-05-24 18:03:56 -07001718 int snd_space;
Dave Barach68b0fb02017-02-28 15:15:56 -05001719
Florin Coras36ebcff2019-09-12 18:36:44 -07001720 ASSERT (tcp_in_cong_recovery (tc));
Dave Barach68b0fb02017-02-28 15:15:56 -05001721
Florin Corasa8e71c82019-10-22 19:01:39 -07001722 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
Florin Corasc31dc312019-10-06 14:06:14 -07001723 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1724 if (!burst_size)
1725 {
1726 tcp_program_retransmit (tc);
1727 return 0;
1728 }
1729
Florin Coras36ebcff2019-09-12 18:36:44 -07001730 if (tcp_in_recovery (tc))
1731 snd_space = tcp_available_cc_snd_space (tc);
1732 else
1733 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1734
Florin Corasca1c8f32018-05-23 21:01:30 -07001735 if (snd_space < tc->snd_mss)
Florin Coras11e9e352019-11-13 19:09:47 -08001736 goto done;
Florin Corasc31dc312019-10-06 14:06:14 -07001737
Florin Coras36ee9f12018-11-02 12:52:10 -07001738 sb = &tc->sack_sb;
Florin Corasbe237bf2019-09-27 08:16:40 -07001739
1740 /* Check if snd_una is a lost retransmit */
Florin Coras8a8b05c2019-10-16 10:07:39 -07001741 if (pool_elts (sb->holes)
1742 && seq_gt (sb->high_sacked, tc->snd_congestion)
Florin Corasbe237bf2019-09-27 08:16:40 -07001743 && tc->rxt_head != tc->snd_una
1744 && tcp_retransmit_should_retry_head (tc, sb))
1745 {
Florin Corasbf1f8b72019-11-04 14:39:33 -08001746 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1747 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
Florin Corasbe237bf2019-09-27 08:16:40 -07001748 if (!n_written)
1749 {
1750 tcp_program_retransmit (tc);
1751 goto done;
1752 }
1753 bi = vlib_get_buffer_index (vm, b);
1754 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1755 n_segs = 1;
1756
1757 tc->rxt_head = tc->snd_una;
1758 tc->rxt_delivered += n_written;
1759 tc->prr_delivered += n_written;
1760 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1761 }
1762
Florin Corasb3dce892019-10-30 09:22:14 -07001763 tcp_fastrecovery_first_off (tc);
1764
Florin Corasbe237bf2019-09-27 08:16:40 -07001765 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
Florin Coras36ee9f12018-11-02 12:52:10 -07001766 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1767
Florin Coras31c99552019-03-01 13:00:58 -08001768 max_deq = transport_max_tx_dequeue (&tc->connection);
Florin Coras47596832019-03-12 18:58:54 -07001769 max_deq -= tc->snd_nxt - tc->snd_una;
Florin Coras36ee9f12018-11-02 12:52:10 -07001770
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001771 while (snd_space > 0 && n_segs < burst_size)
Florin Coras93992a92017-05-24 18:03:56 -07001772 {
Florin Coras81cb8e42019-10-22 19:44:45 -07001773 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
Florin Coras36ee9f12018-11-02 12:52:10 -07001774 &snd_limited);
Florin Coras93992a92017-05-24 18:03:56 -07001775 if (!hole)
1776 {
Florin Coras36ebcff2019-09-12 18:36:44 -07001777 /* We are out of lost holes to retransmit so send some new data. */
Florin Corasbe237bf2019-09-27 08:16:40 -07001778 if (max_deq > tc->snd_mss)
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001779 {
Florin Corasc31dc312019-10-06 14:06:14 -07001780 u32 n_segs_new;
1781 int av_wnd;
1782
Florin Coras3eba7f12019-11-15 17:56:48 -08001783 /* Make sure we don't exceed available window and leave space
1784 * for one more packet, to avoid zero window acks */
Florin Corasc31dc312019-10-06 14:06:14 -07001785 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
Florin Coras3eba7f12019-11-15 17:56:48 -08001786 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
Florin Corasc31dc312019-10-06 14:06:14 -07001787 snd_space = clib_min (snd_space, av_wnd);
Florin Coras36ee9f12018-11-02 12:52:10 -07001788 snd_space = clib_min (max_deq, snd_space);
1789 burst_size = clib_min (burst_size - n_segs,
1790 snd_space / tc->snd_mss);
Florin Coras36ebcff2019-09-12 18:36:44 -07001791 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1792 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1793 if (max_deq > n_segs_new * tc->snd_mss)
1794 tcp_program_retransmit (tc);
1795
1796 n_segs += n_segs_new;
Florin Coras36ee9f12018-11-02 12:52:10 -07001797 goto done;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001798 }
Florin Coras93992a92017-05-24 18:03:56 -07001799
Florin Coras36ebcff2019-09-12 18:36:44 -07001800 if (tcp_in_recovery (tc) || !can_rescue
1801 || scoreboard_rescue_rxt_valid (sb, tc))
Florin Coras36ee9f12018-11-02 12:52:10 -07001802 break;
1803
Florin Coras93992a92017-05-24 18:03:56 -07001804 /* If rescue rxt undefined or less than snd_una then one segment of
1805 * up to SMSS octets that MUST include the highest outstanding
1806 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1807 * RecoveryPoint. HighRxt MUST NOT be updated.
1808 */
Florin Coras3eba7f12019-11-15 17:56:48 -08001809 hole = scoreboard_last_hole (sb);
1810 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
Florin Coras1f152cd2017-08-18 19:28:03 -07001811 max_bytes = clib_min (max_bytes, snd_space);
Florin Coras3eba7f12019-11-15 17:56:48 -08001812 offset = hole->end - tc->snd_una - max_bytes;
Florin Corasbe72ae62018-11-01 11:23:03 -07001813 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1814 max_bytes, &b);
Florin Coras24793e32018-05-09 11:34:25 -07001815 if (!n_written)
1816 goto done;
1817
Florin Coras3eba7f12019-11-15 17:56:48 -08001818 sb->rescue_rxt = tc->snd_congestion;
Florin Corasb2215d62017-08-01 16:56:58 -07001819 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001820 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001821 n_segs += 1;
Florin Coras93992a92017-05-24 18:03:56 -07001822 break;
1823 }
1824
Florin Coras1f152cd2017-08-18 19:28:03 -07001825 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1826 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1827 if (max_bytes == 0)
1828 break;
Florin Coras36ee9f12018-11-02 12:52:10 -07001829
Florin Coras93992a92017-05-24 18:03:56 -07001830 offset = sb->high_rxt - tc->snd_una;
Florin Corasbe72ae62018-11-01 11:23:03 -07001831 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1832 &b);
Florin Coras36ee9f12018-11-02 12:52:10 -07001833 ASSERT (n_written <= snd_space);
Florin Coras93992a92017-05-24 18:03:56 -07001834
1835 /* Nothing left to retransmit */
1836 if (n_written == 0)
Florin Corasb2215d62017-08-01 16:56:58 -07001837 break;
Florin Coras93992a92017-05-24 18:03:56 -07001838
Florin Corasb2215d62017-08-01 16:56:58 -07001839 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001840 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras36ee9f12018-11-02 12:52:10 -07001841
1842 sb->high_rxt += n_written;
Florin Coras81cb8e42019-10-22 19:44:45 -07001843 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1844
Florin Coras93992a92017-05-24 18:03:56 -07001845 snd_space -= n_written;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001846 n_segs += 1;
Florin Coras93992a92017-05-24 18:03:56 -07001847 }
1848
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001849 if (hole)
Florin Coras36ebcff2019-09-12 18:36:44 -07001850 tcp_program_retransmit (tc);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001851
Florin Coras24793e32018-05-09 11:34:25 -07001852done:
Florin Coras36ebcff2019-09-12 18:36:44 -07001853
Florin Coras11e9e352019-11-13 19:09:47 -08001854 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001855 return n_segs;
Florin Coras93992a92017-05-24 18:03:56 -07001856}
1857
1858/**
1859 * Fast retransmit without SACK info
1860 */
Florin Coras36ebcff2019-09-12 18:36:44 -07001861static int
1862tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1863 u32 burst_size)
Florin Coras93992a92017-05-24 18:03:56 -07001864{
Florin Corasbf1f8b72019-11-04 14:39:33 -08001865 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
Florin Corasc31dc312019-10-06 14:06:14 -07001866 u32 burst_bytes, sent_bytes;
Florin Corasbe72ae62018-11-01 11:23:03 -07001867 vlib_main_t *vm = wrk->vm;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001868 int snd_space, n_segs = 0;
Florin Corasc31dc312019-10-06 14:06:14 -07001869 u8 cc_limited = 0;
Florin Coras93992a92017-05-24 18:03:56 -07001870 vlib_buffer_t *b;
1871
Florin Corasbf1f8b72019-11-04 14:39:33 -08001872 ASSERT (tcp_in_cong_recovery (tc));
Florin Corasa436a422019-08-20 07:09:31 -07001873 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
Florin Coras6792ec02017-03-13 03:49:51 -07001874
Florin Corasa8e71c82019-10-22 19:01:39 -07001875 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
Florin Corasc31dc312019-10-06 14:06:14 -07001876 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1877 if (!burst_size)
1878 {
1879 tcp_program_retransmit (tc);
1880 return 0;
1881 }
1882
Florin Coras87a9bf82019-06-12 11:26:35 -07001883 snd_space = tcp_available_cc_snd_space (tc);
Florin Corasc31dc312019-10-06 14:06:14 -07001884 cc_limited = snd_space < burst_bytes;
Florin Coras87a9bf82019-06-12 11:26:35 -07001885
Florin Coras36ee9f12018-11-02 12:52:10 -07001886 if (!tcp_fastrecovery_first (tc))
1887 goto send_unsent;
1888
1889 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1890 * segment. */
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001891 while (snd_space > 0 && n_segs < burst_size)
Dave Barach68b0fb02017-02-28 15:15:56 -05001892 {
Florin Corasbf1f8b72019-11-04 14:39:33 -08001893 max_bytes = clib_min (tc->snd_mss,
1894 tc->snd_congestion - tc->snd_una - offset);
1895 if (!max_bytes)
1896 break;
1897 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1898 &b);
Dave Barach68b0fb02017-02-28 15:15:56 -05001899
1900 /* Nothing left to retransmit */
Florin Coras6792ec02017-03-13 03:49:51 -07001901 if (n_written == 0)
Florin Corasb2215d62017-08-01 16:56:58 -07001902 break;
Dave Barach68b0fb02017-02-28 15:15:56 -05001903
Florin Corasb2215d62017-08-01 16:56:58 -07001904 bi = vlib_get_buffer_index (vm, b);
Florin Corasbe72ae62018-11-01 11:23:03 -07001905 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
Florin Coras6792ec02017-03-13 03:49:51 -07001906 snd_space -= n_written;
Florin Coras36ee9f12018-11-02 12:52:10 -07001907 offset += n_written;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001908 n_segs += 1;
Dave Barach68b0fb02017-02-28 15:15:56 -05001909 }
1910
Florin Coras36ee9f12018-11-02 12:52:10 -07001911 if (n_segs == burst_size)
1912 goto done;
Florin Corasbf4d5ce2018-10-19 16:26:24 -07001913
Florin Coras36ee9f12018-11-02 12:52:10 -07001914send_unsent:
1915
1916 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
Florin Coras9ece3c02018-11-05 11:06:53 -08001917 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
Florin Coras36ee9f12018-11-02 12:52:10 -07001918 goto done;
1919
Florin Coras31c99552019-03-01 13:00:58 -08001920 max_deq = transport_max_tx_dequeue (&tc->connection);
Florin Coras47596832019-03-12 18:58:54 -07001921 max_deq -= tc->snd_nxt - tc->snd_una;
Florin Coras36ee9f12018-11-02 12:52:10 -07001922 if (max_deq)
1923 {
1924 snd_space = clib_min (max_deq, snd_space);
1925 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
Florin Coras36ebcff2019-09-12 18:36:44 -07001926 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
Florin Corasbf1f8b72019-11-04 14:39:33 -08001927 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
Florin Coras36ebcff2019-09-12 18:36:44 -07001928 tcp_program_retransmit (tc);
Florin Coras36ee9f12018-11-02 12:52:10 -07001929 n_segs += n_segs_now;
1930 }
1931
Florin Coras36ee9f12018-11-02 12:52:10 -07001932done:
1933 tcp_fastrecovery_first_off (tc);
Florin Coras93992a92017-05-24 18:03:56 -07001934
Florin Corasc31dc312019-10-06 14:06:14 -07001935 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1936 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1937 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1938
1939 return n_segs;
Dave Barach68b0fb02017-02-28 15:15:56 -05001940}
Florin Coras26dd6de2019-07-23 23:54:47 -07001941
1942static int
1943tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1944{
1945 int j, n_acks;
1946
1947 if (!tc->pending_dupacks)
1948 {
Florin Corascb711a42019-10-16 19:28:17 -07001949 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1950 || tc->state != TCP_STATE_ESTABLISHED)
1951 {
1952 tcp_send_ack (tc);
1953 return 1;
1954 }
1955 return 0;
Florin Coras26dd6de2019-07-23 23:54:47 -07001956 }
1957
1958 /* If we're supposed to send dupacks but have no ooo data
1959 * send only one ack */
1960 if (!vec_len (tc->snd_sacks))
1961 {
1962 tcp_send_ack (tc);
Florin Coras7fd59cc2020-03-12 15:50:57 +00001963 tc->dupacks_out += 1;
Florin Corascb711a42019-10-16 19:28:17 -07001964 tc->pending_dupacks = 0;
Florin Coras26dd6de2019-07-23 23:54:47 -07001965 return 1;
1966 }
1967
1968 /* Start with first sack block */
1969 tc->snd_sack_pos = 0;
1970
1971 /* Generate enough dupacks to cover all sack blocks. Do not generate
1972 * more sacks than the number of packets received. But do generate at
1973 * least 3, i.e., the number needed to signal congestion, if needed. */
1974 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1975 n_acks = clib_min (n_acks, tc->pending_dupacks);
1976 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1977 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1978 tcp_send_ack (tc);
1979
1980 if (n_acks < max_burst_size)
1981 {
1982 tc->pending_dupacks = 0;
1983 tc->snd_sack_pos = 0;
Florin Corasedfe0ee2019-07-29 18:13:25 -07001984 tc->dupacks_out += n_acks;
Florin Coras26dd6de2019-07-23 23:54:47 -07001985 return n_acks;
1986 }
1987 else
1988 {
1989 TCP_DBG ("constrained by burst size");
1990 tc->pending_dupacks = n_acks - max_burst_size;
Florin Corasedfe0ee2019-07-29 18:13:25 -07001991 tc->dupacks_out += max_burst_size;
Florin Coras26dd6de2019-07-23 23:54:47 -07001992 tcp_program_dupack (tc);
1993 return max_burst_size;
1994 }
1995}
1996
1997static int
Florin Coras36ebcff2019-09-12 18:36:44 -07001998tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
Florin Coras26dd6de2019-07-23 23:54:47 -07001999{
Florin Coras26dd6de2019-07-23 23:54:47 -07002000 tcp_worker_ctx_t *wrk;
Florin Corasc31dc312019-10-06 14:06:14 -07002001 u32 n_segs;
Florin Coras26dd6de2019-07-23 23:54:47 -07002002
Florin Corasfd4c3fe2019-11-07 12:33:12 -08002003 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2004 return 0;
2005
Florin Coras26dd6de2019-07-23 23:54:47 -07002006 wrk = tcp_get_worker (tc->c_thread_index);
Florin Coras26dd6de2019-07-23 23:54:47 -07002007
Florin Corasc31dc312019-10-06 14:06:14 -07002008 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2009 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2010 else
2011 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2012
Florin Coras26dd6de2019-07-23 23:54:47 -07002013 return n_segs;
2014}
2015
2016int
Florin Coras9f86d222020-03-23 15:34:22 +00002017tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
Florin Coras26dd6de2019-07-23 23:54:47 -07002018{
2019 tcp_connection_t *tc = (tcp_connection_t *) conn;
2020 u32 n_segs = 0;
2021
Florin Coras36ebcff2019-09-12 18:36:44 -07002022 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
Florin Coras26dd6de2019-07-23 23:54:47 -07002023 {
Florin Coras36ebcff2019-09-12 18:36:44 -07002024 tc->flags &= ~TCP_CONN_RXT_PENDING;
Florin Coras9f86d222020-03-23 15:34:22 +00002025 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
Florin Coras26dd6de2019-07-23 23:54:47 -07002026 }
2027
2028 if (!(tc->flags & TCP_CONN_SNDACK))
2029 return n_segs;
2030
2031 tc->flags &= ~TCP_CONN_SNDACK;
2032
2033 /* We have retransmitted packets and no dupack */
2034 if (n_segs && !tc->pending_dupacks)
2035 return n_segs;
2036
Florin Coras9f86d222020-03-23 15:34:22 +00002037 if (sp->max_burst_size <= n_segs)
Florin Coras26dd6de2019-07-23 23:54:47 -07002038 {
2039 tcp_program_ack (tc);
Florin Coras9f86d222020-03-23 15:34:22 +00002040 return n_segs;
Florin Coras26dd6de2019-07-23 23:54:47 -07002041 }
2042
Florin Coras9f86d222020-03-23 15:34:22 +00002043 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
Florin Coras26dd6de2019-07-23 23:54:47 -07002044
2045 return n_segs;
2046}
Filip Tehlare275bed2019-03-06 00:06:56 -08002047#endif /* CLIB_MARCH_VARIANT */
Dave Barach68b0fb02017-02-28 15:15:56 -05002048
Florin Corasf9d05682018-04-26 08:26:52 -07002049static void
2050tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
Florin Coras8b20bf52018-06-14 14:55:50 -07002051 u16 * next0, u32 * error0)
Florin Corasf9d05682018-04-26 08:26:52 -07002052{
2053 ip_adjacency_t *adj;
2054 adj_index_t ai;
2055
Florin Coras1c8ff632018-05-17 13:28:34 -07002056 /* Not thread safe but as long as the connection exists the adj should
2057 * not be removed */
Florin Corasf9d05682018-04-26 08:26:52 -07002058 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2059 tc0->sw_if_index);
2060 if (ai == ADJ_INDEX_INVALID)
2061 {
Florin Corasf9d05682018-04-26 08:26:52 -07002062 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2063 *next0 = TCP_OUTPUT_NEXT_DROP;
2064 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2065 return;
2066 }
2067
2068 adj = adj_get (ai);
Florin Coras1c8ff632018-05-17 13:28:34 -07002069 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
Florin Corasf9d05682018-04-26 08:26:52 -07002070 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2071 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2072 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
Florin Coras1c8ff632018-05-17 13:28:34 -07002073 else
2074 {
2075 *next0 = TCP_OUTPUT_NEXT_DROP;
2076 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2077 }
2078 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
Florin Corasf9d05682018-04-26 08:26:52 -07002079}
2080
Florin Coras8b20bf52018-06-14 14:55:50 -07002081static void
2082tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2083 u32 * to_next, u32 n_bufs)
Dave Barach68b0fb02017-02-28 15:15:56 -05002084{
Florin Coras8b20bf52018-06-14 14:55:50 -07002085 tcp_connection_t *tc;
2086 tcp_tx_trace_t *t;
2087 vlib_buffer_t *b;
2088 tcp_header_t *th;
2089 int i;
Dave Barach68b0fb02017-02-28 15:15:56 -05002090
Florin Coras30928f82020-01-27 19:21:28 -08002091 for (i = 0; i < n_bufs; i++)
Dave Barach68b0fb02017-02-28 15:15:56 -05002092 {
Florin Coras8b20bf52018-06-14 14:55:50 -07002093 b = vlib_get_buffer (vm, to_next[i]);
Florin Coras30928f82020-01-27 19:21:28 -08002094 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2095 continue;
Florin Coras8b20bf52018-06-14 14:55:50 -07002096 th = vlib_buffer_get_current (b);
2097 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2098 vm->thread_index);
2099 t = vlib_add_trace (vm, node, b, sizeof (*t));
Dave Barach178cf492018-11-13 16:34:13 -05002100 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2101 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
Florin Coras8b20bf52018-06-14 14:55:50 -07002102 }
2103}
Dave Barach68b0fb02017-02-28 15:15:56 -05002104
Florin Coras0dbd5172018-06-25 16:19:34 -07002105always_inline void
Florin Coras8b20bf52018-06-14 14:55:50 -07002106tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2107 tcp_connection_t * tc0, u8 is_ip4)
2108{
Florin Corasf4ce6ba2019-11-20 18:34:58 -08002109 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2110 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2111 b0->current_length);
Srikanth A02833ff2019-10-02 17:48:58 -07002112
Florin Coras8b20bf52018-06-14 14:55:50 -07002113 if (is_ip4)
Florin Corasf4ce6ba2019-11-20 18:34:58 -08002114 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2115 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
Florin Coras8b20bf52018-06-14 14:55:50 -07002116 else
Florin Corasf4ce6ba2019-11-20 18:34:58 -08002117 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2118 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
Florin Coras8b20bf52018-06-14 14:55:50 -07002119}
Dave Barach68b0fb02017-02-28 15:15:56 -05002120
Florin Coras0dbd5172018-06-25 16:19:34 -07002121always_inline void
Simon Zhang1146ff42019-09-02 22:54:00 +08002122tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2123{
Florin Corasbbcfaac2019-10-10 13:52:04 -07002124 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
Simon Zhang1146ff42019-09-02 22:54:00 +08002125 return;
Florin Corasbbcfaac2019-10-10 13:52:04 -07002126
Simon Zhang8a047ed2019-09-24 21:16:56 +08002127 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
Simon Zhang1146ff42019-09-02 22:54:00 +08002128
Simon Zhang8a047ed2019-09-24 21:16:56 +08002129 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2130 data_len += b->total_length_not_including_first_buffer;
2131
2132 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2133 return;
2134 else
Simon Zhang1146ff42019-09-02 22:54:00 +08002135 {
2136 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2137 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2138 b->flags |= VNET_BUFFER_F_GSO;
2139 vnet_buffer2 (b)->gso_l4_hdr_sz =
2140 sizeof (tcp_header_t) + tc->snd_opts_len;
2141 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2142 }
2143}
2144
2145always_inline void
Florin Coras8b20bf52018-06-14 14:55:50 -07002146tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
Florin Corasdf36f492019-08-18 18:09:28 -07002147 vlib_node_runtime_t * error_node, u16 * next0,
2148 u8 is_ip4)
Florin Coras8b20bf52018-06-14 14:55:50 -07002149{
Florin Coras540a8da2019-06-18 08:55:14 -07002150 /* If next_index is not drop use it */
Florin Coras07beade2019-06-20 12:18:31 -07002151 if (tc0->next_node_index)
2152 {
2153 *next0 = tc0->next_node_index;
2154 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2155 }
Florin Coras78dae002019-08-30 10:00:30 -07002156 else
2157 {
2158 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2159 }
Florin Coras540a8da2019-06-18 08:55:14 -07002160
Florin Coras8b20bf52018-06-14 14:55:50 -07002161 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2162 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2163
2164 if (!is_ip4)
2165 {
Florin Corasdf36f492019-08-18 18:09:28 -07002166 u32 error0 = 0;
2167
Florin Coras8b20bf52018-06-14 14:55:50 -07002168 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
Florin Corasdf36f492019-08-18 18:09:28 -07002169 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2170
2171 if (PREDICT_FALSE (error0))
2172 {
2173 b0->error = error_node->errors[error0];
2174 return;
2175 }
Florin Coras8b20bf52018-06-14 14:55:50 -07002176 }
2177
Florin Corasedfe0ee2019-07-29 18:13:25 -07002178 tc0->segs_out += 1;
Florin Coras8b20bf52018-06-14 14:55:50 -07002179}
2180
2181always_inline uword
2182tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2183 vlib_frame_t * frame, int is_ip4)
2184{
2185 u32 n_left_from, *from, thread_index = vm->thread_index;
2186 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2187 u16 nexts[VLIB_FRAME_SIZE], *next;
2188
2189 from = vlib_frame_vector_args (frame);
2190 n_left_from = frame->n_vectors;
Florin Coras8f10b902021-04-02 18:32:00 -07002191 tcp_update_time_now (tcp_get_worker (thread_index));
Florin Coras8b20bf52018-06-14 14:55:50 -07002192
2193 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2194 tcp46_output_trace_frame (vm, node, from, n_left_from);
2195
2196 vlib_get_buffers (vm, from, bufs, n_left_from);
2197 b = bufs;
2198 next = nexts;
2199
2200 while (n_left_from >= 4)
2201 {
Florin Coras8b20bf52018-06-14 14:55:50 -07002202 tcp_connection_t *tc0, *tc1;
2203
2204 {
2205 vlib_prefetch_buffer_header (b[2], STORE);
2206 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2207
2208 vlib_prefetch_buffer_header (b[3], STORE);
2209 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2210 }
2211
Florin Coras8b20bf52018-06-14 14:55:50 -07002212 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2213 thread_index);
2214 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2215 thread_index);
2216
Florin Coras78dae002019-08-30 10:00:30 -07002217 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2218 {
2219 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2220 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
Florin Coras8b20bf52018-06-14 14:55:50 -07002221
Simon Zhang1146ff42019-09-02 22:54:00 +08002222 tcp_check_if_gso (tc0, b[0]);
2223 tcp_check_if_gso (tc1, b[1]);
2224
Florin Coras573f44c2020-04-09 21:23:01 +00002225 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2226 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
Florin Coras78dae002019-08-30 10:00:30 -07002227 }
2228 else
2229 {
2230 if (tc0 != 0)
2231 {
2232 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002233 tcp_check_if_gso (tc0, b[0]);
Florin Coras573f44c2020-04-09 21:23:01 +00002234 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
Florin Coras78dae002019-08-30 10:00:30 -07002235 }
2236 else
2237 {
Florin Coras573f44c2020-04-09 21:23:01 +00002238 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
Florin Coras78dae002019-08-30 10:00:30 -07002239 next[0] = TCP_OUTPUT_NEXT_DROP;
2240 }
2241 if (tc1 != 0)
2242 {
2243 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002244 tcp_check_if_gso (tc1, b[1]);
Florin Coras573f44c2020-04-09 21:23:01 +00002245 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
Florin Coras78dae002019-08-30 10:00:30 -07002246 }
2247 else
2248 {
Florin Coras573f44c2020-04-09 21:23:01 +00002249 b[1]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
Florin Coras78dae002019-08-30 10:00:30 -07002250 next[1] = TCP_OUTPUT_NEXT_DROP;
2251 }
2252 }
Florin Coras8b20bf52018-06-14 14:55:50 -07002253
2254 b += 2;
2255 next += 2;
2256 n_left_from -= 2;
2257 }
2258 while (n_left_from > 0)
2259 {
Florin Coras8b20bf52018-06-14 14:55:50 -07002260 tcp_connection_t *tc0;
2261
2262 if (n_left_from > 1)
2263 {
Florin Coras91ca4622018-06-30 11:27:59 -07002264 vlib_prefetch_buffer_header (b[1], STORE);
2265 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
Florin Coras8b20bf52018-06-14 14:55:50 -07002266 }
2267
Florin Coras8b20bf52018-06-14 14:55:50 -07002268 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2269 thread_index);
2270
Florin Coras78dae002019-08-30 10:00:30 -07002271 if (PREDICT_TRUE (tc0 != 0))
2272 {
2273 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
Simon Zhang1146ff42019-09-02 22:54:00 +08002274 tcp_check_if_gso (tc0, b[0]);
Florin Coras573f44c2020-04-09 21:23:01 +00002275 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
Florin Coras78dae002019-08-30 10:00:30 -07002276 }
2277 else
2278 {
Florin Coras573f44c2020-04-09 21:23:01 +00002279 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
Florin Coras78dae002019-08-30 10:00:30 -07002280 next[0] = TCP_OUTPUT_NEXT_DROP;
2281 }
Florin Coras8b20bf52018-06-14 14:55:50 -07002282
2283 b += 1;
2284 next += 1;
2285 n_left_from -= 1;
2286 }
2287
2288 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
Florin Corasdf36f492019-08-18 18:09:28 -07002289 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2290 TCP_ERROR_PKTS_SENT, frame->n_vectors);
Florin Coras8b20bf52018-06-14 14:55:50 -07002291 return frame->n_vectors;
Dave Barach68b0fb02017-02-28 15:15:56 -05002292}
2293
Filip Tehlare275bed2019-03-06 00:06:56 -08002294VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2295 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002296{
2297 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2298}
2299
Filip Tehlare275bed2019-03-06 00:06:56 -08002300VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2301 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002302{
2303 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2304}
2305
Florin Corase69f4952017-03-07 10:06:24 -08002306/* *INDENT-OFF* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002307VLIB_REGISTER_NODE (tcp4_output_node) =
2308{
Dave Barachf970d2f2018-11-26 18:34:33 -05002309 .name = "tcp4-output",
2310 /* Takes a vector of packets. */
2311 .vector_size = sizeof (u32),
2312 .n_errors = TCP_N_ERROR,
Dave Barach7fff3d22018-11-27 16:52:59 -05002313 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
Dave Barachf970d2f2018-11-26 18:34:33 -05002314 .error_strings = tcp_error_strings,
2315 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2316 .next_nodes = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002317#define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2318 foreach_tcp4_output_next
2319#undef _
Dave Barachf970d2f2018-11-26 18:34:33 -05002320 },
2321 .format_buffer = format_tcp_header,
2322 .format_trace = format_tcp_tx_trace,
Florin Corase69f4952017-03-07 10:06:24 -08002323};
2324/* *INDENT-ON* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002325
Florin Corase69f4952017-03-07 10:06:24 -08002326/* *INDENT-OFF* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002327VLIB_REGISTER_NODE (tcp6_output_node) =
2328{
Florin Corase69f4952017-03-07 10:06:24 -08002329 .name = "tcp6-output",
Dave Barach68b0fb02017-02-28 15:15:56 -05002330 /* Takes a vector of packets. */
Florin Corase69f4952017-03-07 10:06:24 -08002331 .vector_size = sizeof (u32),
2332 .n_errors = TCP_N_ERROR,
Dave Barach7fff3d22018-11-27 16:52:59 -05002333 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
Florin Corase69f4952017-03-07 10:06:24 -08002334 .error_strings = tcp_error_strings,
2335 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2336 .next_nodes = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002337#define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2338 foreach_tcp6_output_next
2339#undef _
Florin Corase69f4952017-03-07 10:06:24 -08002340 },
2341 .format_buffer = format_tcp_header,
2342 .format_trace = format_tcp_tx_trace,
2343};
2344/* *INDENT-ON* */
Dave Barach68b0fb02017-02-28 15:15:56 -05002345
Dave Barach68b0fb02017-02-28 15:15:56 -05002346typedef enum _tcp_reset_next
2347{
2348 TCP_RESET_NEXT_DROP,
2349 TCP_RESET_NEXT_IP_LOOKUP,
2350 TCP_RESET_N_NEXT
2351} tcp_reset_next_t;
2352
2353#define foreach_tcp4_reset_next \
2354 _(DROP, "error-drop") \
2355 _(IP_LOOKUP, "ip4-lookup")
2356
2357#define foreach_tcp6_reset_next \
2358 _(DROP, "error-drop") \
2359 _(IP_LOOKUP, "ip6-lookup")
2360
2361static uword
2362tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2363 vlib_frame_t * from_frame, u8 is_ip4)
2364{
Florin Coras360336f2020-02-13 18:46:18 +00002365 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
Dave Barach68b0fb02017-02-28 15:15:56 -05002366 u32 n_left_from, next_index, *from, *to_next;
Dave Barach68b0fb02017-02-28 15:15:56 -05002367
2368 from = vlib_frame_vector_args (from_frame);
2369 n_left_from = from_frame->n_vectors;
2370
2371 next_index = node->cached_next_index;
2372
2373 while (n_left_from > 0)
2374 {
2375 u32 n_left_to_next;
2376
2377 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2378
2379 while (n_left_from > 0 && n_left_to_next > 0)
2380 {
Dave Barach68b0fb02017-02-28 15:15:56 -05002381 vlib_buffer_t *b0;
Clement Durand6cf260c2017-04-13 13:27:04 +02002382 tcp_tx_trace_t *t0;
2383 tcp_header_t *th0;
Florin Coras360336f2020-02-13 18:46:18 +00002384 u32 bi0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002385
2386 bi0 = from[0];
2387 to_next[0] = bi0;
2388 from += 1;
2389 to_next += 1;
2390 n_left_from -= 1;
2391 n_left_to_next -= 1;
2392
2393 b0 = vlib_get_buffer (vm, bi0);
Florin Coras360336f2020-02-13 18:46:18 +00002394 tcp_make_reset_in_place (vm, b0, is_ip4);
Dave Barach68b0fb02017-02-28 15:15:56 -05002395
2396 /* Prepare to send to IP lookup */
Florin Corasf988e692017-11-27 04:34:14 -05002397 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
Dave Barach68b0fb02017-02-28 15:15:56 -05002398
Florin Corase69f4952017-03-07 10:06:24 -08002399 b0->error = node->errors[error0];
Damjan Marion213b5aa2017-07-13 21:19:27 +02002400 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
Dave Barach68b0fb02017-02-28 15:15:56 -05002401 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2402 {
Clement Durand6cf260c2017-04-13 13:27:04 +02002403 th0 = vlib_buffer_get_current (b0);
2404 if (is_ip4)
2405 th0 = ip4_next_header ((ip4_header_t *) th0);
2406 else
2407 th0 = ip6_next_header ((ip6_header_t *) th0);
Clement Durand6cf260c2017-04-13 13:27:04 +02002408 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
Dave Barach178cf492018-11-13 16:34:13 -05002409 clib_memcpy_fast (&t0->tcp_header, th0,
2410 sizeof (t0->tcp_header));
Dave Barach68b0fb02017-02-28 15:15:56 -05002411 }
2412
2413 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2414 n_left_to_next, bi0, next0);
2415 }
2416 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2417 }
2418 return from_frame->n_vectors;
2419}
2420
Filip Tehlare275bed2019-03-06 00:06:56 -08002421VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2422 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002423{
2424 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2425}
2426
Filip Tehlare275bed2019-03-06 00:06:56 -08002427VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2428 vlib_frame_t * from_frame)
Dave Barach68b0fb02017-02-28 15:15:56 -05002429{
2430 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2431}
2432
2433/* *INDENT-OFF* */
2434VLIB_REGISTER_NODE (tcp4_reset_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002435 .name = "tcp4-reset",
2436 .vector_size = sizeof (u32),
2437 .n_errors = TCP_N_ERROR,
2438 .error_strings = tcp_error_strings,
2439 .n_next_nodes = TCP_RESET_N_NEXT,
2440 .next_nodes = {
2441#define _(s,n) [TCP_RESET_NEXT_##s] = n,
2442 foreach_tcp4_reset_next
2443#undef _
2444 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002445 .format_trace = format_tcp_tx_trace,
Dave Barach68b0fb02017-02-28 15:15:56 -05002446};
2447/* *INDENT-ON* */
2448
2449/* *INDENT-OFF* */
2450VLIB_REGISTER_NODE (tcp6_reset_node) = {
Dave Barach68b0fb02017-02-28 15:15:56 -05002451 .name = "tcp6-reset",
2452 .vector_size = sizeof (u32),
2453 .n_errors = TCP_N_ERROR,
2454 .error_strings = tcp_error_strings,
2455 .n_next_nodes = TCP_RESET_N_NEXT,
2456 .next_nodes = {
2457#define _(s,n) [TCP_RESET_NEXT_##s] = n,
2458 foreach_tcp6_reset_next
2459#undef _
2460 },
Clement Durand6cf260c2017-04-13 13:27:04 +02002461 .format_trace = format_tcp_tx_trace,
Dave Barach68b0fb02017-02-28 15:15:56 -05002462};
2463/* *INDENT-ON* */
2464
Dave Barach68b0fb02017-02-28 15:15:56 -05002465/*
2466 * fd.io coding-style-patch-verification: ON
2467 *
2468 * Local Variables:
2469 * eval: (c-set-style "gnu")
2470 * End:
2471 */